JP4631033B2 - Method for manufacturing photoelectric conversion device - Google Patents

Description

  The present invention relates to a method for manufacturing a photoelectric conversion device in which a spherical photoelectric conversion element is mounted.

  As a clean energy source, a photoelectric conversion device has attracted attention. A typical photoelectric conversion device uses an element made of a crystalline silicon semiconductor wafer and uses a semiconductor layer made of amorphous silicon. In the former, the steps from the production of a single crystal ingot and the production of a semiconductor wafer from the single crystal ingot are complicated, and the utilization rate of expensive silicon raw materials is low due to crystal cutting waste and the like, resulting in high costs. The latter has a problem in that the amorphous structure in which hydrogen is bonded to the dangling bonds of silicon is likely to undergo structural change due to the release of hydrogen by light irradiation, so that the photoelectric conversion efficiency is gradually lowered by light irradiation.

  As a photoelectric conversion device that does not have the above-described characteristic deterioration, is inexpensive, and can be expected to have high output, a device using a spherical photoelectric conversion element in which an n-type semiconductor layer is formed on the surface of a spherical p-type semiconductor has been studied. Yes. This photoelectric conversion device uses a small spherical element having a diameter of about 1 mm, thereby reducing the average thickness of the entire photoelectric conversion unit and reducing the amount of raw material Si used.

  As this type of photoelectric conversion device, there is known a device in which a spherical photoelectric conversion element having a diameter of about 1 mm is attached to each concave portion of a support having a large number of concave portions, and the inner surface of the concave portion serves as a reflecting mirror (Patent Document). 1 and 2). According to such a configuration, it is possible to reduce the amount of element material, particularly expensive Si, and to irradiate the element with 4 to 6 times the light directly irradiated to the element by the action of the reflecting mirror. It has the advantage that light can be used effectively.

A typical structure of this type of photoelectric conversion device is shown in Patent Document 2. The photoelectric conversion element includes a spherical first semiconductor and a second semiconductor layer covering the surface thereof, and the second semiconductor layer has an opening that exposes a part of the first semiconductor. The support having a plurality of recesses to which the photoelectric conversion elements are individually attached has a hole for fitting the photoelectric conversion element to the bottom of the recesses so that the exposed surface of the first semiconductor faces the back side of the support. Yes. The support includes a second conductor layer that forms the inner surface of the recess and is electrically connected to the second semiconductor layer, and an electrical insulating layer provided on the back surface of the second conductor layer. The first conductor layer connected to the exposed portion of the first semiconductor through the hole of the support is attached to the back surface of the support.
JP 2002-164554 A JP 2004-063564 A

  In manufacturing the conventional photoelectric conversion device, after the electrodes of the photoelectric conversion element are accurately positioned in the holes of the support (second conductor layer), the second semiconductor layer is electrically connected to the support. Then, from the opposite side of the support, the first conductor layer on which the protrusion is formed at a position corresponding to the hole of the support and the electrode of the photoelectric conversion element are electrically connected.

  In the process of manufacturing a photoelectric conversion device in which a spherical element is mounted on a support, it is necessary to mount an extremely large number of spherical elements in the recesses of the support at high speed. For this reason, a short circuit may occur between the support and the first semiconductor electrode. If there is even one such element, the first conductor layer and the second conductor layer are short-circuited, and there is a situation in which power cannot be taken out from the photoelectric conversion device. It was almost impossible to get rid of. Furthermore, once the photoelectric conversion device has failed, it has been difficult to disassemble and regenerate. When such a situation occurs, all of the man-hours and materials required to complete the photoelectric conversion device are lost, and productivity is significantly impaired.

    The present invention solves the above-described conventional problems, and can produce output even when a short circuit occurs between the electrode of the first semiconductor and the support due to misalignment when the element is mounted, etc. It is an object of the present invention to provide a method for manufacturing a photoelectric conversion device suitable for the above.

In order to achieve the above object, the first method for producing a photoelectric conversion device of the present invention is as follows.
(1) It comprises a spherical first semiconductor and a second semiconductor layer covering the surface thereof, the second semiconductor layer has an opening for exposing a part of the first semiconductor, and the first semiconductor is exposed. A plurality of substantially spherical photoelectric conversion elements each having an electrode formed thereon, and a plurality of adjacent recesses, and the recess is formed of a conductive support having a hole smaller than the photoelectric conversion element at the bottom;
The photoelectric conversion element is mounted in each recess of the support so that the exposed portion of the first semiconductor faces the back side of the support from the hole, and the second semiconductor layer of the photoelectric conversion element is supported by the support Preparing a structure electrically connected to the body,
(2) A step of inspecting the presence or absence of a short circuit between the electrode of the first semiconductor of the photoelectric conversion element mounted on the support and the support,
(3) forming an electrical insulating layer on the back side of the support;
(4) In the step (2), a hole is formed in the electrical insulating layer to expose the electrode in the hole for the photoelectric conversion element that is not short-circuited between the electrode of the first semiconductor and the support. And (5) a step of electrically connecting the electrodes of the first semiconductors of the plurality of photoelectric conversion elements mounted on the support to each other.

  In the first method for manufacturing a photoelectric conversion device according to the present invention, in the step (5), the conductive paste is applied to the surface of the electrode exposed in the hole by filling the hole in the electrical insulating layer with the conductive paste. In addition, it may include a step of applying a conductive paste on the electrical insulating layer so as to connect the conductive paste and solidifying by heating. Alternatively, in the step (5), the conductive paste is applied to the surface of the electrode exposed in the hole by filling the hole in the electrical insulating layer with the conductive paste, and then the conductive metal sheet is applied to the electrical insulating layer. And a step of electrically solidifying the conductive paste and electrically connecting the conductive paste and the conductive metal sheet.

Next, the manufacturing method of the 2nd photoelectric conversion apparatus of this invention is as follows.
(1) It comprises a spherical first semiconductor and a second semiconductor layer covering the surface thereof, the second semiconductor layer has an opening for exposing a part of the first semiconductor, and the first semiconductor is exposed. A plurality of substantially spherical photoelectric conversion elements each having an electrode formed thereon, and a plurality of adjacent recesses, and the recess is formed of a conductive support having a hole smaller than the photoelectric conversion element at the bottom;
The photoelectric conversion element is mounted in each recess of the support so that the exposed portion of the first semiconductor faces the back side of the support from the hole, and the second semiconductor layer of the photoelectric conversion element is supported by the support Preparing a structure electrically connected to the body,
(2) A step of inspecting the presence or absence of a short circuit between the electrode of the first semiconductor of the photoelectric conversion element mounted on the support and the support,
(3) The process of joining the electrically insulating layer which isolates a conductive metal sheet and the said conductive metal sheet, and the said support body to the back surface side of the said support body,
(4) In the step (2), for the photoelectric conversion element that is not short-circuited between the electrode of the first semiconductor and the support, the photoelectric conversion is performed by opening a hole in the electrical insulating layer and the conductive metal sheet. A step of exposing the electrode of the element in the hole; and (5) filling the hole of the electrical insulating layer and the conductive metal sheet with a conductive paste and applying the conductive paste to the surface of the electrode exposed in the hole. And a step of electrically connecting each electrode of the first semiconductor of the plurality of photoelectric conversion elements and the conductive metal sheet.

  In the second method for manufacturing a photoelectric conversion device according to the present invention, the step (3) includes a step of integrating a composite sheet in which an electrical insulating layer is joined to one side of a conductive metal sheet on the back side of the support. The step of joining the electrical insulating layer to the support may be included.

  Moreover, in the manufacturing method of the 1st or 2nd photoelectric conversion apparatus of this invention, in the said process (1), the said photoelectric conversion element through the electroconductive adhesive apply | coated to the peripheral part of the hole of the recessed part of the said support body Is fixed, and the second semiconductor layer and the support are preferably electrically connected.

  In the first or second method for manufacturing a photoelectric conversion device according to the present invention, for each photoelectric conversion element mounted on the support, data on the inspection result in the step (2) and the position of the recess of the support In the step (4), the data stored in the memory is read out, and the electrical insulating layer or the electrical insulating layer and the conductive sheet are opened based on the data. It is preferable to determine whether or not. Similarly, in the step (2), a stylus is brought into contact with the electrode of the photoelectric conversion element from the back side of the support, and a current flowing between the stylus and the support is measured to determine whether or not there is a short circuit. It is preferable to inspect.

  In the first or second method for manufacturing a photoelectric conversion device of the present invention, instead of the step (2), the mounting state of the photoelectric conversion element mounted on the support is photographed using a camera, The presence or absence of contact between the first semiconductor electrode and the peripheral edge of the support or the conductive adhesive connected to the peripheral edge may be inspected.

Next, the third method for producing a photoelectric conversion device of the present invention is as follows.
(1) It comprises a spherical first semiconductor and a second semiconductor layer covering the surface thereof, the second semiconductor layer has an opening for exposing a part of the first semiconductor, and the first semiconductor is exposed. A plurality of substantially spherical photoelectric conversion elements each having an electrode formed thereon, and a plurality of adjacent recesses, and the recess is formed of a conductive support having a hole smaller than the photoelectric conversion element at the bottom;
The photoelectric conversion element is mounted in each recess of the support so that the exposed portion of the first semiconductor faces the back side of the support from the hole, and the second semiconductor layer of the photoelectric conversion element is supported by the support Preparing a structure electrically connected to the body,
(2) forming an electrical insulating layer on the back side of the support;
(3) A step of opening a hole in the electrical insulating layer to expose a first semiconductor electrode of the photoelectric conversion element in the hole;
(4) A step of filling the hole of the electrical insulating layer with a conductive paste and applying the conductive paste to the surface of the electrode exposed in the hole;
(5) A step of inspecting for the presence or absence of a short circuit between the conductive paste filled in the holes of the electrical insulating layer and the support,
(6) In the step (5), the conductive paste filled in the hole of the electrical insulating layer is made of an insulator with respect to the photoelectric conversion element short-circuited between the conductive paste and the support. A step of covering, and (7) a step of electrically connecting each electrode of the plurality of photoelectric conversion elements through a conductive paste filled in the holes of the electrical insulating layer.

  In the third method for manufacturing a photoelectric conversion device of the present invention, the step (7) applies a conductive paste on the electrical insulating layer so as to connect the conductive paste filled in the holes of the electrical insulating layer. Or a step of solidifying by heating. Alternatively, in the step (7), after a conductive metal sheet is bonded to the electrical insulating layer, the conductive paste is heated and solidified to electrically connect the conductive paste and the conductive metal sheet. It may be included.

  In the third method for producing a photoelectric conversion device of the present invention, for each photoelectric conversion element mounted on the support, data relating to the inspection result in the step (5) and data relating to the position of the concave portion of the support are obtained. In the step (6), the data stored in the memory is read out, and based on this data, it is determined whether or not the conductive paste filled in the holes of the electrical insulating layer is covered with an insulator. It is preferable to do. Similarly, in the step (5), the stylus is brought into contact with the conductive paste filled in the hole of the electrical insulating layer from the back side of the support, and the current flowing between the stylus and the support is changed. It is preferable to inspect the presence or absence of a short circuit by measuring.

Next, the fourth method for producing a photoelectric conversion device of the present invention is as follows.
(1) A plurality of substantially spherical photoelectric conversion elements comprising a spherical first semiconductor and a second semiconductor layer covering the surface thereof, and a plurality of adjacent recesses, and a hole smaller than the photoelectric conversion element at the bottom. Consists of a conductive support,
Preparing a structure in which the photoelectric conversion element is mounted in each recess of the support and the second semiconductor layer of the photoelectric conversion element is electrically connected to the support;
(2) removing the second semiconductor layer of the photoelectric conversion element exposed to the back side from the hole of the support to expose a part of the first semiconductor;
(3) forming an electrical insulating layer on the back side of the support;
(4) A step of opening a hole in the electrical insulating layer to expose a part of the first semiconductor of the photoelectric conversion element in the hole;
(5) Filling the hole of the electrical insulating layer with a conductive paste and applying the conductive paste to the surface of the first semiconductor exposed in the hole, followed by heat treatment to form an electrode;
(6) A step of inspecting the presence or absence of a short circuit between the electrode formed on the first semiconductor and the support,
(7) The step of covering the electrode with an insulator for the photoelectric conversion element short-circuited between the electrode and the support in the step (6), and (8) The electrode in the step (7). The method includes a step of electrically connecting each electrode of the first semiconductor of the plurality of photoelectric conversion elements except for the photoelectric conversion element covered with an insulator.

Furthermore, the fifth method for producing a photoelectric conversion device of the present invention is as follows.
(1) A plurality of substantially spherical photoelectric conversion elements comprising a spherical first semiconductor and a second semiconductor layer covering the surface thereof, and a plurality of adjacent recesses, and a hole smaller than the photoelectric conversion element at the bottom. Consists of a conductive support,
Preparing a structure in which the photoelectric conversion element is mounted in each recess of the support and the second semiconductor layer of the photoelectric conversion element is electrically connected to the support;
(2) forming an electrical insulating layer on the back side of the support;
(3) A step of opening a hole in the electrical insulating layer to expose a part of the second semiconductor layer of the photoelectric conversion element in the hole;
(4) removing the second semiconductor layer of the photoelectric conversion element exposed in the hole of the electrical insulating layer to expose a part of the first semiconductor;
(5) A step of applying a conductive paste to the surface of the first semiconductor exposed in the hole of the electrical insulating layer, and then performing a heat treatment to form an electrode;
(6) A step of inspecting the presence or absence of a short circuit between the electrode formed on the first semiconductor and the support,
(7) The step of covering the electrode with an insulator with respect to the photoelectric conversion element short-circuited between the electrode of the first semiconductor and the support in the step (6), and (8) the step (7 The step of electrically connecting the respective electrodes of the first semiconductors of the plurality of photoelectric conversion elements, except for the photoelectric conversion element in which the electrodes are covered with an insulator.

  In the fourth or fifth method for manufacturing a photoelectric conversion device of the present invention, the step (8) applies a conductive paste on the electrical insulating layer so as to connect the electrodes of the first semiconductor of the photoelectric conversion element. Or a step of solidifying by heating. Alternatively, the step (8) includes a step of electrically connecting the first semiconductor electrode of the photoelectric conversion element and the conductive metal sheet after joining the conductive metal sheet to the electrical insulating layer. There may be.

  In addition, in the fourth or fifth method for manufacturing a photoelectric conversion device of the present invention, for each photoelectric conversion element mounted on the support, data on the inspection result in the step (6) and the position of the recess of the support In the step (7), the data stored in the memory is read out, and based on this data, it is determined whether or not to cover the electrode formed on the first semiconductor with an insulator. It is preferable. Similarly, in the step (6), a stylus is brought into contact with an electrode formed on the first semiconductor from the back side of the support, and a current flowing between the stylus and the support is measured. It is preferable to inspect for the presence of a short circuit.

According to the present invention, in the process of mounting a large number of spherical photoelectric conversion elements on a support to complete a photoelectric conversion device, the first conductor layer and the second conductive layer, such as an element in which the electrode and the support are short-circuited, are obtained. By extracting an element that leads to a short circuit with the conductor layer by inspection, and excluding such an element and electrically connecting the electrode to the first conductor layer, the above-mentioned conventional problems are solved.
In the first manufacturing method of the present invention, after the element is fixed to the support, the presence or absence of a short circuit between the electrode of the first semiconductor and the support of each element is inspected, and the result is determined as the support on which the element is mounted. It memorize | stores in the memory with the data regarding the position of the recessed part. Then, after forming an electrical insulating layer on the back surface of the support to which the element is fixed, a hole is formed in the electrical insulating layer to expose the electrode, and the respective electrodes of each element are electrically connected to each other.

  At this time, from the data on the position of the concave portion of the support body stored in the memory and the data on the presence or absence of a short circuit of the element mounted thereon, for the element in which the first semiconductor and the support body are short-circuited, Do not drill holes in the electrical insulation layer.

  When the element is mounted to be inclined with respect to the hole of the support, and the electrode of the first semiconductor of the element and the support are in contact with each other, a hole is formed in the electrical insulating layer, and the hole is filled with a conductive paste. The support of the photoelectric conversion device and the first conductor layer are short-circuited so that the output cannot be taken out. In the present invention, since no hole is formed in such an element, a situation in which the photoelectric conversion device malfunctions can be prevented.

  Furthermore, the position where the hole is made is determined in advance as a position corresponding to the central portion of the concave portion of the support. Therefore, there is no misalignment as in the case where an electrical insulating layer provided with a hole for connecting the electrode and the first conductor layer is bonded to the support. Further, the first semiconductor electrode and the first conductor layer can be electrically and reliably connected by a relatively simple method of opening a hole and filling the conductive paste therewith.

  Next, in the second manufacturing method of the present invention, as in the first manufacturing method, after the element is fixed to the support, the presence or absence of a short circuit between the first semiconductor electrode of each element and the support is inspected. The result is stored in a memory together with data relating to the position of the concave portion of the support on which the element is mounted. After that, after bonding the conductive metal sheet and the electrically conductive metal sheet to the back surface of the support to which the element is fixed, and separating the support, the conductive metal sheet and the electrical insulating layer are perforated. Then, the electrodes are exposed and filled with a conductive paste, whereby electrical connection between each electrode of each element and the first conductor layer is performed.

  At this time, from the data regarding the position of the concave portion of the support stored in the memory and the data regarding the presence or absence of a short circuit of the element mounted on the memory, for the element in which the first semiconductor and the support are short-circuited, Do not perforate the metal sheet and electrical insulation layer.

  According to this method, a situation in which the photoelectric conversion device malfunctions can be prevented, and effects similar to those of the first manufacturing method can be obtained, such as no misalignment.

  On the other hand, in the third manufacturing method of the present invention, unlike the first and second manufacturing methods, first, an electrical insulating layer is formed on the back surface of the support to which the element is fixed, and holes are formed in the electrical insulating layer. Expose the electrode. Thereafter, the hole is filled with a conductive paste, the presence or absence of a short circuit between the conductive paste and the support is inspected, and the result is stored in a memory together with data on the position of the concave portion of the support on which the element is mounted. .

  At this time, from the data on the position of the concave portion of the support stored in the memory and the data on the presence or absence of a short circuit of the element mounted thereon, the element in which the conductive paste and the support are short-circuited is filled in the hole. Cover the resulting conductive paste with an insulator. Thereafter, the electrodes of each element are electrically connected to each other, except for the element in which the conductive paste is covered with an insulator.

  In the first and second manufacturing methods, since the stylus directly touches the element during the inspection, there is a risk that the position of the element may be displaced, poor contact with the support, or dropping off. According to this manufacturing method, the element is firmly supported by the support by the electrical insulating layer, and the possibility that the element is displaced or dropped in the inspection process can be suppressed.

  Further, in the fourth manufacturing method of the present invention, after fixing the element before forming the electrode to the support, the second semiconductor layer of the element exposed to the back side from the hole of the support is removed to remove the first semiconductor. A part is exposed, and then an electrical insulating layer is formed on the back surface of the support, and a hole is formed in the electrical insulating layer to expose the first semiconductor of the element. Furthermore, after filling the hole with a conductive paste, heat treatment is performed to form an electrode, the presence or absence of a short circuit between the electrode and the support is inspected, and the result is determined as the position of the concave portion of the support on which the element is mounted. Store in memory with data about In addition, you may apply | coat a conductive paste on an electrode as needed, and may test | inspect the presence or absence of the short circuit between an electrode and a support body through the conductive paste.

  At this time, based on the data on the position of the concave portion of the support stored in the memory and the data on the presence / absence of a short circuit of the element mounted on the memory, for the element in which the electrode and the support are short-circuited, the electrode should be cover. Finally, the electrodes of each element are electrically connected to each other, except for the elements whose electrodes are covered with an insulator.

  When an electrode is formed by locally irradiating the conductive paste applied to the exposed portion of the first semiconductor with a laser, a resin component (such as an organic vehicle) in the conductive paste applied to the exposed portion of the first semiconductor. ) Decomposes rapidly. A part of the conductive paste is easily scattered around by the physical momentum at that time. In rare cases, the scattered conductive material such as Ag powder adheres to the conductive adhesive at the periphery of the hole of the support or the edge of the hole, and the electrode and the support (second conductive layer) are short-circuited. . In the fourth manufacturing method, since the conductive paste is filled in the holes, the scattering during the laser irradiation stays in the holes and a short circuit can be prevented.

  Moreover, in the fifth manufacturing method of the present invention, after fixing the element before forming the electrode to the support, an electrical insulating layer is formed on the back side of the support, and a hole is formed in the electrical insulating layer to form the element. A portion of the second semiconductor layer is exposed, and the exposed second semiconductor layer is removed to expose a portion of the first semiconductor of the device, and a conductive paste is applied to the surface of the first semiconductor exposed in the hole. Then, heat treatment is performed to form an electrode. Thereafter, the presence or absence of a short circuit between the electrode and the support is inspected, and the result is stored in a memory together with data on the position of the concave portion of the support on which the element is mounted.

  At this time, based on the data on the position of the concave portion of the support stored in the memory and the data on the presence / absence of a short circuit of the element mounted on the memory, for the element in which the electrode and the support are short-circuited, the electrode is made of an insulator. cover. Thereafter, the electrodes of the respective elements are electrically connected to each other except for the elements whose electrodes are covered with an insulator.

The fifth manufacturing method has an effect of preventing a short circuit during laser irradiation as in the fourth manufacturing method. Furthermore, when the second semiconductor layer is removed by a method such as etching, the support is masked by the electrical insulating layer, so there is no concern that the support will be damaged by etching or the like.
As described above, according to each manufacturing method of the present invention, a photoelectric conversion device suitable for mass production can be provided.

(Embodiment 1)
Hereafter, each process of the manufacturing method of the photoelectric conversion apparatus in Embodiment 1 of this invention is demonstrated in detail with reference to drawings.

1) Step of preparing a structure in which a photoelectric conversion element is mounted in a concave portion of a support (1)
In this step, a. Preparing a photoelectric conversion element; b. Forming a first semiconductor electrode; c. Providing a support; and d. A structure in which the photoelectric conversion element is mounted in the concave portion of the support is prepared by each step of mounting the photoelectric conversion element on the support.

1-a) Step of Preparing Photoelectric Conversion Element In this step, a substantially spherical photoelectric conversion element shown in FIG. 1A is prepared, which includes a spherical first semiconductor and a second semiconductor layer covering the surface thereof. For example, the spherical first semiconductor is manufactured as follows.

  First, a p-type polycrystalline Si lump containing a very small amount of boron is supplied into a crucible and melted in an inert gas atmosphere. The melt is dropped from a minute nozzle hole at the bottom of the crucible, and the droplet is cooled and solidified during natural fall. In this manner, a polycrystalline or single crystal spherical p-type semiconductor can be manufactured.

  After polishing the surface of the spherical p-type semiconductor produced as described above and further removing about 50 μm of the surface layer by etching or the like, for example, using phosphorus oxychloride as a diffusion source at 800 to 950 ° C. for 10 to 30 minutes Heat treatment. As a result, an n-type semiconductor layer having a thickness of about 0.5 μm in which phosphorus is diffused on the surface of the p-type semiconductor is formed as the second semiconductor layer. The n-type semiconductor layer can also be formed by a CVD method using a mixed gas such as silane containing phosphine.

After forming the second semiconductor layer, an antireflection film may be formed on the second semiconductor layer. In this case, in the subsequent step (1-d), the second semiconductor layer and the support (second conductor layer) are electrically connected via the antireflection film. Therefore, the antireflection film in the present invention needs to have conductivity, for example, ZnO, SnO ₂ and ITO (In ₂ O ₃ —Sn) formed by a solution deposition method, an atomization method or a spray method. A thin film mainly composed of such as can be used.

  The first semiconductor is preferably a true sphere, but may be substantially spherical. In other embodiments, the first semiconductor may be one in which the outer periphery of the core is covered with the first semiconductor layer, and the vicinity of the center of the first semiconductor may be a cavity. The diameter of the spherical element 7A is suitably 0.5 to 2 mm, more preferably 0.8 to 1.2 mm. This makes it possible to obtain a spherical element that uses a small amount of expensive material such as high-purity Si, generates a large amount of electric power, and is easy to handle.

  In the above embodiment, the spherical element 7A in which the first semiconductor is a p-type semiconductor and the second semiconductor layer is an n-type semiconductor layer is shown. However, the first semiconductor is an n-type semiconductor and the second semiconductor layer is It may be a p-type semiconductor layer. In the above embodiment, a spherical element made of a crystalline Si semiconductor is exemplified, but it may be made of a compound semiconductor or other material, and may be made of an amorphous material other than a single crystal or polycrystal. Further, it may have a pin type structure in which a non-doped layer is formed at the interface between the first semiconductor layer and the second semiconductor layer, a MIS type, a Schottky barrier type, a homojunction type, or a heterojunction type. Good.

1-b) Step of Forming Electrode of First Semiconductor In this step, a part of the first semiconductor of the spherical element is exposed from the second semiconductor layer, and an electrode is formed on the exposed portion.

  In the previous step (1-a), a second semiconductor layer is formed on the surface of the spherical first semiconductor, an antireflection film is formed as necessary, and a part thereof is removed by grinding, for example, by grinding. Thus, an opening is formed in the second semiconductor layer, and a part of the first semiconductor is exposed. This process is shown in FIGS. 1 (a) and (b). A part of the spherical first semiconductor 1 covered with the second semiconductor layer 2 is cut off, and an opening 3 of the second semiconductor layer is formed on the outer periphery of the smooth cut surface. A circular exposed portion 4 is formed. The central angle θ connecting the outer peripheral portion of the opening from the central point of the spherical element 7B in FIG. 1B may be 45 to 90 °, and preferably 60 to 90 °. Thereby, after reducing the quantity of the waste material by cutting, the suitable opening part area required for the electrical connection of a 1st semiconductor and a 1st conductor layer is obtained.

  The electrode on the first semiconductor side can be formed, for example, by applying a conductive paste to the exposed portion of the first semiconductor and performing a heat treatment. When the first semiconductor is a p-type semiconductor, generally a glass frit type conductive paste in which a conductive material in which Al powder or Ag powder is mixed is dispersed is used. When the first semiconductor is an n-type semiconductor, it is preferable to use a mixture of a phosphorus compound and Ag powder as the conductive material. A good conductive layer (electrode) can be formed by drying the applied conductive paste at about 100 ° C. for about 10 minutes and then performing heat treatment at 650 to 750 ° C. for about 10 minutes.

  By the heat treatment, the conductive material in the conductive paste diffuses into the first semiconductor to form a diffusion layer or an alloy layer with Si, and an electrode is formed using the molten glass frit as a binder. Due to the action of the diffusion layer and the alloy layer, the contact resistance of the junction between the first semiconductor and the electrode is reduced. 1C is a longitudinal sectional view of a spherical element 7C in which a circular electrode is formed on the exposed portion of the first semiconductor of the spherical element 7B of FIG. 1B, and FIG. 2 is a bottom view thereof. The electrode 5 is formed by applying a conductive paste to a circular portion having a diameter of about 300 μm at a center of the exposed portion 4 of the first semiconductor of the spherical element of FIG. Can be formed. The conductive paste can be applied by screen printing, offset printing, or inkjet method. The shape of the electrode is not particularly limited, and may be an ellipse, a polygon, a ring, or a set of points other than a circle.

1-c) Step of preparing support In this step, the spherical element prepared in the previous step (1-b) has a large number of recesses for placing inside, and the second semiconductor layer of the spherical element is electrically A support that also serves as the second conductor layer to be connected is prepared. As a typical example of this support, FIG. 3 shows a partial plan view of a support prepared by pressing an Al thin plate having a thickness of 0.2 mm, and FIG. 4 shows a sectional view taken along the line IV-IV. The concave portion 11 of the support 10 is formed in a honeycomb shape, and its open end is hexagonal. The open ends are adjacent to each other, and the concave portion 11 becomes narrower toward the bottom. The hole 12 formed in the bottom of the recess 11 is smaller than the diameter of the spherical element 7C, but has a diameter substantially the same as or slightly larger than the opening 3 of the second semiconductor layer. The hole 12 may be circular or other shapes, but is preferably similar to the exposed portion of the first semiconductor.

  By connecting the second semiconductor layer to the edge of the hole of the support in the subsequent step (1-d), the support functions as a conductor on the second semiconductor side (second conductor layer). The second semiconductor layer of each of the spherical elements mounted on is electrically connected in parallel. Therefore, at least the light receiving surface side of the support used here needs to have conductivity.

  If a material having poor heat resistance is used for the support 10, it is likely to be deformed or altered by a heat treatment step after positioning the spherical element. Therefore, it is preferable to use a material that can ensure heat resistance such as metal. As the main material of the support, Al is preferable in terms of workability, conductivity, flexibility, cost, and the like, but other conductive materials such as Cu, stainless steel, and Ni may be used. By forming a plated layer of Ag or the like excellent in conductivity and light reflectivity on the surface, the functions as the conductor layer and the reflecting mirror can be enhanced.

  The support as illustrated in FIG. 3 mainly composed of a metal material is used when, for example, connecting a second semiconductor layer and a second conductor layer in a later step, for example, a low-temperature glass frit type conductive paste and a resin type conductivity. No matter which paste is used, it is not damaged by the heat treatment. For example, in the case of a normal support mainly composed of Al, there is no problem even if the maximum temperature of the heat treatment reaches 550 ° C. On the other hand, when using a composite support of a resin substrate and a metal thin film, it is preferable to use a resin-type conductive paste that can be heat-treated at a relatively low temperature.

1-d) A process of mounting the photoelectric conversion element on the support In this step, the part extending from the electrode to the outer peripheral edge of the opening of the second semiconductor layer is located on the edge of the hole of the support. The second semiconductor layer and the support are electrically connected to each other so that the second semiconductor layer is exposed to the back surface side of the substrate and the second semiconductor layer is in contact with the inner surface of the concave portion of the support.

  In more detail, the preferred step is a step of applying a conductive adhesive to the support 10, as shown in FIG. 5, so that the photoelectric conversion element 7 is suitable for mounting in the hole 12 of the support 10. As shown in FIG. 6, the photoelectric conversion element 7 with the adjusted orientation, the step of mounting the photoelectric conversion element 7 on the support 10, and the step of solidifying the conductive adhesive.

  First, the conductive adhesive 13 is applied to the peripheral portion of the hole 12 provided at the center of the concave portion of the support 10 by screen printing. Specifically, a metal mask (not shown) in which a plurality of openings are arranged along the opening end of the hole 12 is used, and the portion extending from the outside of the opening end of the hole 12 of the support 10 to the inside of the hole is used. The paste-like conductive adhesive 13 is printed. The adhesive applied to the portion corresponding to the outside of the open end of the hole 12 is transferred onto the peripheral edge of the hole 12, and the other adhesive portion connected to the transfer portion falls into the hole 12, and further the end thereof. The part adheres to the opposite surface of the support 10. Thus, the conductive adhesive 13 divided into a plurality along the opening end of the hole 12 is applied to the support 10.

  Next, the spherical element 7C shown in FIG. 1C prepared in the step (1-b) is mounted on the support 10 after the posture is adjusted as shown in FIG. As a method of adjusting the posture of the spherical element 7C and mounting it on the support 10, the element 7 as disclosed in Patent Document 2 is sucked with a metal tube from the side opposite to the opening side, and the support 10 Using a substrate having a number of depressions in a pattern corresponding to the arrangement pattern of the depressions 11 of the support 10 and storing the spherical element 7C in each depression, with the opening end side facing up. After adjusting the posture, there is a method of pushing up and attaching to the concave portion 11 of the support body 10 with an extruding bar from a hole under the recess. Any method is selected in consideration of productivity, mounting accuracy, and the like.

  Thereafter, by heat treatment, the conductive adhesive is solidified and the element 7 is fixed to the support 10. At the same time, the support 10 as the second conductor and the second semiconductor layer 2 are electrically connected.

  In the step (1) described above, after forming the electrode on the photoelectric conversion element, the element is mounted in the concave portion of the support. On the contrary, the element electrode is mounted after mounting the element in the concave portion of the support. It is also possible to employ a method of forming Specifically, a structure in which the photoelectric conversion element is mounted in the concave portion of the support is prepared by the following steps (1-e) to (1-i).

1-e) A step of preparing a plurality of substantially spherical photoelectric conversion elements composed of a spherical first semiconductor and a second semiconductor layer covering the surface thereof In this step, as described in the above step (1-a) A substantially spherical photoelectric conversion element is prepared by the same method.

1-f) A step of preparing a conductive support having a plurality of adjacent concave portions for arranging the photoelectric conversion element therein and having a hole smaller than the photoelectric conversion element at the bottom portion. A support having a large number of recesses is prepared by the same method as described in 1-c).

1-g) A process of attaching the photoelectric conversion element to each recess of the support and electrically connecting the second semiconductor layer of the photoelectric conversion element to the support In this process, the photoelectric conversion element was prepared by the above-described process (1-a). The spherical element 7A is mounted on the support.

  First, the support 10 in which the conductive adhesive 13 is applied to the peripheral edge of the hole 12 is prepared by the same method as described in the step (1-d). Thereafter, a large number of substantially spherical elements 7A are dispersed on the support 10, and the spherical elements 7A are dropped one by one into the respective recesses 11 of the support 10, and the remaining elements are removed. The conductive adhesive 13 is pressed to adhere to the support 10. Thereafter, by conducting a heat treatment, the conductive adhesive 13 is solidified and the spherical element 7A is fixed to the support 10, and at the same time, the support 10 as the second conductor and the second semiconductor layer 2 are electrically connected. . FIG. 7A shows a cross section in a state in which the spherical element 7A is fixed to the support 10.

  In the step (1-d) described above, since the electrode is formed on the element and then mounted on the support body 10, it is necessary to mount the element on the support body 10 with the attitude of the element accurately controlled. Since there is no need for control, the number of manufacturing steps can be greatly reduced.

1-h) Step of removing the second semiconductor layer of the photoelectric conversion element exposed on the back side from the hole of the support to expose a part of the first semiconductor In this step, the hole of the support 10 is formed by, for example, sandblasting. The second semiconductor layer 2 of the spherical element 7A exposed from 12 is removed. Specifically, a fine powdery abrasive made of alumina is sprayed from the nozzle together with air on the back side of the support 10 on which the element 7A is mounted, and the surface layer of the element 7A exposed from the hole 12 (depth about 1 to about 1). 3 μm) is scraped off together with the second semiconductor layer 2 with an abrasive to expose the first semiconductor 1. FIG. 7B shows a cross section of the spherical element 7D from which the second semiconductor layer 2 has been removed.

  In the sandblasting method, a hard material such as silicon is polished, but a soft material such as an aluminum support or conductive adhesive is difficult to polish, so only the element surface on the back side of the support 10 is selected. Polished and removed. Therefore, according to this method, a very thin diffusion layer on the surface of the element 7D is removed, and the outer shape of the element 7D remains almost spherical. Further, the second semiconductor layer 2 is removed up to the periphery of the hole 12 of the support 10 or the application portion of the conductive adhesive 13.

  After polishing, if necessary, the polished surface is lightly etched with a mixed solution of nitric acid-hydrofluoric acid so that subsequent electrode formation is easy and the solar cell characteristics are not impaired, and then washed with water.

1-i) Step of forming electrode on exposed portion of first semiconductor In this step, as shown in FIG. 7 (3), the conductive paste 14 is exposed to the exposed portion of the first semiconductor 1 using a printing method or a dispenser. After the coating, an electrode is formed by locally irradiating a laser on the coating part and locally heating it. The laser irradiation can be performed, for example, using a YAG laser device at a scanning speed of 1000 mm / sec and a printing pulse cycle of 10 μm.
Note that a glass frit-type conductive paste that can withstand heat treatment by a laser is preferably used as the conductive paste.

  According to the method of steps (1-a) to (1-d) described above, electrode formation of the first semiconductor requiring heat treatment at a high temperature is performed at the element stage, and the second semiconductor layer and the support are formed. The electrical connection is performed when the support does not have an electrical insulating layer. Therefore, the support and the electrical insulating layer bonded thereto are not damaged by the heat treatment, but a short circuit between the electrode and the support may occur due to the displacement of the element mounting.

On the other hand, according to the methods of the steps (1-e) to (1-i), the alignment of the elements is not necessary, so that the process at the time of mounting is simplified and the productivity is increased. If the paste application position shifts or the coating layer comes off and comes into contact with the support, a short circuit between the electrode and the support occurs.
Which method is to be adopted is determined after comparing the merits and demerits of each method.

2) Inspecting for short circuit between electrode and support (2)
In this step, using the mounting inspection system shown in FIG. 10, the element 7 is accurately positioned and attached to the hole 12 of the support 10, and the electrode 5 and the support 10 or the conductive adhesive 13 are not in contact with each other. Whether the electrode 5 and the support 10 or the conductive adhesive 13 are not in contact with each other due to the displacement of the electrode 5 when the electrode 5 is formed after the element 7A is mounted on the support 10. .

  FIG. 8 is a plan view of a support in which an element in which an electrode is formed in advance is mounted in the hole, and FIG. 9 is a cross-sectional view taken along the line VV in FIG. Like the element at the right end of FIGS. 8 and 9, the spherical element 7 </ b> C may be mounted in a tilted state with respect to the support 10 in the previous step (1-d). In this case, the electrode 5 of the element 7 </ b> C and the support 10 are in direct contact with each other via the conductive adhesive 13, and a short circuit occurs between the electrode 5 and the support 10. In the subsequent steps (4) and (5), holes are formed in the electrical insulating layer for such elements 7C and the respective electrodes of the elements are electrically connected. One conductor layer is short-circuited, and the output cannot be taken out. Even when the electrode 5 is formed after the element 7A is mounted on the support 10, the electrode 5 of the element 7C contacts the support 10 or the conductive adhesive 13 due to the displacement of the electrode 5, and the electrode 5 and the support 10 A short circuit occurs between the two.

  In order to prevent a short circuit of the photoelectric conversion device, in this step, the presence or absence of a short circuit between the electrode 5 and the support 10 is inspected for each element, and the result is determined as the position of the recess 11 of the support 10 on which the element 7C is mounted. Store in memory with data. About the element 7C in which a short circuit is recognized, the occurrence of a situation where it does not function as a photoelectric conversion device is prevented in advance by stopping drilling of the electrical insulating layer in the subsequent step (4).

  Hereinafter, this process will be described with reference to FIG. The mounting inspection system includes a short circuit inspection device 20, a constant voltage device 21, a current measurement device 22, and an information processing device 23.

  The short-circuit inspection apparatus 20 inspects a short circuit between the electrode 5 of each element and the support 10 by bringing a stylus into contact with the electrode of the element 7C. Specifically, the stage 10 is placed on the base 24, the support 10 as the subject is placed on the stage 24, the stage 25 is movable in a direction (X-axis direction) perpendicular to the paper surface, and is fixed to the base 24. An electric cylinder 27 supported by the support column 26 and movable in the vertical direction; a contact probe 28 which is held at the lower part of the electric cylinder 27 and has a number of styluses 29 corresponding to the number of recesses of the support 10 at the tip. , Rotating a ball screw attached to the stage 25 to move the stage 25 in the X-axis direction, a sequencer 31 for moving the stage 25 to a predetermined position by controlling the driver 30, and control of the sequencer 31 The relay 32 is configured to select one of a plurality of styluses 29 provided on the contact probe 28 below.

  The current measuring device 22 measures the current supplied from the constant voltage device 21 and flowing between the stylus 29 selected by the relay 32 and the support 10. The information processing device 23 reads out the data related to the position of the central portion of the concave portion 11 of the support 10 stored in the memory 33 and provides it to the sequencer 31, and the presence / absence of short circuit of each element 7 </ b> C measured by the current measuring device 22. Is stored in the memory 33. Usually, a personal computer is used for the information processing device 23, and a hard disk built in the personal computer is used for the memory. Reference numeral 34 denotes a cable for electrically connecting the above devices.

  In the inspection, first, the support body 10 in which the element 7C is mounted in the recess 11 manufactured in the previous step (1) is fixed on the stage 25 with the recess 11 facing up. The stage 25 is provided with guide pins 35 at four locations, and the support 10 is accurately positioned on the stage 25 by inserting the guide pins 35 into the positioning holes formed at the four corners of the support 10. Is done. The position of each concave portion 11 of the support 10 is specified as a coordinate position where the X axis and the Y axis are defined by the four positioning holes.

  Note that the number of styluses 29 attached to the contact probe 28 is equal to the number of the concave portions 11 arranged in the Y-axis direction of the support 10, and the interval is also equal to the interval between the concave portions 11.

  After the support 10 is fixed on the stage 25, the driver 30 is driven according to the control of the sequencer 31, and the first row of the recesses 11 of the support 10 faces the stylus 29 of the contact probe 28. Move to position. Next, according to the control of the sequencer 31, the electric cylinder 27 is lowered to bring the individual stylus 29 into contact with the electrode of the element 7 </ b> C mounted in the concave portion 11 of the support. Thereafter, one of the stylus 29 is selected by the relay 32, and the current flowing between the element 7 </ b> C and the support 10 is measured by the current measuring device 22.

  When the element 7C is mounted in the hole 12 of the support body 10 in the correct posture, the element 7C and the support body 10 are insulated and no current flows, but as shown on the right side of FIG. When mounted on the support 10 at an angle, the electrode 5 of the element 7C and the support 10 are short-circuited, and a current flows. Therefore, it is possible to inspect whether the electrode 5 of the element 7 </ b> C is short-circuited with the support 10 by measuring the value of the current flowing through each element 7 </ b> C by the current measuring device 22. This inspection result is stored in the memory 33 as a pair with data on the center position of the concave portion of the support 10 via the information processing device 23 as presence / absence of a short circuit for each element.

  When the short circuit inspection is completed for all the elements 7C mounted in the recesses 11 in the first row of the support 10, the electric cylinder 27 moves upward and the stage 25 moves in the X-axis direction under the control of the sequencer 31. Then, the concave portion 11 in the second row of the support 10 stops at a position facing the stylus 29 of the contact probe 28, and then the electric cylinder 27 descends. By repeating the same operation, the presence or absence of a short circuit is inspected for all the elements 7 </ b> C attached to the recess 11 of the support 10, and the result is stored in the memory 33.

  In the present embodiment, the contact probe is used to inspect the presence or absence of a short circuit between the first semiconductor of the element and the support. However, after shooting the mounting state of the element 7C on the support 10 with a camera, Using a recognition device, the presence or absence of contact between the electrode 5 of the element 7C and the peripheral edge of the support 10 or the conductive adhesive 13 connected to the periphery is inspected, and the electrode 5 and the support 10 are connected to the periphery or the periphery. When the conductive adhesive 13 is in contact, it is highly possible that a short circuit will occur between the electrode 5 and the support.

  In an inspection using a contact probe, it is necessary for all the styluses arranged in a row to contact the element reliably. If the contact is insufficient, the presence or absence of a short circuit may not be accurately determined. Such a situation does not occur when the recognition device is used. On the other hand, in the case of using an image recognition device, generally, since one device is moved to photograph the mounting state of each element, there is a disadvantage that the inspection time becomes longer than when a contact probe is used. Which method is adopted is determined in consideration of the accuracy required for the inspection and the time required for the inspection.

3) Step of forming an electrical insulating layer on the back side of the support (3)
In this step, an electrical insulating layer is formed on the back side of the support on which the spherical element is fixed at a predetermined position in step (1). As a method for forming the electrical insulating layer at a high speed, there is a method in which a resin paste is applied and dried by a screen printing method, a spray method, an offset printing method, an ink jet method or the like. As the material of the resin paste, various resins such as epoxy, polyimide, silicone, urethane, and acrylic can be used. In view of cost and workability, it is most preferable to use an epoxy resin. The resin paste is obtained by dissolving or dispersing the above resin material in an organic solvent or water.

  The screen printing method and the offset printing method have an advantage that pattern printing can be performed at high speed. In order to uniformly apply the resin paste by these printing methods, it is preferable to reduce the unevenness of the coated surface on the back side of the support. The spray method is most preferable from the viewpoints of facility simplicity and productivity, and can form an electrically insulating layer at low cost.

  FIG. 11 illustrates an embodiment of a process of applying a resin paste to form an electrical insulating layer. In this embodiment, a resin paste is applied to the back side of the support by a spray method and heat-treated, and then a part of the electrode is exposed by laser light irradiation. As the resin paste, for example, an epoxy resin (manufactured by Jujo Chemical Co., Ltd .: MIG-N) is dispersed in a glycol ester solvent, and the viscosity is about 20 Pa.s. What was adjusted so that it might become s can be used.

  FIG. 11A shows a resin paste application process. The support body 10 to which the positioned spherical element 7C shown in FIG. 6 is fixed is arranged so that the light receiving surface is downward, and the resin paste 42 is sprayed in a mist form from the nozzle 41 of the upper spray coating apparatus. The nozzle 41 is moved from the left to the right, and the spherical element 7C (the opening 3 and its peripheral portion of the second semiconductor layer, and the exposed portion 4 and the electrode 5 of the first semiconductor layer) at the portion exposed on the back surface side of the support 10 is shown. And a coating layer 43 of a resin paste having a thickness of about 30 μm is formed on the entire back surface of the support 10.

  Next, the coating layer 43 is subjected to a heat treatment at about 150 ° C. for about 30 minutes to form an electrical insulating layer 44 as shown in FIG. The adhesion between the electrical insulating layer 44 and the back side of the support 10 is very good, and the support 10 and the exposed portion 4 of the first semiconductor are electrically completely insulated.

  As another embodiment of forming an electrical insulating layer, there is a method in which an electrical insulating layer is formed using a resin sheet such as polyether ether ketone, and then a laser beam is irradiated to expose a part of the electrode. The support body 10 to which the spherical element is fixed is disposed so that the light receiving surface faces down, and the resin sheet is disposed so as to cover the entire back surface side of the support body 10. Next, the resin sheet is brought into close contact with the support by heat treatment.

  Even when a thin resin sheet having a thickness of about 50 μm is used, the adhesion to the back side of the support 10 is very good, and the support 10 and the exposed portion 4 of the first semiconductor are electrically completely insulated. There is a part of the gap between the resin sheet and the back surface of the support 10. However, if the thickness of the resin sheet is 50 μm or more, the strength is sufficient.

4) Step of exposing the electrode by opening a hole in the electrical insulating layer (4)
In this step, a hole for exposing the electrode 5 of the element 7 </ b> C is formed in the electrical insulating layer 44.
In the state of FIG. 11 (2), in order to expose the electrode 5 of the first semiconductor 1 of the element 7C, a laser beam 45 is irradiated to a portion corresponding to the center of the hole 12 as shown in FIG. The electrical insulating layer 44 is partially removed to form a hole 47.

  Similar to the above-described inspection step (2), the support 10 is fixed on the stage 25. The information processing device 23 reads out data related to the center position of the concave portion 11 of the support 10 stored in the memory 33 and provides the sequencer 31 with the data, and installs the laser light irradiation device 46 instead of the contact probe 28. An YAG laser with an output of 50 W is used as the laser irradiation device light 46, and the electrically insulating layer in the irradiated region having a diameter of about 100 to 150 μm can be removed in an irradiation time of about 0.01 seconds.

  As described in the step (2), for the element 7C in which the electrode 5 and the support 10 are short-circuited, the support 10 and the first conductor layer 1 are short-circuited and the function as a photoelectric conversion device is impaired. In order to prevent this, no hole is made and the electrode 5 is not exposed.

5) Step of electrically connecting the electrodes of the plurality of photoelectric conversion elements to each other (5)
In this step, among the spherical elements fixed at predetermined positions on the support, the electrodes of the elements determined not to be short-circuited in step (2) are electrically connected by the first conductor layer. In this step, a first conductive layer is formed by applying a conductive paste on the electrical insulation layer so that the electrodes of the spherical elements exposed from the electrical insulation layer are connected to each other and solidifying by heating. It is preferable that the process to include is included. A first conductive layer is constituted by the solidified conductive paste, and the first semiconductor layer electrodes of the spherical elements fixed to the support are electrically connected to each other by the first conductive layer.

  It is preferable to select a conductive paste that solidifies at a temperature at which the electrical insulating layer formed in the step (3) does not suffer damage such as deformation or alteration. In general, it is preferable to use a resin-type conductive paste that can be solidified at a relatively low heat treatment temperature of 100 to 200 ° C. When the electrical insulating layer is made of a material having relatively high heat resistance such as high melting point glass or fluorine resin, a low temperature glass frit type conductive paste can also be used. As a method for applying the conductive paste, there are a dispenser method, a screen printing method, an offset printing method, and a spray method. When the back surface of the support is uneven, it is necessary to apply a conductive paste to the recesses, and particularly when the recesses are deep, a dispenser method and a spray method are preferable.

FIG. 12 shows a specific embodiment of a process of forming a first conductor layer by applying a conductive paste by a dispenser method and applying heat treatment, and electrically connecting each electrode.
First, a support shown in FIG. 11 (3) having an electrical insulating layer 44 formed on the back side is prepared. Then, as shown in FIG. 12 (1), while discharging the conductive paste 49 from the nozzle 48 of the dispenser, the nozzle 48 is moved along a straight line connecting the electrodes 5 of the spherical elements exposed from the electrical insulating layer 44. Then, a linear conductive paste coating layer 50 is formed on the electrical insulating layer 44 as shown in FIG. Thereby, each electrode 5 of a large number of spherical elements fixed to the support 10 is connected by the conductive paste coating layer 50 via the electrical insulating layer 44 on the back surface side of the support 10.

  When applying the conductive paste with a dispenser, a conductive paste coating layer having an appropriate line width and no disconnection can be formed by appropriately adjusting the moving speed according to the inner diameter of the nozzle. For example, when the nozzle inner diameter is 0.15 mm and the head moving speed is 80 mm per second, the line width of the conductive paste coating layer is 490 μm, the nozzle inner diameter is 0.1 mm, and the head moving speed is When it is set to 10 mm per second, a coating layer having a line width of 310 μm is formed. In any of the coating layers formed under these conditions, the electrodes are securely connected by the conductive paste without disconnection, despite the unevenness of the coated surface. Judging from the electrical characteristics of the solar cell, it is sufficient if the line width of the coating layer is 310 μm or more.

  There are various patterns in which the conductive paste is applied linearly, and an example is shown in FIG. FIG. 13 is a plan view of the back side of the support 10 on which the conductive paste coating layer 50 is formed by the process of FIG. For the sake of simplicity, details such as the electrode and the removal portion of the electrical insulating layer by the laser beam are omitted from the drawing. A linear conductive paste coating layer 50 is formed on the electrical insulating layer 44 so as to connect each electrode of the spherical element fixed to each of the concave portions 11 of the plurality of supports arranged in a straight line.

  The line width of the conductive paste coating layer 50 is slightly smaller than the diameter of the hole 12 in the concave portion of the support, and is substantially equal to the diameter of the exposed portion of the first semiconductor of the spherical element. A plurality of conductive paste coating layers 50 are formed in parallel on the electrical insulating layer 44. The leading ends of these conductive paste coating layers 50 are connected by a linear conductive paste coating layer 50A formed at the ends of the support.

  The coating pattern is relatively simple, has good workability, and consumes less material, which is preferable for cost reduction. However, regardless of this, for example, a linear conductive paste coating layer is formed in a mesh pattern, and each electrode is positioned at the intersection of each linear coating layer constituting the mesh pattern. By doing so, a more reliable electrical connection between the electrodes becomes possible.

The conductive paste application pattern illustrated the method of connecting each electrode with a linear conductive paste application layer, but in the present invention, the conductive paste application pattern includes all of the conductive paste fixed patterns to the support. Each electrode of the spherical element may have any pattern as long as it is insulated from the support and the second semiconductor layer by an electrical insulating layer and connected in some form with a conductive paste. For example, a conductive paste may be applied to the entire surface of the electrical insulating layer by a printing method. Further, more reliable electrical connection can be achieved by applying the conductive paste in a dotted or linear manner to the portion where the electrode surface is exposed in advance and then applying the conductive paste in a linear or planar manner.
In addition, after filling the hole 47 with a conductive paste, each electrode may be connected by a linear conductive paste coating layer, and in this way, the electrical connection between the electrodes can be performed more reliably.

  The conductive paste coating layer formed as described above is heat-treated under the above-described conditions to solidify the coating layer, whereby the first conductor layer that electrically connects the electrodes on the first semiconductor side is electrically connected. It is formed on the back side of the support via an insulating layer. According to this method, the step of electrically connecting the first semiconductor and the first conductor layer can be performed at high speed, and the number of components can be further reduced.

  In addition to the above, a method of connecting a separately prepared conductive metal sheet such as an Al foil to the electrode using a conductive paste, solder, or the like can be employed. In this case, after applying a conductive paste in a spot-like manner to the part where the electrode surface is exposed in advance, a method of applying a heat treatment by pressing a metal sheet such as Al on the electrical insulating layer, or conducting the conductive material filled in the holes For example, there is a method in which a conductive paste as an adhesive is applied so as to cover the conductive paste, and thereafter a metal sheet such as Al is pressure-bonded on the electrical insulating layer and heat-treated. Note that, instead of the conductive paste, the electrode and the metal thin plate may be joined using solder.

  As described above, in the manufacturing method according to the present embodiment, the electrical insulating layer is bonded to the back surface of the support to which the element is fixed. Next, a hole is formed in the electrical insulating layer to expose the electrode, and the conductive paste is applied to the surface of the electrode that is filled with a conductive paste and exposed in the hole. Electrical connection is made between the electrode and the first conductor layer (conductive paste or metal thin plate). As a result, the electrodes of each element are electrically connected.

  According to this method, the position where the hole is made is determined in advance as a position corresponding to the central portion of the concave portion of the support. Therefore, there is no misalignment as in the case where an electrical insulating layer provided with a hole for connecting the electrode and the first conductor layer is bonded to the support. Therefore, the problem of dimensional accuracy of the electrical insulating layer, which occurs when a conventional support having a two-layer or three-layer structure is used, is solved.

  The electrical connection between the first semiconductor electrode of the device and the first conductor layer can be performed by a relatively simple method of filling the portion provided with the hole with a conductive paste. .

(Embodiment 2)
The second embodiment is the same as the first embodiment until the step (2) for inspecting a short circuit between the electrode formed on the exposed portion of the first semiconductor of the element and the support, but the back surface of the support. After bonding the conductive metal sheet and the electrical insulation layer to the side, a hole is made in the conductive metal sheet and the electrical insulation layer at a location corresponding to the first semiconductor electrode of the element that was not short-circuited in the inspection of the step (2). In that the electrodes are exposed. Hereinafter, the steps after (3) different from the first embodiment will be described.

1) Step of bonding a conductive metal sheet and an electrical insulating layer to the back side of the support (3)
In this step, a conductive metal sheet and an electrically insulating layer that separates the conductive metal sheet and the support are bonded to the back side of the support on which the spherical element is fixed at a predetermined position in the previous step (1). This conductive metal sheet functions as a first conductor that connects the electrodes of the first semiconductor of the element in parallel to each other. The electrical insulating layer electrically insulates the first semiconductor side (first semiconductor and first conductor layer) and the second semiconductor layer side (second semiconductor layer and second conductor layer).
In a preferred method, first, an electrically insulating adhesive layer is formed on the back surface of the support, including the part of the element exposed from the hole, and the electrically insulating layer is formed on the upper side of the conductive metal sheet. A composite sheet bonded and integrated on one side is disposed, and the electrically insulating layer side is bonded to the support.

  As a method for forming an electrically insulating adhesive layer at a high speed, there is a method of applying a paste adhesive by a screen printing method, a spray method, an offset printing method, an ink jet method or the like. As the material for the electrically insulating adhesive, various resins such as epoxy, polyimide, silicone, urethane, and acrylic can be used. In view of cost and workability, it is most preferable to use an epoxy resin. These resin materials are dissolved or dispersed in an organic solvent or water to prepare a coating paste. The method for forming the electrically insulating adhesive layer on the back surface of the support is the same as the method for forming the electrical insulating layer on the back surface of the support described in the step (3) of the first embodiment. Therefore, the description is omitted here.

  As the composite sheet, a laminate of an electrically insulating sheet and a metal sheet is used. As the material for the electrical insulating sheet, polyimide, polyester, polyethersulfone, polyetheretherketone, aromatic polyamide, polyethersulfone, polyetherimide and fluorine resins should be used. Can do. An aluminum foil is preferably used for the metal sheet, but other metals such as a copper foil and a nickel foil can also be used. The metal sheet preferably has a low electrical resistance sufficient to function as the first conductor layer, and the thickness is preferably 10 to 100 μm, and the electrical insulating layer is preferably 10 to 100 μm. A preferable example is an aluminum sheet having a thickness of 10 μm obtained by bonding a polyethylene terephthalate film having a thickness of 100 μm.

This process will be described with reference to FIGS. 14A and 14B.
FIG. 14A (1) shows a state in which the element 7C is fixed to the edge of the hole 12 of the support 10 by the conductive adhesive 13 in the step (1). Next, as shown in FIG. 14A (2), an electrically insulating adhesive is applied to the back side of the support 10 to form an adhesive layer 51. Next, the composite sheet 52 in which the electrical insulating layer 54 is formed on the metal sheet 53 is disposed on the side of the support 10 where the adhesive layer 51 is formed, and the electrical insulating layer 54 side of the sheet 52 is supported on the support 52 while reducing the pressure therebetween. 10 is joined. As shown in FIG. 14B (4), the composite sheet 52 is in close contact with the adhesive layer 14 at a portion corresponding to the periphery of the portion where the element 7C is fixed.

  In the illustrated example, the back surface of the support 10 swells so that the portion of the hole 12 becomes the top corresponding to the recess 11. Therefore, the adhesive is applied to the back surface of the partition wall between the adjacent recesses, but the electrical insulating layer 54 is not in close contact.

  As described above, according to the method of bonding the metal sheet 53 having the electrical insulating layer 54 after applying the adhesive layer 51, when the support 10 is formed of a thin metal sheet, the gap between the recesses is determined. An adhesive is applied to the back surface of the partition wall. This adhesive layer exhibits the effect of reinforcing the partition walls of the support. The adhesive layer is useful for firmly fixing the element bonded to the hole portion of the support to the support.

  Another method of joining the composite sheet 52 in which the electrical insulating layer 54 and the conductive metal sheet 53 are integrated to the support 10 is to apply an adhesive to the electrical insulation layer 54 and use the coated surface as the back surface of the support 10. It is a method of pasting to. A heat-adhesive resin material can also be used for the electrical insulating layer 54. According to these methods, the adhesive layer does not adhere to the back surface of the partition between the concave portions of the support. After the metal sheet having the electrical insulating layer is bonded as described above, heat treatment for solidifying or curing the adhesive is performed as necessary.

  As yet another method of joining the conductive metal sheet to the support, an electrical insulating layer is formed on the support in the same manner as in the first embodiment, and then an insulating adhesive is used, or heat is applied. There are a method of sticking a conductive metal sheet to an electric insulating layer by pressure bonding, a method of sticking a conductive metal sheet to a support using an insulating adhesive as an electric insulating layer, and the like.

2) Step of exposing the electrode of the photoelectric conversion element by opening a hole in the electrical insulating layer and the conductive metal sheet (4)
In this step, a hole serving as a conductive path for electrically connecting the metal sheet serving as the first conductor layer and the electrode 5 of the element 7C is formed.

  In the state of FIG. 14B (4), in order to expose the electrode 5 of the first semiconductor 1 of the element 7C, the portion corresponding to the center of the hole 12 is irradiated with laser light, and the metal sheet 53, the electrical insulating layer 54, and the adhesive are bonded. The agent layer 51 is partially removed to form holes 55 (FIG. 14B (5)). Using a YAG laser with an output of 12 W as the laser irradiation apparatus, the electrically insulating layer and the conductive metal sheet in the irradiated region having a diameter of about 100 to 150 μm can be removed in an irradiation time of about 0.017 seconds. A specific method is the same as the method described in the step (4) of Embodiment 1, and thus description thereof is omitted here.

  As described in the above step (2), for the element in which the electrode 5 of the first semiconductor 1 and the support 10 are short-circuited, the support 10 and the conductive metal sheet 53 are short-circuited, so that the photoelectric conversion device is used. No hole is made to prevent the function of the sensor from being damaged.

3) Step of electrically connecting the electrode of the photoelectric conversion element and the conductive metal sheet (5)
In this step, the conductive paste 56 is filled in the hole 55 formed in the above-described step (4), and the metal sheet 53 and the electrode 5 are electrically connected (FIG. 14B (6)).

  As the conductive paste used here, it is preferable to select a paste that solidifies at a temperature at which the electrical insulating layer is not damaged such as deformation or alteration. In general, it is preferable to use a resin-type conductive paste that can be solidified at a relatively low heat treatment temperature of 100 to 200 ° C. When the electrical insulating layer is made of a material having relatively high heat resistance such as high melting point glass or fluorine resin, a low temperature glass frit type conductive paste can also be used. As a method for applying the conductive paste, there are a dispenser method, a screen printing method, an offset printing method, and a spray method.

  In the photoelectric conversion device obtained as described above, the spherical photoelectric conversion element is firmly fixed at a predetermined position in the concave portion of the support, and further, except for the element in which the support and the first semiconductor electrode are short-circuited, The first semiconductor of all the elements fixed to the support and the first conductor layer (conductive metal sheet), the second semiconductor layer and the second conductor layer (support) are reliably electrically connected. .

  In the manufacturing method in the present embodiment, a conductive metal sheet and an electrical insulating layer that separates the conductive metal sheet and the support are bonded to the back surface of the support to which the element is fixed. Next, except for the element in which the support and the first semiconductor electrode are short-circuited, a hole is formed in the conductive metal sheet and the electrical insulating layer to expose the electrode, and the conductive paste is filled therein to be exposed in the hole. By applying a conductive paste to the surface of the electrode, the first semiconductor electrode of the element and the first conductor layer are electrically connected. Thus, a photoelectric conversion device that is reliably insulated without short-circuiting between the first conductor layer and the second conductor layer can be manufactured.

  According to this method, in the same manner as in the first embodiment, there is no alignment problem as in the case where an electrical insulating layer provided with a hole for connecting the electrode and the first conductor layer in advance is bonded to the support. There is no matching. Therefore, the problem of dimensional accuracy of the electrical insulating layer, which occurs when a conventional support having a two-layer or three-layer structure is used, is solved.

  The electrical connection between the first semiconductor electrode of the device and the first conductor layer can be performed by a relatively simple method of filling the portion provided with the hole with a conductive paste. . Furthermore, both the first conductor layer and the second conductor layer are made of a metal sheet or the like. Therefore, when connecting the units of the photoelectric conversion device in which a large number of elements are fixed in series or in parallel, the conductor layers can be easily connected by spot welding, ultrasonic welding, laser welding, or the like.

(Embodiment 3)
In the first and second embodiments described above, the short circuit is inspected by bringing the probe stylus into contact with the electrode of the element mounted on the support. On the other hand, in the present embodiment, after forming an electrical insulating layer on the back side of the element mounted on the support, holes are formed in the electrical insulating layer corresponding to the centers of all the recesses of the support, and the first semiconductor electrode Is exposed, and the hole is filled with a conductive paste, and a short circuit is inspected. Hereinafter, the steps after (2) which are different from the first and second embodiments will be described.

1) Step of forming an electrical insulating layer on the back side of the support (2)
In this step, an electrical insulating layer is formed on the back side of the support on which the spherical element is fixed at a predetermined position. Since the method for forming the electrical insulating layer is the same as the method described in the step (3) of Embodiment 1, detailed description thereof is omitted.

2) Step of opening a hole in the electrical insulating layer and exposing the electrode of the photoelectric conversion element in the hole (3)
In this step, a hole for exposing the electrode of the element is formed in the electrical insulating layer. Since this step is the same as the method described in step (4) of the first embodiment except that holes are formed in the electrical insulating layer for all elements mounted on the support, detailed description thereof is omitted. . FIG. 15A shows a state where an electrical insulating layer 61 is formed on the back side of the support 10 and a hole 62 for exposing the electrode 5 of the spherical element is formed in the electrical insulating layer 61.

3) Step of filling the hole formed in the electrical insulating layer with the conductive paste (4)
In this step, the conductive paste is applied to the surface of the electrode exposed in the hole by filling the hole of the electrical insulating layer formed in the step (3) with the conductive paste. This step is for filling the conductive paste in the holes of the electrical insulating layer in the same manner as the method in which the conductive paste is filled in the holes of the electrical insulating layer and the conductive metal sheet in the step (5) of the second embodiment. Detailed description will be omitted. FIG. 15B shows a state in which the hole 62 is filled with the conductive paste 63.

4) A step (5) for inspecting the presence or absence of a short circuit between the conductive paste filled in the holes of the electrical insulating layer and the support.
In this step, the presence or absence of a photoelectric conversion element in which the electrode 5 and the support 10 are short-circuited through the conductive paste 63 filled in the holes 62 of the electrical insulating layer 61, and the conductive paste 63 and the support 10 are determined. Inspect for contact holes. In this step, the mounting inspection system shown in FIG.

  In the step (2) of the first embodiment, the presence or absence of a short circuit was inspected by bringing the stylus 29 of the contact probe 28 into direct contact with the electrode 5 of the element, but in this step, the gap between the conductive paste 63 and the support 10 is examined. It differs in that it checks for the presence of a short circuit. When the hole 62 is formed in the electrical insulating layer 61, the position of the hole 62 may be shifted, and the second semiconductor layer 2 and the conductive adhesive 13 of the element 7C may be exposed in the hole 62. When such a hole 62 is filled with the conductive paste 63, a support which is a first conductor layer and a second conductor layer to be formed later will be short-circuited and will not function as a photoelectric conversion device. When a short circuit is inspected before the electrical insulating layer is formed as in the first embodiment, such a situation cannot be dealt with, but in this embodiment, such a situation can also be dealt with. Since the other points are the same as those of the method of the first embodiment, detailed description is omitted.

5) Step of covering the hole with short circuit between the conductive paste filled in the hole and the support with an insulator (6)
In this step, the conductive paste 63 filled in the hole 62 is covered with an insulator 64 for the element 7C that has been short-circuited in the inspection step (5).

  As described in the step (2) of the second embodiment, when the element 7C is not accurately positioned and attached to the hole 12 of the support 10, the electrode 5 of the element 7C and the support 10 are in contact with each other. A short circuit occurs between the first semiconductor 1 and the support 10. When the conductive paste 63 is filled in the hole 12 for such an element 7 </ b> C, a short circuit occurs between the conductive paste 63 and the support 10. Further, when the second semiconductor layer 2 and the conductive adhesive 13 of the element 7C are exposed in the hole 62 due to the positional deviation between the hole 62 formed in the electrical insulating layer 61 and the hole of the support 10, the conductive paste A short circuit occurs between 63 and the support 10. As described above, when a short circuit occurs between the conductive paste 63 and the support 10, the output of the completed photoelectric conversion device cannot be taken out.

  Therefore, by covering the conductive paste 63 of the shorted element 7C with the insulator 64, when the electrodes of the respective elements 7C are electrically connected in the next step, the shorted element 7C is eliminated. The occurrence of a situation where the completed photoelectric conversion device stops functioning is prevented. FIG. 15 (3) shows a state where the conductive paste 63 is covered with the insulator 64.

  The method of covering the conductive paste 63 filled in the holes 62 with the insulator 64 is basically a method of forming an electrical insulating layer on the back side of the support described in the step (3) of the first embodiment. In this step, it is preferable to employ a dispenser method or an ink jet method in order to apply an insulator only to a specific portion. In that case, the location which apply | coats an insulator is specified using the data regarding the position of the element 7C with the short circuit detected by the test process (5).

6) Step of electrically connecting the electrodes of the first semiconductor of the photoelectric conversion element in parallel via the conductive paste filled in the holes (7)
In this step, the electrodes 5 of the element 7C are electrically connected in parallel except for the element that was short-circuited in the inspection step (5). As a specific method, as described in the step (5) of the first embodiment, the conductive paste is applied on the electrical insulating layer 61 so as to connect the conductive paste 63 filled in the holes of the respective elements 7C. There is a method and a method in which a metal sheet similar to that used in the step (3) of Embodiment 2 is bonded to the electrical insulating layer 61 through a conductive adhesive. The method for applying the conductive paste is the same as the method described in the step (5) of Embodiment 1, and thus detailed description thereof is omitted.

  When using a metal sheet, the metal sheet is bonded to the electrical insulation layer via a conductive adhesive, and then heat treated to solidify the conductive paste and conductive adhesive filled in the holes of the electrical insulation layer. And while a metal sheet is fixed to a support body, the electrode of each element and a metal sheet are electrically connected. FIG. 15 (4) shows a state where the metal sheet 65 is bonded to the electrical insulating layer 61 via the conductive adhesive 66.

  As the conductive adhesive, a conductive paste using a thermosetting resin applied to the periphery of the hole of the support as a binder, or a conductive paste using a low-temperature glass frit as a binder is used. There is also a method in which when the filled conductive paste is in a semi-cured state, the metal sheet is directly pressure-bonded and thermally cured without using a conductive adhesive. In this case, the short circuit is also inspected in a semi-cured state.

Note that the conductive adhesive 66 does not necessarily have to be applied to the entire surface, and may be applied to the top of the filled conductive paste.
In addition, when the application area of the conductive paste or conductive adhesive is small, a semi-cured thermosetting resin sheet is used as the electric insulating layer to secure the adhesive strength between the electric insulating layer and the metal sheet. It may be crimped and thermally cured.

  In the method of the first embodiment described above, since the stylus 29 of the contact probe 28 directly touches the element 7C, the position of the element 7C may be displaced, poor contact with the support 10 or dropout may occur. In the method of the present embodiment, the element 7C is firmly supported by the support 10 by the electrical insulating layer 61, and the possibility that the element 7C is displaced or dropped in the inspection process can be reduced. On the other hand, since a step of covering the conductive paste 63 with the insulator 64 is necessary for the element having a short circuit, the manufacturing process is slightly complicated.

  In the method of the present embodiment, the short circuit is inspected in a state where the hole provided in the electrical insulating layer is filled with the conductive paste. However, the short circuit may be inspected before the conductive paste is filled. . In this case, with respect to the element that is short-circuited between the electrode and the support, the hole provided in the electrical insulating layer is filled with an insulator, and then the electrode of each element is made conductive as in the third embodiment. It applies so that it may connect with a paste, or it adhere | attaches a metal sheet to an electric insulation layer through a conductive adhesive.

(Embodiment 4)
The present embodiment is the same as the third embodiment in that a short circuit is inspected after a hole formed in the electrical insulating layer is filled with a conductive paste, but the formation of the first semiconductor electrode is different from that in the electrical insulating layer. This is different in that it is performed after a hole is made. Hereinafter, each step will be described focusing on differences from the third embodiment.

1) Step of preparing a structure in which a photoelectric conversion element is mounted in a concave portion of a support (1)
In this step, a. Preparing a photoelectric conversion element; b. Providing a support; and c. A structure in which the photoelectric conversion element is mounted in the concave portion of the support is prepared by each step of mounting the photoelectric conversion element on the support.

1-a) Step of Preparing Photoelectric Conversion Element In this step, a substantially spherical photoelectric conversion element is prepared by the same method as described in the step (1-a) of Embodiment 1.

1-b) Step of preparing support In this step, a support having a large number of recesses is prepared by the same method as described in step (1-c) of the first embodiment.

1-c) Step of mounting the photoelectric conversion element on the support In this step, the photoelectric conversion element is mounted on the support by the same method as described in the step (1-g) of the first embodiment.

2) Step of removing a part of the first semiconductor by removing the second semiconductor layer of the photoelectric conversion element exposed on the back side from the hole of the support (2)
In this step, the second semiconductor layer of the photoelectric conversion element exposed on the back surface side is removed from the hole of the support by the same method as described in the step (1-h) of the first embodiment, and the first semiconductor is removed. To expose a part of

3) Step of forming an electrical insulating layer on the back side of the support (3)
In this step, an electrical insulating layer is formed on the back side of the support 10 by the same method as in step (3) of the first embodiment. FIG. 16A shows a cross section of the support 10 in which the electrical insulating layer 67 is formed on the back surface side.

4) A step of opening a hole in the electrical insulating layer to expose a part of the first semiconductor of the photoelectric conversion element in the hole (4)
In this step, a hole for exposing the first semiconductor of the element is formed in the electrical insulating layer.

  Since this step is the same as the method described in step (4) of the first embodiment except that holes are formed in the electrical insulating layer for all elements mounted on the support, detailed description thereof is omitted. . FIG. 16B shows a state in which an electrical insulating layer 67 is formed on the back side of the support 10 and a hole 68 is formed in the electrical insulating layer 67 for exposing the first semiconductor 1 of the spherical element 7D. .

5) Step of filling the hole formed in the electrical insulating layer with the conductive paste and then performing heat treatment to form the electrode (5)
In this step, the conductive paste is filled in the hole 68 of the electrical insulating layer formed in the step (4), and then heat treatment is performed to form an electrode.

  First, the conductive paste 69 is applied to the surface of the first semiconductor 1 exposed in the hole 68 by filling the hole 68 of the electrical insulating layer with the conductive paste. Since the method of filling the conductive paste is the same as the method described in the step (5) of Embodiment 2, detailed description thereof is omitted. Note that it is preferable to use a glass frit-type conductive paste that can withstand a subsequent heat treatment as the conductive paste. FIG. 16 (3) shows a state in which the hole 68 is filled with the conductive paste 69.

  Next, the conductive paste 69 filled in the holes is irradiated with a laser and locally heated to form electrodes. The laser irradiation can be performed, for example, using a YAG laser device at a scanning speed of 1000 mm / sec and a printing pulse cycle of 10 μm. By this step, the conductive paste 69 is changed to the electrode 69A as shown in FIG. 16 (4).

6) Inspecting the presence or absence of a short circuit between the electrode formed on the first semiconductor and the support (6)
In this step, whether there is a short circuit between the electrode 69 formed on the first semiconductor 1 of the element 7E on which the electrode 69A is formed and the support 10 is determined by the same method as in step (5) of the third embodiment. inspect.

  The short circuit between the electrode 69 </ b> A and the support 10 is caused by the misalignment between the hole 68 formed in the electrical insulating layer 67 and the hole of the support 10, and the end of the hole of the support 10 or the conductive adhesive 13 is formed in the hole 68. Occurs when exposed inside.

7) Step (7) of covering the electrode of the photoelectric conversion element that has a short circuit between the electrode and the support in the step (6) with an insulator.
In this step, the shorted electrode 69 is covered with an insulator in the same manner as in step (6) of the third embodiment.

8) Step of electrically connecting each electrode of the first semiconductor of the plurality of photoelectric conversion elements (8)
In this step, the electrodes 69A of the element 7E are electrically connected in parallel by the same method as in the step (7) of the third embodiment, except for the element that has been short-circuited in the inspection step (6).

(Embodiment 5)
In this embodiment, a step (1) of preparing a structure in which a photoelectric conversion element is mounted in a concave portion of a support, and the presence or absence of a short circuit between the electrode formed on the first semiconductor and the support are inspected. The steps after step (6) are the same as those in the fourth embodiment, and the step of forming electrodes on the first semiconductor of the element is different from that in the fourth embodiment. Hereinafter, steps (2) to (5) different from the fourth embodiment will be described.

1) Step of forming an electrical insulating layer on the back side of the support (2)
In this step, an electrical insulating layer is formed on the back side of the support by the same method as in step (3) of the first embodiment. FIG. 17 (1) shows a cross section of the support 10 in which the electrical insulating layer 70 is formed on the back surface side.

2) A step of opening a hole in the electrical insulating layer to expose a part of the second semiconductor layer of the photoelectric conversion element in the hole (3)
In this step, a hole for exposing the second semiconductor layer 2 of the element 7 </ b> A is formed in the electrical insulating layer 70. Since this step is the same as the method described in step (4) of the first embodiment except that holes are formed in the electrical insulating layer for all elements mounted on the support, detailed description thereof is omitted. . FIG. 17B shows a state where a hole 71 for exposing the second semiconductor layer 2 of the spherical element 7 </ b> A is formed in the electrical insulating layer 70 formed on the back surface side of the support 10.

  If the hole 71 is too large, the contact area with the element 7A is reduced, the strength for supporting the element 7A is reduced, the conductive adhesive 13 is exposed in the hole 71, and a short circuit occurs later when an electrode is formed. Cause. On the other hand, if the hole 71 is too small, it causes the second semiconductor layer 2 and the electrode to contact each other during electrode formation. For this reason, it is necessary to determine the size of the hole 71 in consideration of these conditions.

3) Step (4) of removing a part of the first semiconductor by removing the second semiconductor layer of the photoelectric conversion element exposed in the hole
In this step, a part of the first semiconductor is exposed by removing the second semiconductor layer 2 of the photoelectric conversion element 7A exposed in the hole 71 by etching. The electrical insulating layer 70 is used as a resist film, and a mixed solution of hydrofluoric acid and nitric acid is used as an etchant. After the etching is completed, it is washed with water and dried. FIG. 17C shows a cross section of the spherical element 7 </ b> F in which the first semiconductor 1 is exposed in the hole 71.

4) Step of forming an electrode by applying a conductive paste to the surface of the first semiconductor exposed in the hole and then performing heat treatment (5)
In this step, an electrode is formed on the surface of the first semiconductor by the same method as in step (1-i) of the first embodiment. FIG. 17 (4) shows a state where the conductive paste 72 is applied to the surface of the first semiconductor 1 exposed in the hole 71.

  The method for manufacturing a photoelectric conversion device according to the present invention is particularly useful for manufacturing a solar cell.

It is a longitudinal cross-sectional view which shows the process of producing the photoelectric conversion element which has an electrode in the exposed part of the 1st semiconductor in Embodiment 1 of this invention. It is a bottom view of the photoelectric conversion element which has an electrode in the exposed part of the 1st semiconductor in the same Embodiment 1. It is a top view of the support body in the same Embodiment 1. It is the IV-IV sectional view taken on the line of FIG. It is a longitudinal cross-sectional view of the support body printed with the conductive adhesive in the first embodiment. It is sectional drawing which shows the state which mounted | wore the support body in the same Embodiment 1 with the photoelectric conversion element. It is a longitudinal cross-sectional view which shows the process of forming an electrode in the photoelectric conversion element with which the support body in the same Embodiment 1 was mounted | worn. It is a top view which shows the state which mounted | wore the support body in the same Embodiment 1 with the photoelectric conversion element. It is the VV sectional view taken on the line of FIG. It is a block diagram of the mounting inspection system used for the first embodiment. FIG. 6 is a longitudinal sectional view showing a step of forming an electrical insulating layer on the back surface of the support in the first embodiment. FIG. 6 is a longitudinal sectional view showing a conductive paste application step in the first embodiment. It is a top view which shows the application | coating pattern of the electrically conductive paste apply | coated at the process of FIG. It is a longitudinal cross-sectional view which shows the first half of the process of joining the composite sheet of an electrically insulating layer and an electroconductive metal sheet to the back surface of a support body in Embodiment 2 of this invention. It is a longitudinal cross-sectional view which shows the second half of the process of joining the composite sheet of an electrically insulating layer and a conductive metal sheet to the back surface of the support in Embodiment 2. It is a longitudinal cross-sectional view which shows each manufacturing process in Embodiment 3 of this invention. It is a longitudinal cross-sectional view which shows each manufacturing process in Embodiment 4 of this invention. It is a longitudinal cross-sectional view which shows each manufacturing process in Embodiment 5 of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 1st semiconductor 2 2nd semiconductor layer 3 Opening part of 2nd semiconductor layer 4 Exposed part of 1st semiconductor 5, 69A Electrode 7A-7G Photoelectric conversion element 10 Support body 11 Recessed part 12 Hole 13, 66 Conductive adhesive agent 14, 56, 63, 69, 72 Conductive paste 20 Short-circuit inspection device 21 Constant voltage device 22 Current measurement device 23 Information processing device 25 Stage 27 Electric cylinder 28 Contact probe 29 Contact needle 30 Driver 31 Sequencer 32 Relay 33 Memory 41, 48 Nozzle 44 , 54, 61, 67, 70 Electrical insulation layer 46 Laser irradiation device 47, 55, 62, 68, 71 Hole 50 Conductive paste coating layer 51 Adhesive layer 53, 65 Conductive metal sheet 64 Insulator

Claims (20)

(1) It comprises a spherical first semiconductor and a second semiconductor layer covering the surface thereof, the second semiconductor layer has an opening for exposing a part of the first semiconductor, and the first semiconductor is exposed. A plurality of substantially spherical photoelectric conversion elements each having an electrode formed thereon, and a plurality of adjacent recesses, and the recess is formed of a conductive support having a hole smaller than the photoelectric conversion element at the bottom;
The photoelectric conversion element is mounted in each recess of the support so that the exposed portion of the first semiconductor faces the back side of the support from the hole, and the second semiconductor layer of the photoelectric conversion element is supported by the support Preparing a structure electrically connected to the body,
(2) A step of inspecting the presence or absence of a short circuit between the electrode of the first semiconductor of the photoelectric conversion element mounted on the support and the support,
(3) forming an electrical insulating layer on the back side of the support;
(4) In the step (2), a hole is formed in the electrical insulating layer to expose the electrode in the hole for the photoelectric conversion element that is not short-circuited between the electrode of the first semiconductor and the support. And (5) a method of manufacturing a photoelectric conversion device, comprising: (5) electrically connecting the electrodes of the first semiconductors of the plurality of photoelectric conversion elements mounted on the support.   In the step (5), the hole of the electrical insulation layer is filled with a conductive paste, and the conductive paste is applied to the surface of the electrode exposed in the hole, and the electrical insulation is performed so as to connect the conductive paste. The manufacturing method of the photoelectric conversion apparatus of Claim 1 including the process of apply | coating an electrically conductive paste on a layer and heating and solidifying.   In the step (5), a conductive paste is applied to the surface of the electrode exposed in the hole by filling the hole in the electric insulating layer with the conductive paste, and then a conductive metal sheet is bonded to the electric insulating layer. And the manufacturing method of the photoelectric conversion apparatus of Claim 1 including the process of heating and solidifying the said conductive paste and electrically connecting the said conductive paste and the said conductive metal sheet. (1) It comprises a spherical first semiconductor and a second semiconductor layer covering the surface thereof, the second semiconductor layer has an opening for exposing a part of the first semiconductor, and the first semiconductor is exposed. A plurality of substantially spherical photoelectric conversion elements each having an electrode formed thereon, and a plurality of adjacent recesses, and the recess is formed of a conductive support having a hole smaller than the photoelectric conversion element at the bottom;
The photoelectric conversion element is mounted in each recess of the support so that the exposed portion of the first semiconductor faces the back side of the support from the hole, and the second semiconductor layer of the photoelectric conversion element is supported by the support Preparing a structure electrically connected to the body,
(2) A step of inspecting the presence or absence of a short circuit between the electrode of the first semiconductor of the photoelectric conversion element mounted on the support and the support,
(3) The process of joining the electrically insulating layer which isolates a conductive metal sheet and the said conductive metal sheet, and the said support body to the back surface side of the said support body,
(4) In the step (2), for the photoelectric conversion element that is not short-circuited between the electrode of the first semiconductor and the support, the photoelectric conversion is performed by opening a hole in the electrical insulating layer and the conductive metal sheet. A step of exposing the electrode of the element in the hole; and (5) filling the hole of the electrical insulating layer and the conductive metal sheet with a conductive paste and applying the conductive paste to the surface of the electrode exposed in the hole. And the manufacturing method of the photoelectric conversion apparatus including the process of electrically connecting each electrode of the 1st semiconductor of these photoelectric conversion elements, and the said electroconductive metal sheet.   In the step (3), a composite sheet in which an electrical insulation layer is joined to one side of a conductive metal sheet is integrated on the back side of the support, and the electrical insulation layer is joined to the support. The manufacturing method of the photoelectric conversion apparatus of Claim 4 including a process.   In the step (1), the photoelectric conversion element is fixed via a conductive adhesive applied to the peripheral edge of the hole of the concave portion of the support, and the second semiconductor layer and the support are electrically connected. The manufacturing method of the photoelectric conversion apparatus of Claim 1 or 4 currently performed.   For each photoelectric conversion element mounted on the support, data relating to the inspection result in the step (2) and data relating to the position of the concave portion of the support are stored in a memory. In the step (4), the data is stored in the memory. 5. The photoelectric conversion device according to claim 1, wherein the stored data is read out, and whether to make a hole in the electrical insulating layer or the electrical insulating layer and the conductive sheet is determined based on the data. Method.   In the step (2), a stylus is brought into contact with the electrode of the photoelectric conversion element from the back side of the support, and the presence or absence of a short circuit is inspected by measuring a current flowing between the stylus and the support. The manufacturing method of the photoelectric conversion apparatus of Claim 1 or 4.   Instead of the step (2), a camera is used to photograph the mounting state of the photoelectric conversion element mounted on the support, and the first semiconductor electrode and the peripheral portion of the support or the peripheral portion are connected. The manufacturing method of the photoelectric conversion apparatus of Claim 6 which test | inspects the presence or absence of a contact with a conductive adhesive. (1) It comprises a spherical first semiconductor and a second semiconductor layer covering the surface thereof, the second semiconductor layer has an opening for exposing a part of the first semiconductor, and the first semiconductor is exposed. A plurality of substantially spherical photoelectric conversion elements each having an electrode formed thereon, and a plurality of adjacent recesses, and the recess is formed of a conductive support having a hole smaller than the photoelectric conversion element at the bottom;
The photoelectric conversion element is mounted in each recess of the support so that the exposed portion of the first semiconductor faces the back side of the support from the hole, and the second semiconductor layer of the photoelectric conversion element is supported by the support Preparing a structure electrically connected to the body,
(2) forming an electrical insulating layer on the back side of the support;
(3) A step of opening a hole in the electrical insulating layer to expose a first semiconductor electrode of the photoelectric conversion element in the hole;
(4) A step of filling the hole of the electrical insulating layer with a conductive paste and applying the conductive paste to the surface of the electrode exposed in the hole;
(5) A step of inspecting for the presence or absence of a short circuit between the conductive paste filled in the holes of the electrical insulating layer and the support,
(6) In the step (5), the conductive paste filled in the hole of the electrical insulating layer is made of an insulator with respect to the photoelectric conversion element short-circuited between the conductive paste and the support. A method of manufacturing a photoelectric conversion device, comprising: a step of covering; and (7) a step of electrically connecting each electrode of the plurality of photoelectric conversion elements through a conductive paste filled in a hole of the electrical insulating layer.   The said process (7) includes the process of apply | coating a conductive paste on the said electrical insulating layer so that the conductive paste with which the hole of the said electrical insulating layer was filled may be connected, and solidifying by heating. Method for manufacturing a photoelectric conversion device.   The step (7) includes a step of electrically connecting the conductive paste and the conductive metal sheet by heating and solidifying the conductive paste after joining the conductive metal sheet to the electrical insulating layer. Item 11. A method for manufacturing a photoelectric conversion device according to Item 10.   For each photoelectric conversion element mounted on the support, data relating to the inspection result in the step (5) and data relating to the position of the concave portion of the support are stored in a memory. In the step (6), the data is stored in the memory. The method for manufacturing a photoelectric conversion device according to claim 10, wherein the stored data is read out and whether or not the conductive paste filled in the holes of the electrical insulating layer is covered with an insulator is determined based on the data.   In the step (5), the stylus is brought into contact with the conductive paste filled in the hole of the electrical insulating layer from the back side of the support, and the current flowing between the stylus and the support is measured. The manufacturing method of the photoelectric conversion apparatus of Claim 10 which test | inspects the presence or absence of a short circuit by. (1) A plurality of substantially spherical photoelectric conversion elements comprising a spherical first semiconductor and a second semiconductor layer covering the surface thereof, and a plurality of adjacent recesses, and a hole smaller than the photoelectric conversion element at the bottom. Consists of a conductive support,
Preparing a structure in which the photoelectric conversion element is mounted in each recess of the support and the second semiconductor layer of the photoelectric conversion element is electrically connected to the support;
(2) removing the second semiconductor layer of the photoelectric conversion element exposed to the back side from the hole of the support to expose a part of the first semiconductor;
(3) forming an electrical insulating layer on the back side of the support;
(4) A step of opening a hole in the electrical insulating layer to expose a part of the first semiconductor of the photoelectric conversion element in the hole;
(5) Filling the hole of the electrical insulating layer with a conductive paste and applying the conductive paste to the surface of the first semiconductor exposed in the hole, followed by heat treatment to form an electrode;
(6) A step of inspecting the presence or absence of a short circuit between the electrode formed on the first semiconductor and the support,
(7) The step of covering the electrode with an insulator for the photoelectric conversion element short-circuited between the electrode and the support in the step (6), and (8) The electrode in the step (7). The manufacturing method of a photoelectric conversion apparatus including the process of electrically connecting each electrode of the 1st semiconductor of these photoelectric conversion elements except the photoelectric conversion element covered with the insulator. (1) A plurality of substantially spherical photoelectric conversion elements comprising a spherical first semiconductor and a second semiconductor layer covering the surface thereof, and a plurality of adjacent recesses, and a hole smaller than the photoelectric conversion element at the bottom. Consists of a conductive support,
Preparing a structure in which the photoelectric conversion element is mounted in each recess of the support and the second semiconductor layer of the photoelectric conversion element is electrically connected to the support;
(2) forming an electrical insulating layer on the back side of the support;
(3) A step of opening a hole in the electrical insulating layer to expose a part of the second semiconductor layer of the photoelectric conversion element in the hole;
(4) removing the second semiconductor layer of the photoelectric conversion element exposed in the hole of the electrical insulating layer to expose a part of the first semiconductor;
(5) A step of applying a conductive paste to the surface of the first semiconductor exposed in the hole of the electrical insulating layer, and then performing a heat treatment to form an electrode;
(6) A step of inspecting the presence or absence of a short circuit between the electrode formed on the first semiconductor and the support,
(7) The step of covering the electrode with an insulator with respect to the photoelectric conversion element short-circuited between the electrode of the first semiconductor and the support in the step (6), and (8) the step (7 The manufacturing method of the photoelectric conversion apparatus including the process of electrically connecting each electrode of the 1st semiconductor of a said some photoelectric conversion element except the photoelectric conversion element which covered the electrode with the insulator in).   The step (8) includes a step of applying a conductive paste on the electrical insulating layer so as to connect the electrodes of the first semiconductor of the photoelectric conversion element, and heating and solidifying the conductive paste. A method for manufacturing a photoelectric conversion device.   The step (8) includes a step of electrically connecting a first metal electrode of the photoelectric conversion element and the conductive metal sheet after bonding a conductive metal sheet to the electrical insulating layer. A method for producing the photoelectric conversion device according to 16.   For each photoelectric conversion element mounted on the support, data relating to the inspection result in the step (6) and data relating to the position of the concave portion of the support are stored in a memory. In the step (7), the data is stored in the memory. 17. The method of manufacturing a photoelectric conversion device according to claim 15, wherein the stored data is read and whether or not the electrode formed on the first semiconductor is covered with an insulator is determined based on the data. In step (6), a stylus is brought into contact with the electrode formed on the first semiconductor from the back side of the support, and a current flowing between the stylus and the support is measured to determine whether or not there is a short circuit. The manufacturing method of the photoelectric conversion apparatus of Claim 15 or 16 which inspects.

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