JP7051746B2 - Manufacturing method of optical equipment - Google Patents

Description

One aspect of the present invention relates to a method for removing foreign matter adhering to a Fabry-Perot interference filter and a method for manufacturing a light detection device.

As a conventional Fabry-Perot interference filter, a substrate and a fixed mirror and a movable mirror facing each other via a gap on the substrate are known (see, for example, Patent Document 1).

Japanese Patent Publication No. 2013-506154

Since the Fabric Perry interference filter has a membrane-like and relatively fragile movable mirror, there is basically no attempt to remove foreign matter by a method in which there is a concern that the movable mirror may be deformed or damaged. For this reason, the Fabry-Perot interference filter in which foreign matter only adheres to the surface may be treated as a defective product, which hinders the improvement of the yield.

Therefore, one aspect of the present invention is to provide a foreign matter removing method capable of effectively removing foreign matter adhering to the Fabry-Perot interference filter and improving the yield, and a method of manufacturing a light detection device. The purpose.

The method for removing foreign matter according to one aspect of the present invention includes a substrate having a first surface and a second surface facing each other, a first laminated body having a first mirror portion arranged on the first surface, and a first mirror portion. A Fabry-Perot interference filter comprising a second laminated body having a second mirror portion arranged above, the portion of the first laminated body facing each other including at least the first mirror portion, and at least the second laminated body. Fabry-Perot interference configured so that the distance between the first mirror portion and the second mirror portion facing each other changes due to electrostatic force by forming a gap between the portion including the second mirror portion. The step of preparing a filter, the step of detecting foreign matter adhering to the surface of the second laminated body opposite to the first laminated body, and the air whose position of the airflow peak is adjusted based on the position of the detected foreign matter. Includes a step of removing foreign matter from the surface of the second laminated body by spraying the above on the surface of the second laminated body.

According to the foreign matter removing method according to one aspect of the present invention, the foreign matter adhering to the surface of the second laminated body of the Fabry-Perot interference filter can be detected and the foreign matter can be removed by blowing air. Since the position of the air flow peak of the air is adjusted based on the position of the detected foreign matter, the foreign matter can be appropriately removed by blowing the air. As described above, according to the above-mentioned foreign matter removing method, the foreign matter adhering to the Fabry-Perot interference filter can be effectively removed, and the Fabry-Perot interference filter can be obtained with a good yield.

Here, in the Fabry-Perot interference filter, a gap is formed between a portion of the first laminated body including at least the first mirror portion and a portion of the second laminated body including at least the second mirror portion. That is, the portion of the second laminated body that overlaps the void when viewed from the direction in which the first mirror portion and the second mirror portion face each other (hereinafter, simply referred to as “membrane portion”) has a so-called membrane structure. It is a relatively vulnerable part. For this reason, conventionally, no attempt has been made to remove foreign matter by a method in which a stress that is a load is generated on the membrane portion and there is a concern that the membrane portion may be deformed or damaged. It was often treated as. However, as a result of diligent research by the present inventors, the method of blowing air does not significantly affect the characteristics of the Fabry-Perot interference filter, even though it is a method of generating stress in the membrane portion, and foreign matter is not affected. It was confirmed that it is possible to remove.

In the step of removing the foreign matter, the position of the airflow peak may be adjusted to match the position of the foreign matter. In this case, the airflow peak (that is, the portion where the air flow velocity is the largest) directly hits the foreign matter, so that the foreign matter can be removed more reliably.

In the portion of the second laminated body where the first mirror portion and the second mirror portion overlap with the voids when viewed from the opposite directions, a plurality of through holes extending from the surface of the second laminated body to the voids are formed. In the step of removing foreign matter, air may be blown to at least a region of the surface of the second laminated body in which a plurality of through holes are formed. In this case, the air blown onto the surface of the second laminated body can be allowed to enter the voids through the plurality of through holes. The air that has entered the void is pushed out by the air that newly enters the void, and the second through hole is different from the through hole through which the air that newly enters the void flows. It is discharged to the surface side of the laminate. The air discharged to the outside from the voids in this way can blow up the foreign matter adhering to the surface of the second laminated body. This makes it possible to more effectively remove foreign matter adhering to the Fabry-Perot interference filter.

In the process of preparing the Fabry-Pérot interference filter, a wafer in which a plurality of Fabry-Pérot interference filters are connected in two dimensions is prepared, and in the process of detecting foreign matter and the step of removing foreign matter, the Fabry-Pérot interference filter constituting the wafer is prepared. May be implemented against. In this case, when foreign matter adheres to the Fabry-Perot interference filter constituting the wafer, the foreign matter can be removed by blowing air. As a result, when inspecting each of the plurality of Fabry-Pérot interference filters that make up the wafer, the Fabry-Pérot interference filter to which foreign matter has adhered is not immediately determined to be defective, and the Fabry-Pérot interference filter from which foreign matter has been removed is regarded as a good product. It can be sent to a later process. Therefore, the yield of the Fabry-Perot interference filter can be improved.

In the step of preparing the Fabry-Perot interference filter, an individualized Fabry-Pérot interference filter may be prepared. For example, when foreign matter is removed by blowing air on a Fabry-Pérot interference filter that constitutes a wafer containing a plurality of Fabry-Pérot interference filters, the foreign matter is scattered on other Fabry-Pérot interference filters that make up the wafer. , May adversely affect the other Fabry-Perot interference filters. On the other hand, at the stage where the Fabry-Pérot interference filter is separated as described above, foreign matter is removed by blowing air onto the Fabry-Pérot interference filter to obtain other Fabry-Pérot interference filters as described above. It is possible to prevent the occurrence of adverse effects.

A method for manufacturing a light detection device according to one aspect of the present invention includes a package having a cap having an opening for incident light and a stem joined to the cap, a Fabry-Perot interference filter arranged in the package, and a package. A method of manufacturing an optical detection device comprising an optical detector arranged inside to detect light transmitted through a Fabry-Pérot interference filter, wherein the Fabry-Pérot interference filter has a first surface and a second surface facing each other. A substrate having a substrate, a first laminated body having a first mirror portion arranged on a first surface, and a second laminated body having a second mirror portion arranged on the first mirror portion are provided and face each other. By forming a gap between the portion including at least the first mirror portion of the first laminated body and the portion including at least the second mirror portion of the second laminated body, the first mirror portion and the second mirror facing each other are formed. It is a Fabry-Perot interference filter configured so that the distance between the parts is changed by electrostatic force. The step of detecting foreign matter adhering to the surface of the second laminated body of the Fabry-Pérot interference filter fixed in place on the opposite side of the first laminated body, and the position of the airflow peak are adjusted based on the position of the detected foreign matter. It includes a step of removing foreign matter from the surface of the second laminated body by blowing the air on the surface of the second laminated body, and a step of joining a cap to the stem after the step of removing the foreign matter.

According to the manufacturing method of this optical detection device, in a state where the Fabry-Perot interference filter and the optical detector are fixed to the stem, foreign matter adhering to the surface of the second laminate of the Fabry-Perot interference filter is detected and air is detected. The foreign matter can be removed by spraying. That is, it is possible to appropriately detect and remove foreign matter adhering to the Fabry-Perot interference filter in the state immediately before the photodetector is obtained. Here, since the assembly work of the photodetector is not always performed in a clean room with high cleanliness, the possibility that foreign matter adheres to the surface of the Fabry-Perot interference filter during the assembly work may be relatively high. There is sex. According to the above manufacturing method, in the final stage of the manufacturing process of the optical detection device, foreign matter adhering to the Fabry-Perot interference filter can be removed without significantly affecting the characteristics of the Fabry-Perot interference filter. As a result, the non-defective rate of the photodetector, which is the final product, can be improved, and the photodetector can be obtained with a good yield.

A method for manufacturing a light detection device according to another aspect of the present invention includes a package having a lid substrate and a support bonded to the lid substrate, a Fabry-Perot interference filter arranged in the package, and a Fabry-Perot interference filter arranged in the package. A method of manufacturing an optical detection device including a light detector for detecting light transmitted through a Fabry-Perot interference filter, wherein the Fabry-Pérot interference filter includes a substrate having a first surface and a second surface facing each other, and a first surface. A first laminated body having a first mirror portion arranged on one surface and a second laminated body having a second mirror portion arranged on the first mirror portion, and facing each other. By forming a gap between the portion including at least the first mirror portion and the portion including at least the second mirror portion of the second laminated body, the space between the first mirror portion and the second mirror portion facing each other is formed. It is a Fabry-Perot interference filter configured so that the distance changes due to electrostatic force, and the manufacturing method corresponds to a plurality of Fabry-Perot interference filters arranged in one or two dimensions and a plurality of Fabry-Perot interference filters. A step of preparing a plurality of provided optical detectors, a support layer for supporting a plurality of Fabry-Perot interference filters and a plurality of optical detectors, and a support layer to be cut into a plurality of supports. For each of the plurality of Fabry-Perot interference filters, the step of detecting foreign matter adhering to the surface of the second laminated body opposite to the first laminated body and the position of the airflow peak based on the position of the detected foreign matter are determined. A lid to be cut into the plurality of lid substrates after a step of removing foreign matter from the surface of the second laminated body and a step of removing foreign matter by blowing the adjusted air on the surface of the second laminated body. By joining the substrate layer to the support layer, a process of obtaining a plurality of one-dimensional or two-dimensionally connected light detection devices, and by cutting the portion where the lid substrate layer and the support layer are joined, individual light detectors are obtained. Includes a step of obtaining a light detector.

According to the manufacturing method of this optical detection device, in a state where a plurality of Fabry-Perot interference filters are supported by a support layer, foreign matter adhering to the surface of the second laminate of each Fabry-Perot interference filter is detected and air is blown. Can remove the foreign matter. That is, it is possible to appropriately detect and remove foreign matter adhering to each Fabry-Perot interference filter in the state immediately before the photodetector is obtained. Therefore, according to this manufacturing method, the same effect as the manufacturing method of the photodetector described above can be obtained.

In the process of obtaining a plurality of photodetectors, a lid substrate layer having a plurality of openings previously formed is bonded to a support layer so that each of the plurality of openings faces each of the plurality of Fabry-Perot interference filters. May be good. In this case, by using the lid substrate layer in which a plurality of openings are formed in advance, a photodetector having openings formed in the lid substrate for light incident can be obtained immediately after cutting the lid substrate layer and the support layer. Can be done. This eliminates the need for a step of forming an opening in the lid substrate of each photodetector after cutting.

According to one aspect of the present invention, it is possible to provide a foreign matter removing method capable of effectively removing foreign matter adhering to the Fabry-Perot interference filter and improving the yield, and a method for manufacturing a light detection device. can.

It is a top view of the Fabry-Perot interference filter cut out from the wafer of one Embodiment. It is a bottom view of the Fabry-Perot interference filter shown in FIG. It is sectional drawing of the Fabry-Perot interference filter along the line III-III shown in FIG. It is sectional drawing of the dummy filter cut out from the wafer of one Embodiment. It is a top view of the wafer of one Embodiment. FIG. 5 is an enlarged plan view of a part of the wafer shown in FIG. It is sectional drawing of the Fabry-Perot interference filter part and the dummy filter part of the wafer shown in FIG. It is sectional drawing for demonstrating the manufacturing method of the wafer shown in FIG. It is sectional drawing for demonstrating the manufacturing method of the wafer shown in FIG. It is sectional drawing for demonstrating the manufacturing method of the wafer shown in FIG. It is sectional drawing for demonstrating the manufacturing method of the wafer shown in FIG. It is sectional drawing for demonstrating the manufacturing method of the wafer shown in FIG. It is sectional drawing for demonstrating the manufacturing method of the wafer shown in FIG. It is a schematic block diagram of the foreign matter removing apparatus in which the foreign matter removing method of one Embodiment is carried out. It is a graph which shows the comparison result before and after the air blow of the characteristic (peak transmission wavelength with respect to the filter control voltage) of a Fabry-Perot interference filter. It is a graph which shows the comparison result before and after the air blow of the characteristic (wavelength resolution with respect to the peak transmission wavelength) of a Fabry-Perot interference filter. It is sectional drawing for demonstrating the method of cutting out the Fabry-Perot interference filter from the wafer shown in FIG. It is sectional drawing for demonstrating the method of cutting out the Fabry-Perot interference filter from the wafer shown in FIG. It is sectional drawing of the photodetector of 1st Embodiment. It is sectional drawing for demonstrating the manufacturing method of the photodetector shown in FIG. It is sectional drawing of the photodetector of 2nd Embodiment. It is a top view of the photodetector shown in FIG. It is sectional drawing for demonstrating the manufacturing method of the photodetector shown in FIG. It is sectional drawing for demonstrating the manufacturing method of the photodetector shown in FIG.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In each figure, the same or corresponding parts are designated by the same reference numerals, and duplicate description will be omitted.
[Structure of Fabry-Perot Interference Filter and Dummy Filter]

Prior to the description of the method for removing foreign matter and the method for manufacturing the light detection device according to the embodiment, the configurations of the Fabry-Perot interference filter and the dummy filter cut out from the wafer will be described.

As shown in FIGS. 1, 2 and 3, the Fabry-Perot interference filter 1 includes a substrate 11. The substrate 11 has a first surface 11a and a second surface 11b facing each other. The antireflection layer 21, the first laminated body 22, the intermediate layer 23, and the second laminated body 24 are laminated in this order on the first surface 11a. A gap (air gap) S is defined between the first laminated body 22 and the second laminated body 24 by a frame-shaped intermediate layer 23.

The shape and positional relationship of each part when viewed from a direction perpendicular to the first surface 11a (planar view) are as follows. The outer edge of the substrate 11 is, for example, rectangular. The outer edge of the substrate 11 and the outer edge of the second laminated body 24 coincide with each other. The outer edge of the antireflection layer 21, the outer edge of the first laminated body 22, and the outer edge of the intermediate layer 23 coincide with each other. The substrate 11 has an outer edge portion 11c located outside the center of the gap S with respect to the outer edge of the intermediate layer 23. The outer edge portion 11c has, for example, a frame shape and surrounds the intermediate layer 23 when viewed from a direction perpendicular to the first surface 11a. The void S is, for example, circular.

The Fabry-Perot interference filter 1 transmits light having a predetermined wavelength in the light transmission region 1a defined in the central portion thereof. The light transmission region 1a is, for example, a columnar region. The substrate 11 is made of, for example, silicon, quartz, glass, or the like. When the substrate 11 is made of silicon, the antireflection layer 21 and the intermediate layer 23 are made of, for example, silicon oxide. The thickness of the intermediate layer 23 is, for example, several tens of nm to several tens of μm.

The portion of the first laminated body 22 corresponding to the light transmission region 1a functions as the first mirror portion 31. The first mirror unit 31 is a fixed mirror. The first mirror portion 31 is arranged on the first surface 11a via the antireflection layer 21. The first laminated body 22 is configured by alternately laminating a plurality of polysilicon layers 25 and a plurality of silicon nitride layers 26 one by one. In the Fabric Perot Interference Filter 1, the polysilicon layer 25a, the silicon nitride layer 26a, the polysilicon layer 25b, the silicon nitride layer 26b, and the polysilicon layer 25c are laminated on the antireflection layer 21 in this order. The optical thickness of each of the polysilicon layer 25 and the silicon nitride layer 26 constituting the first mirror portion 31 is preferably an integral multiple of 1/4 of the central transmission wavelength. The first mirror portion 31 may be arranged directly on the first surface 11a without interposing the antireflection layer 21.

The portion of the second laminated body 24 corresponding to the light transmission region 1a functions as the second mirror portion 32. The second mirror unit 32 is a movable mirror. The second mirror portion 32 faces the first mirror portion 31 with respect to the first mirror portion 31 on the opposite side of the substrate 11 via the gap S. The direction in which the first mirror portion 31 and the second mirror portion 32 face each other is parallel to the direction perpendicular to the first surface 11a. The second laminated body 24 is arranged on the first surface 11a via the antireflection layer 21, the first laminated body 22 and the intermediate layer 23. The second laminated body 24 is configured by alternately laminating a plurality of polysilicon layers 27 and a plurality of silicon nitride layers 28 one by one. In the Fabric Perot Interference Filter 1, the polysilicon layer 27a, the silicon nitride layer 28a, the polysilicon layer 27b, the silicon nitride layer 28b, and the polysilicon layer 27c are laminated on the intermediate layer 23 in this order. The optical thickness of each of the polysilicon layer 27 and the silicon nitride layer 28 constituting the second mirror portion 32 is preferably an integral multiple of 1/4 of the central transmission wavelength.

In the first laminated body 22 and the second laminated body 24, a silicon oxide layer may be used instead of the silicon nitride layer. Further, as the material of each layer constituting the first laminated body 22 and the second laminated body 24, titanium oxide, tantalum oxide, zirconium oxide, magnesium fluoride, aluminum oxide, calcium fluoride, silicon, germanium, zinc sulfide and the like are used. It may be used. Further, here, the surface of the first mirror portion 31 on the void S side (the surface of the polysilicon layer 25c) and the surface of the second mirror portion 32 on the void S side (the surface of the polysilicon layer 27a) are the voids S. Directly facing each other via. However, an electrode layer (which does not form a mirror), a protective layer, or the like may be formed on the surface of the first mirror portion 31 on the void S side and the surface of the second mirror portion 32 on the void S side. In this case, the first mirror portion 31 and the second mirror portion 32 face each other with the gap S interposed therebetween, with their layers interposed therebetween. In other words, even in such a case, the facing of the first mirror portion 31 and the second mirror portion 32 via the gap S can be realized.

A plurality of through holes 24b are formed in a portion of the second laminated body 24 corresponding to the void S (a portion overlapping the void S when viewed from a direction perpendicular to the first surface 11a). Each through hole 24b reaches the void S from the surface 24a on the side opposite to the intermediate layer 23 of the second laminated body 24. The plurality of through holes 24b are formed to such an extent that they do not substantially affect the function of the second mirror portion 32. The plurality of through holes 24b are used to remove a part of the intermediate layer 23 by etching to form a void S.

The second laminated body 24 further has a covering portion 33 and a peripheral portion 34 in addition to the second mirror portion 32. The second mirror portion 32, the covering portion 33, and the peripheral portion 34 have a part of the same laminated structure and are integrally formed so as to be continuous with each other. The covering portion 33 surrounds the second mirror portion 32 when viewed from a direction perpendicular to the first surface 11a. The covering portion 33 includes a surface 23a on the side opposite to the substrate 11 of the intermediate layer 23, a side surface 23b of the intermediate layer 23 (outer side surface, that is, a side surface opposite to the void S side), and a first laminated body 22. 22a and the side surface 21a of the antireflection layer 21 are covered with the first surface 11a. That is, the covering portion 33 covers the outer edge of the intermediate layer 23, the outer edge of the first laminated body 22, and the outer edge of the antireflection layer 21.

The peripheral edge portion 34 surrounds the covering portion 33 when viewed from a direction perpendicular to the first surface 11a. The peripheral edge portion 34 is located on the first surface 11a in the outer edge portion 11c. The outer edge of the peripheral edge portion 34 coincides with the outer edge of the substrate 11 when viewed from a direction perpendicular to the first surface 11a. The peripheral edge portion 34 is thinned along the outer edge of the outer edge portion 11c. That is, the portion of the peripheral edge portion 34 along the outer edge of the outer edge portion 11c is thinner than the portion of the peripheral edge portion 34 excluding the portion along the outer edge. In the Fabry-Perot interference filter 1, the peripheral portion 34 is thinned by removing a part of the polysilicon layer 27 and the silicon nitride layer 28 constituting the second laminated body 24. The peripheral edge portion 34 has a non-thinning portion 34a continuous with the covering portion 33 and a thinning portion 34b surrounding the non-thinning portion 34a. In the thinned portion 34b, the polysilicon layer 27 and the silicon nitride layer 28 other than the polysilicon layer 27a provided directly on the first surface 11a are removed.

The height from the first surface 11a to the surface 34c of the non-thinned portion 34a opposite to the substrate 11 is lower than the height from the first surface 11a to the surface 23a of the intermediate layer 23. The height from the first surface 11a to the surface 34c of the non-thinned portion 34a is, for example, 100 nm to 5000 nm. The height from the first surface 11a to the surface 23a of the intermediate layer 23 is, for example, 500 nm to 20000 nm. The width of the thinned portion 34b (distance between the outer edge of the non-thinned portion 34a and the outer edge of the outer edge portion 11c when viewed from the direction perpendicular to the first surface 11a) is 0.01 of the thickness of the substrate 11. More than double. The width of the thinned portion 34b is, for example, 5 μm to 400 μm. The thickness of the substrate 11 is, for example, 500 μm to 800 μm.

The first electrode 12 is formed on the first mirror portion 31 so as to surround the light transmission region 1a when viewed from a direction perpendicular to the first surface 11a. The first electrode 12 is formed by doping the polysilicon layer 25c with impurities to reduce the resistance. The first mirror portion 31 is formed with a second electrode 13 so as to include a light transmission region 1a when viewed from a direction perpendicular to the first surface 11a. The second electrode 13 is formed by doping the polysilicon layer 25c with impurities to reduce the resistance. When viewed from a direction perpendicular to the first surface 11a, the size of the second electrode 13 is preferably a size including the entire light transmitting region 1a, but is substantially the same as the size of the light transmitting region 1a. There may be.

A third electrode 14 is formed on the second mirror portion 32. The third electrode 14 faces the first electrode 12 and the second electrode 13 via the gap S. The third electrode 14 is formed by doping the polysilicon layer 27a with impurities to reduce the resistance.

The pair of terminals 15 are provided so as to face each other with the light transmission region 1a interposed therebetween. Each terminal 15 is arranged in a through hole from the surface 24a of the second laminated body 24 to the first laminated body 22. Each terminal 15 is electrically connected to the first electrode 12 via the wiring 12a. Each terminal 15 is formed of, for example, a metal film such as aluminum or an alloy thereof.

The pair of terminals 16 are provided so as to face each other with the light transmission region 1a interposed therebetween. Each terminal 16 is arranged in a through hole from the surface 24a of the second laminated body 24 to the first laminated body 22. Each terminal 16 is electrically connected to the second electrode 13 via the wiring 13a and is electrically connected to the third electrode 14 via the wiring 14a. The terminal 16 is formed of, for example, a metal film such as aluminum or an alloy thereof. The direction in which the pair of terminals 15 face each other and the direction in which the pair of terminals 16 face each other are orthogonal to each other (see FIG. 1).

A plurality of trenches 17 and 18 are provided on the surface 22b of the first laminated body 22. The trench 17 extends in an annular shape so as to surround the connection portion of the wiring 13a with the terminal 16. The trench 17 electrically insulates the first electrode 12 and the wiring 13a. The trench 18 extends in an annular shape along the inner edge of the first electrode 12. The trench 18 electrically insulates the first electrode 12 and the region inside the first electrode 12 (second electrode 13). The region in each of the trenches 17 and 18 may be an insulating material or a void.

A trench 19 is provided on the surface 24a of the second laminated body 24. The trench 19 extends in an annular shape so as to surround the terminal 15. The trench 19 electrically insulates the terminal 15 and the third electrode 14. The region in the trench 19 may be an insulating material or a void.

The antireflection layer 41, the third laminated body 42, the intermediate layer 43, and the fourth laminated body 44 are laminated in this order on the second surface 11b of the substrate 11. The antireflection layer 41 and the intermediate layer 43 have the same configurations as the antireflection layer 21 and the intermediate layer 23, respectively. The third laminated body 42 and the fourth laminated body 44 have a laminated structure symmetrical with the first laminated body 22 and the second laminated body 24 with respect to the substrate 11, respectively. The antireflection layer 41, the third laminated body 42, the intermediate layer 43, and the fourth laminated body 44 have a function of suppressing the warp of the substrate 11.

The third laminated body 42, the intermediate layer 43, and the fourth laminated body 44 are thinned along the outer edge of the outer edge portion 11c. That is, the portion of the third laminated body 42, the intermediate layer 43, and the fourth laminated body 44 along the outer edge of the outer edge portion 11c is the portion of the third laminated body 42, the intermediate layer 43, and the fourth laminated body 44 along the outer edge. It is thinner than the other parts except. In the Fabry-Perot interference filter 1, the third laminated body 42, the intermediate layer 43, and the fourth laminated body 44 overlap with the thinned portion 34b when viewed from the direction perpendicular to the first surface 11a, and the third laminated body 42. , The intermediate layer 43 and the fourth laminated body 44 are all removed, so that the thickness is reduced.

The third laminated body 42, the intermediate layer 43, and the fourth laminated body 44 are provided with an opening 40a so as to include a light transmitting region 1a when viewed from a direction perpendicular to the first surface 11a. The opening 40a has a diameter substantially the same as the size of the light transmitting region 1a. The opening 40a is open on the light emitting side. The bottom surface of the opening 40a reaches the antireflection layer 41.

A light-shielding layer 45 is formed on the surface of the fourth laminated body 44 on the light emitting side. The light-shielding layer 45 is made of, for example, aluminum or the like. A protective layer 46 is formed on the surface of the light-shielding layer 45 and the inner surface of the opening 40a. The protective layer 46 covers the outer edges of the third laminated body 42, the intermediate layer 43, the fourth laminated body 44, and the light-shielding layer 45, and also covers the antireflection layer 41 on the outer edge portion 11c. The protective layer 46 is made of, for example, aluminum oxide. By setting the thickness of the protective layer 46 to 1 to 100 nm (preferably about 30 nm), the optical influence of the protective layer 46 can be ignored.

In the Fabry-Perot interference filter 1 configured as described above, when a voltage is applied between the first electrode 12 and the third electrode 14 via the pair of terminals 15 and 16, static electricity corresponding to the voltage is applied. A force is generated between the first electrode 12 and the third electrode 14. Due to the electrostatic force, the second mirror portion 32 is attracted to the side of the first mirror portion 31 fixed to the substrate 11, and the distance between the first mirror portion 31 and the second mirror portion 32 is adjusted. As described above, in the Fabry-Perot interference filter 1, the distance between the first mirror portion 31 and the second mirror portion 32 changes due to the electrostatic force.

The wavelength of light transmitted through the Fabry-Perot interference filter 1 depends on the distance between the first mirror unit 31 and the second mirror unit 32 in the light transmission region 1a. Therefore, by adjusting the voltage applied between the first electrode 12 and the third electrode 14, the wavelength of the transmitted light can be appropriately selected. At this time, the second electrode 13 has the same potential as the third electrode 14. Therefore, the second electrode 13 functions as a compensating electrode for keeping the first mirror portion 31 and the second mirror portion 32 flat in the light transmission region 1a.

In the Fabry-Pérot interference filter 1, for example, the distance applied to the Fabry-Pérot interference filter 1 is changed (that is, the distance between the first mirror unit 31 and the second mirror unit 32 in the Fabry-Pérot interference filter 1 is changed. However, a spectroscopic spectrum can be obtained by detecting the light transmitted through the light transmission region 1a of the Fabry-Perot interference filter 1 with a light detector.

As shown in FIG. 4, the dummy filter 2 has the above-mentioned Fabry-Perot in that a plurality of through holes 24b are not formed in the second laminated body 24 and no void S is formed in the intermediate layer 23. It is different from the interference filter 1. In the dummy filter 2, an intermediate layer 23 is provided between the first mirror portion 31 and the second mirror portion 32. That is, the second mirror portion 32 is not floating on the gap S and is arranged on the surface 23a of the intermediate layer 23.
[Wafer configuration]

Next, the configuration of the wafer of one embodiment will be described. As shown in FIGS. 5 and 6, the wafer 100 includes a substrate layer 110. The substrate layer 110 has, for example, a disk-like shape, and an orientation flat OF is formed in a part thereof. The substrate layer 110 is made of, for example, silicon, quartz, glass, or the like. Hereinafter, a virtual straight line that passes through the center of the substrate layer 110 and is parallel to the orientation flat OF when viewed from the thickness direction of the substrate layer 110 is referred to as a first straight line 3, and is referred to as a first straight line 3 when viewed from the thickness direction of the substrate layer 110. The virtual straight line passing through the center of the substrate layer 110 and perpendicular to the orientation flat OF is called the second straight line 4.

The wafer 100 is provided with an effective area 101 and a dummy area 102. The dummy area 102 is an area along the outer edge 110c of the substrate layer 110 (that is, the outer edge 100a of the wafer 100). The effective area 101 is an area inside the dummy area 102. The dummy area 102 surrounds the effective area 101 when viewed from the thickness direction of the substrate layer 110. The dummy area 102 is adjacent to the effective area 101.

The effective area 101 is provided with a plurality of Fabry-Perot interference filter units 1A arranged two-dimensionally. The plurality of Fabry-Perot interference filter units 1A are provided in the entire effective area 101. The dummy area 102 is provided with a plurality of dummy filter units 2A arranged two-dimensionally. The plurality of dummy filter units 2A are provided in an area of the dummy area 102 excluding the pair of areas 102a. One area 102a is an area along the orientation flat OF. The other area 102a is an area along the portion of the outer edge 110c of the substrate layer 110 opposite to the orientation flat OF. At the boundary between the effective area 101 and the dummy area 102, the Fabry-Perot interference filter unit 1A and the dummy filter unit 2A are adjacent to each other. When viewed from the thickness direction of the substrate layer 110, the outer shape of the Fabry-Perot interference filter unit 1A and the outer shape of the dummy filter unit 2A are the same. The plurality of Fabry-Perot interference filter units 1A and the plurality of dummy filter units 2A are arranged so as to be symmetrical with respect to each of the first straight line 3 and the second straight line 4 orthogonal to each other. The plurality of dummy filter units 2A may be provided in the entire dummy area 102. Further, the plurality of dummy filter units 2A may be provided in an area other than one of the dummy areas 102a.

The plurality of Fabry-Perot interference filter units 1A is a portion where the wafer 100 is cut along each line 5 to become a plurality of Fabry-Perot interference filters 1. The plurality of dummy filter units 2A are portions to be formed into a plurality of dummy filters 2 by cutting the wafer 100 along each line 5. When viewed from the thickness direction of the substrate layer 110, the plurality of lines 5 extend along the direction parallel to the orientation flat OF, and the plurality of lines 5 extend in the direction perpendicular to the orientation flat OF. It extends along the line. As an example, when the filter units 1A and 2A have a rectangular shape when viewed from the thickness direction of the substrate layer 110, the filter units 1A and 2A are arranged in a two-dimensional matrix, and the plurality of lines 5 are arranged. It is set in a grid pattern so as to pass between the adjacent filter units 1A and 1A, between the adjacent filter units 1A and 2A, and between the adjacent filter units 2A and 2A.

FIG. 7A is a cross-sectional view of the Fabry-Perot interference filter section 1A, and FIG. 7B is a cross-sectional view of the dummy filter section 2A. As shown in FIGS. 7A and 7B, the substrate layer 110 is a layer that is planned to become a plurality of substrates 11 by cutting the wafer 100 along each line 5. The substrate layer 110 has a first surface 110a and a second surface 110b facing each other. An antireflection layer 210 is provided on the first surface 110a of the substrate layer 110. The antireflection layer 210 is a layer to be formed into a plurality of antireflection layers 21 by cutting the wafer 100 along each line 5. An antireflection layer 410 is provided on the second surface 110b of the substrate layer 110. The antireflection layer 410 is a layer to be formed into a plurality of antireflection layers 41 by cutting the wafer 100 along each line 5.

A device layer 200 is provided on the antireflection layer 210. The device layer 200 includes a first mirror layer 220, an intermediate layer 230, and a second mirror layer 240. The first mirror layer 220 is a layer having a plurality of first mirror portions 31, and is a layer to be formed into a plurality of first laminated bodies 22 by cutting the wafer 100 along each line 5. .. The plurality of first mirror portions 31 are two-dimensionally arranged on the first surface 110a of the substrate layer 110 via the antireflection layer 210. The intermediate layer 230 is a layer to be formed into a plurality of intermediate layers 23 by cutting the wafer 100 along each line 5. The second mirror layer 240 is a layer having a plurality of second mirror portions 32, and is a layer to be formed into a plurality of second laminated bodies 24 by cutting the wafer 100 along each line 5. .. The plurality of second mirror portions 32 are two-dimensionally arranged on the first mirror layer 220 via the intermediate layer 23.

A stress adjusting layer 400 is provided on the antireflection layer 410. That is, the stress adjusting layer 400 is provided on the second surface 110b of the substrate layer 110 via the antireflection layer 410. The stress adjusting layer 400 has a plurality of layers 420, 430, 440. The layer 420 is a layer to be formed into a plurality of third laminated bodies 42 by cutting the wafer 100 along each line 5. The layer 430 is a layer to be formed into a plurality of intermediate layers 43 by cutting the wafer 100 along each line 5. The layer 440 is a layer to be formed into a plurality of fourth laminated bodies 44 by cutting the wafer 100 along each line 5.

A light-shielding layer 450 and a protective layer 460 are provided on the stress adjusting layer 400. The light-shielding layer 450 is a layer to be formed into a plurality of light-shielding layers 45 by cutting the wafer 100 along each line 5. The protective layer 460 is a layer to be formed into a plurality of protective layers 46 by cutting the wafer 100 along each line 5.

As shown in FIG. 7A, in each Fabry-Perot interference filter unit 1A, a portion including at least the first mirror portion 31 of the first mirror layer 220 facing each other and at least the second mirror of the second mirror layer 240. A gap S is formed between the portion including the portion 32 and the portion including the portion 32. That is, in each Fabry-Perot interference filter unit 1A, the intermediate layer 23 defines the void S, and the second mirror portion 32 floats on the void S. As shown in FIG. 1, in the present embodiment, when the first mirror unit 31 and the second mirror unit 32 are viewed from a direction facing each other (hereinafter, simply referred to as “opposite direction”), the void S is formed. It is formed in a circular region that is one size larger than the light transmission region 1a. Each Fabry-Perot interference filter unit 1A relates to a first electrode 12, a second electrode 13, a third electrode 14, a plurality of terminals 15, 16 and an opening 40a, as in the configuration of the Fabry-Perot interference filter 1 described above. The configuration is provided. Therefore, even if the plurality of Fabry-Perot interference filter units 1A remain in the state of the wafer 100, when a voltage is applied to each Fabry-Pérot interference filter unit 1A via the pair of terminals 15 and 16, the second Fabry-Perot interference filter unit 1A faces each other. The distance between the 1 mirror portion 31 and the 2nd mirror portion 32 changes due to the electrostatic force.

As shown in FIG. 7B, in each dummy filter unit 2A, an intermediate layer 23 is provided between the first mirror unit 31 and the second mirror unit 32 facing each other. That is, in the dummy filter portion 2A, the intermediate layer 23 does not define the void S, and the second mirror portion 32 is arranged on the surface 23a of the intermediate layer 23. Therefore, each dummy filter unit 2A has a configuration relating to the first electrode 12, the second electrode 13, the third electrode 14, the plurality of terminals 15, 16 and the opening 40a, as in the configuration of the dummy filter 2 described above. Although provided, the distance between the first mirror portion 31 and the second mirror portion 32 facing each other does not change. The dummy filter unit 2A has a first electrode 12, a second electrode 13, a third electrode 14, and a plurality of terminals 15, 16 (a metal film such as aluminum constituting each terminal 15, 16 and each terminal 15, It is not necessary to provide a structure related to a through hole or the like for arranging the 16), an opening 40a, or the like.

As shown in FIGS. 6 and 7A, the device layer 200 is formed with a first groove 290 that opens on the side opposite to the substrate layer 110. The first groove 290 is formed along each line 5. The first groove 290 surrounds the first mirror unit 31, the intermediate layer 23, and the second mirror unit 32 in each Fabry-Perot interference filter unit 1A and each dummy filter unit 2A. In each Fabry-Perot interference filter unit 1A, the first mirror unit 31, the intermediate layer 23, and the second mirror unit 32 are surrounded by a first groove 290 that is continuous in an annular shape. Similarly, in each dummy filter section 2A, the first mirror section 31, the intermediate layer 23, and the second mirror section 32 are surrounded by a first groove 290 that is continuous in an annular shape. Focusing on the adjacent filter portions 1A and 1A, the adjacent filter portions 1A and 2A, and the adjacent filter portions 2A and 2A, the first groove 290 is the peripheral portion 34 of one filter portion and the peripheral portion of the other filter portion. It corresponds to the area on 34. The first groove 290 is connected in the effective area 101 and the dummy area 102, and reaches the outer edge 110c of the substrate layer 110 when viewed from the opposite direction. The first groove 290 may surround at least the second mirror unit 32 in each Fabry-Perot interference filter unit 1A and each dummy filter unit 2A.

As shown in FIG. 7B, the stress adjusting layer 400 is formed with a second groove 470 that opens on the side opposite to the substrate layer 110. The second groove 470 is formed along each line 5. That is, the second groove 470 is formed so as to correspond to the first groove 290. Here, the fact that the second groove 470 corresponds to the first groove 290 means that the second groove 470 overlaps with the first groove 290 when viewed from the opposite direction. Therefore, the second groove 470 is connected in the effective area 101 and the dummy area 102, and reaches the outer edge 110c of the substrate layer 110 when viewed from the opposite direction.
[Wafer manufacturing method]

Next, a method for manufacturing the wafer 100 will be described with reference to FIGS. 8 to 13. 8 to 13, (a) is a cross-sectional view of a portion corresponding to the Fabry-Perot interference filter portion 1A, and (b) is a cross-sectional view of a portion corresponding to the dummy filter portion 2A.

First, as shown in FIG. 8, the antireflection layer 210 is formed on the first surface 110a of the substrate layer 110, and the antireflection layer 410 is formed on the second surface 110b of the substrate layer 110. Subsequently, a plurality of polysilicon layers and a plurality of silicon nitride layers are alternately laminated on the antireflection layers 210 and 410 to form the first mirror layer 220 on the antireflection layer 210 and to prevent reflection. A layer 420 is formed on the layer 410.

When forming the first mirror layer 220, the portion of the first mirror layer 220 along each line 5 is removed so that the surface of the antireflection layer 210 is exposed by etching. Further, by partially reducing the resistance of the predetermined polysilicon layer in the first mirror layer 220 by impurity doping, the first electrode 12, the second electrode 13, and the wiring 12a, for each portion corresponding to the substrate 11. Form 13a. Further, by etching, trenches 17 and 18 are formed on the surface of the first mirror layer 220 for each portion corresponding to the substrate 11.

Subsequently, as shown in FIG. 9, an intermediate layer 230 is formed on the first mirror layer 220 and on the surface of the exposed antireflection layer 210, and a layer 430 is formed on the layer 420. In the portion corresponding to each Fabry-Perot interference filter portion 1A, the intermediate layer 230 includes a planned removal portion 50 corresponding to the void S (see FIG. 3). Subsequently, by etching, the portion of the intermediate layer 230 and the antireflection layer 210 along each line 5 is removed so that the first surface 110a of the substrate layer 110 is exposed. Further, by the etching, a gap is formed in each portion of the intermediate layer 230 corresponding to the terminals 15 and 16 (see FIG. 3) for each portion corresponding to the substrate 11.

Subsequently, as shown in FIG. 10, a plurality of polysilicon layers and a plurality of silicon nitride layers are alternately laminated on each of the first surface 110a side and the second surface 110b side of the substrate layer 110, thereby intermediate. A second mirror layer 240 is formed on the layer 230 and on the first surface 110a of the exposed substrate layer 110, and a layer 440 is formed on the layer 430.

When forming the second mirror layer 240, the side surface 230a of the intermediate layer 230 facing each other along the line 5, the side surface 220a of the first mirror layer 220, and the side surface 210a of the antireflection layer 210 are combined with the second mirror layer 240. Cover with. Further, by partially reducing the resistance of the predetermined polysilicon layer in the second mirror layer 240 by impurity doping, the third electrode 14 and the wiring 14a are formed for each portion corresponding to the substrate 11.

Subsequently, as shown in FIG. 11, the surface of the polysilicon layer 27a (see FIG. 3) (that is, the polysilicon layer located closest to the first surface 110a) included in the second mirror layer 240 is exposed by etching. As such, the portion of the second mirror layer 240 along each line 5 is thinned. Further, by the etching, a gap is formed in each portion of the second mirror layer 240 corresponding to the terminals 15 and 16 (see FIG. 3) for each portion corresponding to the substrate 11. Subsequently, the terminals 15 and 16 are formed in the gap for each portion corresponding to the substrate 11, the terminals 15 and the wiring 12a are connected, and the terminals 16 and the wiring 13a and the wiring 14a are connected respectively. do.

Up to this point, the antireflection layer 210 and the device layer 200 are formed on the first surface 110a of the substrate layer 110, and the first groove 290 is formed on the device layer 200. The first groove 290 is a region where the device layer 200 is partially thinned along each line 5.

Subsequently, as shown in FIG. 12A, in the portion corresponding to each Fabry-Pérot interference filter portion 1A, a plurality of through holes extending from the surface 24a of the second laminated body 24 to the planned removal portion 50 by etching. 24b is formed on the second laminated body 24. At this time, as shown in FIG. 12B, a plurality of through holes 24b are not formed in the second laminated body 24 in the portion corresponding to each dummy filter portion 2A. Subsequently, as shown in FIG. 12, a light-shielding layer 450 is formed on the layer 440. Subsequently, by etching, the portion of the light shielding layer 450 and the stress adjusting layer 400 (that is, the layers 420, 430, 440) along each line 5 is removed so that the surface of the antireflection layer 410 is exposed. Further, by the etching, an opening 40a is formed for each portion corresponding to the substrate 11. Subsequently, a protective layer 460 is formed on the light-shielding layer 450, the surface of the exposed antireflection layer 410, the inner surface of the opening 40a, and the side surface of the stress adjusting layer 400 facing the second groove 470.

Up to this point, the antireflection layer 410, the stress adjusting layer 400, the light shielding layer 450 and the protective layer 460 are formed on the second surface 110b of the substrate layer 110, and the second groove 470 is formed on the stress adjusting layer 400. .. The second groove 470 is a region where the stress adjusting layer 400 is partially thinned along each line 5.

Subsequently, as shown in FIG. 13 (a), in the portion corresponding to each Fabry-Perot interference filter unit 1A, etching through a plurality of through holes 24b (for example, gas phase etching using hydrofluoric acid gas) is performed. , A plurality of planned removal portions 50 are removed all at once from the intermediate layer 230. As a result, in the portion corresponding to each Fabry-Perot interference filter portion 1A, a gap S is formed for each portion corresponding to the substrate 11. At this time, as shown in FIG. 13B, since the plurality of through holes 24b are not formed in the second laminated body 24 in the portion corresponding to each dummy filter portion 2A, the gap S in the intermediate layer 230. Is not formed.

As described above, in the effective area 101, as shown in FIG. 7A, a plurality of gaps S are formed between the first mirror portion 31 and the second mirror portion 32 facing each other. The Fabry-Perot interference filter unit 1A is configured. On the other hand, in the dummy area 102, as shown in FIG. 7B, a plurality of dummies are provided by providing the intermediate layer 23 between the first mirror portion 31 and the second mirror portion 32 facing each other. The filter unit 2A is configured.
[Inspection device and foreign matter removal method]

Next, the configuration of the inspection device in which the foreign matter removing method of one embodiment is implemented will be described. As shown in FIG. 14, the inspection device 500 includes a wafer support unit 510, an image pickup unit 520, a blow nozzle 530, a solenoid valve 540, and a control unit 550. The wafer support unit 510, the image pickup unit 520, and the blow nozzle 530 are arranged in a box (not shown). Here, the inspection target of the inspection device 500 is the wafer 100. As an example, the inspection device 500 has a function of performing an appearance inspection of each Fabry-Perot interference filter unit 1A on the wafer 100 (specifically, the surface of the wafer 100) and removes foreign matter detected in the appearance inspection by air blow. It has a function.

The wafer support portion 510 supports the wafer 100 so that the facing direction of the wafer 100 (that is, the direction in which the first mirror portion 31 and the second mirror portion 32 face each other) is parallel to the reference line RL. The wafer support portion 510 is, for example, a stage configured to be movable along a plane perpendicular to the reference line RL (at least along two directions parallel to the plane and orthogonal to each other). The wafer support portion 510 may be configured to be rotatable with a line parallel to the reference line RL as the center line. The relative movement of the image pickup unit 520 with respect to the wafer support unit 510 may be performed by moving the wafer support unit 510 as described above, by moving the image pickup unit 520, or by moving the wafer support unit 510. And may be done by moving both the imaging unit 520. The same applies to the relative movement of the blow nozzle 530 with respect to the wafer support portion 510.

The image pickup unit 520 images the wafer 100 (specifically, the surface of the wafer 100) supported by the wafer support unit 510. For example, the image pickup unit 520 emits light for observation along the reference line RL, detects the light reflected on the surface of the wafer 100 supported by the wafer support unit 510, and transmits the image pickup data to the control unit 550. It is a camera that outputs. The image pickup unit 520 is set to image each Fabry-Perot interference filter unit 1A on the wafer 100 at a magnification of, for example, 10 times or more. The image pickup unit 520 is arranged on the reference line RL. For example, by arranging a mirror member that changes the traveling direction of the observation light on the reference line RL, the image pickup unit 520 is arranged on the reference line RL. It may be placed in a position different from the above.

The blow nozzle 530 is a device that blows (blows) compressed air sent from the solenoid valve 540 to the Fabry-Perot interference filter unit 1A in which foreign matter F is detected by image processing based on image pickup data. The blow nozzle 530 may be an air gun type nozzle capable of blowing a relatively wide range at the same time, or may be a needle type nozzle capable of pinpointing a relatively narrow range. good. The air injected by the blow nozzle 530 is, for example, dry air, static electricity removing air capable of removing static electricity, nitrogen (N2), or the like.

The solenoid valve 540 is connected to an air tank (not shown), and switches ON / OFF of the distribution of compressed air compressed to a predetermined air pressure to the blow nozzle 530 based on a control signal from the control unit 550.

The control unit 550 is configured as a computer device including a processor, a memory, a storage, a communication device, and the like. In the control unit 550, various functions are realized by the processor executing predetermined software (program) read into the memory or the like and controlling reading and writing of data in the memory and the storage. For example, the control unit 550 realizes a foreign matter removing method described later by controlling the operation of each unit (wafer support unit 510, image pickup unit 520, blow nozzle 530, and solenoid valve 540).

In the inspection device 500 configured as described above, the operation of each unit is controlled by the control unit 550, so that the foreign matter removing method is implemented as follows. First, the wafer 100 to be inspected is prepared and supported by the wafer support portion 510. At this time, the wafer 100 is supported by the wafer support portion 510 so that the facing direction is parallel to the reference line RL.

Subsequently, the appearance inspection of each of the plurality of Fabry-Perot interference filter units 1A in the wafer 100 supported by the wafer support unit 510 is executed. Specifically, based on the image (imaging data) captured by the imaging unit 520, the surface of the second mirror layer 240 of each Fabry-Perot interference filter unit 1A opposite to the first mirror layer 220 (the wafer 100 is By cutting along each line 5, foreign matter adhering to the surface 24a) is detected. The above-mentioned foreign matter detection is executed, for example, as follows. First, the wafer 100 supported by the wafer support unit 510 is imaged by the image pickup unit 520. The image pickup data captured by the image pickup unit 520 is output to the control unit 550. The control unit 550 executes image processing on the position of the image pickup unit 520 and the image pickup data, and based on the result of the image processing, the appearance abnormality (foreign matter) on the surface of the Fabry-Perot interference filter unit 1A imaged by the image pickup unit 520. Is detected. The control unit 550 captures images by, for example, comparing the Fabry-Pérot interference filter unit 1A imaged by the image pickup unit 520 with a pattern image (an image of the Fabry-Pérot interference filter unit having no appearance abnormality) stored in advance. The foreign matter adhering to the surface of the Fabry-Perot interference filter unit 1A is detected. The control unit 550 stores information indicating the position (or region) of the detected foreign matter (for example, coordinate information (or information indicating a certain region depending on the range of coordinates)).

Instead of executing the image processing as described above (comparison with the pattern image in this embodiment), the control unit 550 displays the image pickup data on the display (not shown) provided in the inspection device 500 to check for the presence or absence of foreign matter. The operator may be allowed to visually confirm. When a foreign substance is found by visual confirmation, the operator uses, for example, an input device (not shown) such as a keyboard included in the inspection device 500 to specify a region corresponding to the foreign substance in the imaging data. In this case, the control unit 550 may store information indicating an area designated by the operator.

Subsequently, the control unit 550 controls the operation of the blow nozzle 530 and the solenoid valve 540 in order to remove the detected foreign matter F.

First, the control unit 550 adjusts the position of the blow nozzle 530 based on the position of the detected foreign matter F. That is, the control unit 550 adjusts the position of the airflow peak of the air discharged from the blow nozzle 530. The airflow peak is the part where the air flow velocity is the highest. In the present embodiment, air is discharged from the tip portion 530a of the blow nozzle 530 along the direction D parallel to the extending direction of the blow nozzle 530. In this case, the position of the airflow peak is a position on a straight line along the direction D from the tip portion 530a of the blow nozzle 530. In the present embodiment, the control unit 550 adjusts the position of the airflow peak of the air discharged from the blow nozzle 530 so as to match the position of the foreign matter F. Specifically, the control unit 550 controls the position and posture of the blow nozzle 530 so that the foreign matter F overlaps the position on a straight line along the direction D from the tip portion 530a of the blow nozzle 530.

Subsequently, the control unit 550 controls the opening / closing operation of the solenoid valve 540, and causes compressed air having a predetermined air pressure to be sent to the blow nozzle 530 for a predetermined time. As a result, air is discharged from the tip portion 530a of the blow nozzle 530, and the foreign matter F can be removed by blowing off the foreign matter F with the air.

The control unit 550 may intentionally adjust the position of the airflow peak to a position where it does not overlap with the foreign matter F. For example, when the foreign matter F is present on the portion of the second mirror layer 240 of the Fabry-Perot interference filter unit 1A that overlaps with the void S when viewed from the opposite direction (hereinafter, simply referred to as “membrane portion”), the control unit 550 may be used. The position and posture of the blow nozzle 530 may be controlled so that air is blown to the region on the membrane portion where the foreign matter F does not exist (the region where the plurality of through holes 24b are formed). In this case, the air blown onto the surface of the second mirror layer 240 can enter the void S through the plurality of through holes 24b. The air that has entered the void S is pushed out by the air that newly enters the void S, so that the through hole 24b is different from the through hole 24b through which the air that newly enters the void S flows. It is discharged to the surface side of the second mirror layer 240 via the above. The foreign matter F adhering to the surface of the second mirror layer 240 can be blown up by the air discharged to the outside from the void S in this way.

Here, when the blow nozzle 530 is the above-mentioned air gun type nozzle, not only the periphery of the foreign matter F (for example, the surface of the Fabry-Perot interference filter portion 1A to which the foreign matter F is attached) but also the periphery thereof (foreign matter F is present). The area on the wafer 100 including the Fabry-Pérot interference filter unit 1A other than the attached Fabry-Pérot interference filter unit 1A) can also be blown at the same timing. Therefore, the foreign matter F can be blown off to a position relatively far from the wafer 100 by the air, and the possibility that the foreign matter F reattaches to the surface of the other Fabry-Perot interference filter portion 1A on the wafer 100 can be reduced.

On the other hand, when the blow nozzle 530 is the needle type nozzle described above, only the foreign matter F or the periphery of the foreign matter F (for example, the surface of the Fabry-Perot interference filter portion 1A to which the foreign matter F is attached) is blown pinpointly. Is possible. In this case, even if the solenoid valve 540 malfunctions and the blow conditions change drastically (for example, the air suddenly becomes high pressure), the range of influence is limited. Therefore, damage to the entire wafer 100 can be minimized.

Next, with reference to FIGS. 15 and 16, the results of the characteristic evaluation of the Fabry-Perot interference filter before and after the air blow performed by the present inventors will be described. The characteristic evaluation is to compare the characteristics of the Fabry-Pérot interference filter before and after the air blow by performing air blow by the blow nozzle 530 described above on the membrane portion of the Fabry-Pérot interference filter in excess of the amount required for normal foreign matter removal. Made by. The characteristic evaluation was performed on the individualized Fabry-Perot interference filter 1 obtained by cutting the wafer 100 along each line 5, but the Fabry-Pérot interference filter unit in the wafer 100. It is considered that the same result can be obtained when the air blow is performed on 1A.

The main measurement conditions and implementation procedures are as follows.
<Measurement conditions>
・ Blow nozzle type: Needle type ・ Blow nozzle syringe capacity: 10 ml
・ Pressure of air discharged from blow nozzle: 0.5MPa
・ Blow time: 1ms
-Distance between the tip of the blow nozzle (tip of the needle) and the surface of the membrane of the Fabry-Perot interference filter: 1 cm or less <Experimental procedure>
1. 1. The sample (Fabry-Pérot interference filter 1) was set on the stage of the device for character evaluation under a normal temperature environment.
2. 2. The characteristics before air blow (peak transmission wavelength with respect to the filter control voltage and wavelength resolution with respect to the peak transmission wavelength) were measured.
3. 3. The sample was removed, and air blow was performed on the sample based on the above measurement conditions.
4. The sample was set on the stage again in a normal temperature environment.
5. The characteristics after air blow (peak transmission wavelength with respect to the filter control voltage and wavelength resolution with respect to the peak transmission wavelength) were measured.

FIG. 15 shows the relationship of the peak transmission wavelength (the wavelength most easily transmitted through the light transmission region 1a) with respect to the filter control voltage (that is, the voltage between the first electrode 12 and the third electrode 14). As shown in FIG. 15, the maximum deviation amount (absolute value) of the peak transmission wavelength was about 0.9 nm before and after the air blow. It is highly probable that the cause of this deviation amount is that the sample has been removed from the stage once for air blow, and that there is an error due to the measurement environment. Therefore, it is considered that the deviation amount is an error of an allowable level, and the air blow has almost no effect on the characteristics of the Fabry-Perot interference filter (relationship of the peak transmission wavelength with respect to the filter control voltage).

FIG. 16 shows the relationship of wavelength resolution (FWHM) with respect to the peak transmission wavelength. As shown in FIG. 16, the difference in wavelength resolution at the same peak transmission wavelength before and after the air blow was about 0.3 nm at the maximum. That is, it was confirmed that the characteristics of the Fabry-Pérot interference filter (relationship of wavelength resolution with respect to the peak transmission wavelength) hardly change (within a sufficiently acceptable error range) by air blow to the membrane portion of the Fabry-Pérot interference filter. ..
[Manufacturing method of Fabry-Perot interference filter]

Next, a method of cutting out the Fabry-Pérot interference filter 1 from the wafer 100 (a method of manufacturing the Fabry-Pérot interference filter 1) will be described with reference to FIGS. 17 and 18. 17 and 18, FIG. 17A is a cross-sectional view of a portion corresponding to the Fabry-Perot interference filter portion 1A, and FIG. 18B is a cross-sectional view of a portion corresponding to the dummy filter portion 2A.

First, as shown in FIG. 17, the expanding tape 60 is attached on the protective layer 460 (that is, on the side of the second surface 110b). Subsequently, with the expand tape 60 attached to the second surface 110b side, the laser beam L is irradiated from the side opposite to the expand tape 60, and the condensing point of the laser beam L is positioned inside the substrate layer 110. The focusing point of the laser beam L is relatively moved along each line 5. That is, the laser beam L is incident on the substrate layer 110 from the side opposite to the expanded tape 60 via the surface of the polysilicon layer exposed in the first groove 290.

Then, by the irradiation of the laser beam L, the modified region 7 is formed inside the substrate layer 110 along each line 5. The modified region 7 is a region in which the density, refractive index, mechanical strength, and other physical properties are different from those of the surroundings, and is a region that is a starting point of a crack extending in the thickness direction of the substrate layer 110. Is. The modified region 7 includes, for example, a melting treatment region (meaning at least one of a region once melted and then resolidified, a region in a molten state, and a region in a state of being resolidified from melting) and a crack region. , Dielectric breakdown region, refractive index change region, etc., and there is also a region where these are mixed. Further, the modified region 7 includes a region in which the density of the modified region 7 is changed in comparison with the density of the non-modified region in the material of the substrate layer 110, a region in which lattice defects are formed, and the like. When the material of the substrate layer 110 is single crystal silicon, the modified region 7 can be said to be a high dislocation density region. The number of rows of the modified regions 7 arranged in the thickness direction of the substrate layer 110 for each line 5 is appropriately adjusted according to the thickness of the substrate layer 110.

Subsequently, as shown in FIG. 18, by expanding the expand tape 60 attached to the second surface 110b side, the thickness of the substrate layer 110 from the modified region 7 formed inside the substrate layer 110 is increased. The crack is extended in the direction, and the substrate layer 110 is cut into a plurality of substrates 11 along each line 5. At this time, the polysilicon layer of the second mirror layer 240 is cut along each line 5 in the first groove 290, and the antireflection layer 410 and the protective layer 460 are cut along each line 5 in the second groove 470. Will be done. As a result, a plurality of Fabry-Perot interference filters 1 and a plurality of dummy filters 2 that are separated from each other on the expand tape 60 are obtained.
[Structure of the photodetector of the first embodiment]

Next, the configuration of the photodetector 10 of the first embodiment including the Fabry-Perot interference filter 1 will be described. As shown in FIG. 19, the photodetector 10 includes a package 71. Package 71 is a CAN package having a stem 72 and a cap 73. The cap 73 is integrally composed of a side wall 74 and a top wall 75. The stem 72 and the cap 73 are made of a metal material and are airtightly joined to each other. In the package 71 made of a metal material, the shape of the side wall 74 is a cylinder with the line 9 as the center line. The stem 72 and the top wall 75 face each other in a direction parallel to the line 9, and close both ends of the side wall 74, respectively.

A wiring board 76 is fixed to the inner surface 72a of the stem 72. As the substrate material of the wiring board 76, for example, silicon, ceramic, quartz, glass, plastic or the like can be used. A photodetector (photodetector) 77 and a temperature detector (not shown) such as a thermistor are mounted on the wiring board 76. The photodetector 77 is arranged on the line 9. More specifically, the photodetector 77 is arranged so that the center line of the light receiving portion coincides with the line 9. The photodetector 77 is an infrared detector such as a quantum sensor using InGaAs or the like, a thermal sensor using a thermopile or a bolometer, or the like. When detecting light in each wavelength range of ultraviolet, visible, and near-infrared, for example, a silicon photodiode or the like can be used as the photodetector 77. The photodetector 77 may be provided with one light receiving unit, or may be provided with a plurality of light receiving units in an array. Further, a plurality of photodetectors 77 may be mounted on the wiring board 76. The temperature detector may be arranged, for example, at a position close to the Fabry-Perot interference filter 1 so that the temperature change of the Fabry-Perot interference filter 1 can be detected.

A plurality of spacers 78 are fixed on the wiring board 76. As the material of each spacer 78, for example, silicon, ceramic, quartz, glass, plastic or the like can be used. The Fabry-Perot interference filter 1 is fixed on the plurality of spacers 78 by, for example, an adhesive. The Fabry-Perot interference filter 1 is arranged on the line 9. More specifically, the Fabry-Perot interference filter 1 is arranged so that the center line of the light transmission region 1a coincides with the line 9. The spacer 78 may be integrally configured with the wiring board 76. Further, the Fabry-Perot interference filter 1 may be supported by one spacer 78 instead of a plurality of spacers 78.

A plurality of lead pins 81 are fixed to the stem 72. More specifically, each lead pin 81 penetrates the stem 72 while maintaining electrical insulation and airtightness with the stem 72. Each of the electrode pad provided on the wiring board 76, the terminal of the photodetector 77, the terminal of the temperature detector, and the terminal of the fabric perow interference filter 1 are electrically connected to each lead pin 81 by a wire 82. There is. The photodetector 77, the temperature detector, and the Fabry-Perot interference filter 1 may be electrically connected to each lead pin 81 via the wiring board 76. For example, each terminal and the electrode pad provided on the wiring board 76 may be electrically connected, and the electrode pad and each lead pin 81 may be connected by a wire 82. As a result, it is possible to input / output an electric signal to each of the photodetector 77, the temperature detector, and the Fabry-Perot interference filter 1.

An opening 71a is formed in the package 71. More specifically, the opening 71a is formed on the top wall 75 of the cap 73 so that its center line coincides with the line 9. When viewed from a direction parallel to the line 9, the shape of the opening 71a is a circular shape. A light transmitting member 83 is arranged on the inner surface 75a of the top wall 75 so as to close the opening 71a. The light transmitting member 83 is airtightly joined to the inner surface 75a of the top wall 75. The light transmitting member 83 has a light incident surface 83a, a light emitting surface (inner surface) 83b, and a side surface 83c facing each other in a direction parallel to the line 9. The light incident surface 83a of the light transmitting member 83 is substantially flush with the outer surface of the top wall 75 at the opening 71a. The side surface 83c of the light transmitting member 83 is in contact with the inner surface 74a of the side wall 74 of the package 71. That is, the light transmitting member 83 reaches the inside of the opening 71a and the inner surface 74a of the side wall 74. Such a light transmitting member 83 is formed by arranging glass pellets inside the cap 73 with the opening 71a facing down and melting the glass pellets. That is, the light transmitting member 83 is formed of fused glass.

A bandpass filter 84 is fixed to the light emitting surface 83b of the light transmitting member 83 by an adhesive member 85. That is, the adhesive member 85 fixes the bandpass filter 84 to the inner surface 75a of the top wall 75 via the light transmitting member 83 joined to the inner surface 75a of the top wall 75. The bandpass filter 84 is light in the measurement wavelength range of the light detection device 10 (light in a predetermined wavelength range among the light transmitted through the light transmission member 83, and is incident on the light transmission region 1a of the fabric perot interference filter 1. It selectively transmits light to be transmitted (that is, transmits only light in the wavelength range). The shape of the bandpass filter 84 is a quadrangular plate. More specifically, the bandpass filter 84 has a light incident surface 84a and a light emitting surface 84b facing each other in a direction parallel to the line 9, and four side surfaces 84c. The bandpass filter 84 has a height of a dielectric multilayer film (for example, TiO ₂ , Ta ₂ O ₅ or the like) on the surface of a light transmitting member formed in a rectangular plate shape by a light transmitting material (for example, silicon, glass, etc.). A multilayer film composed of a combination of a refracting material and a low refraction material such as SiO ₂ and MgF ₂ ) is formed.

The adhesive member 85 has a first portion 85a arranged in the entire region of the light incident surface 84a of the bandpass filter 84. That is, the first portion 85a is a portion of the adhesive member 85 arranged between the light emitting surface 83b of the light transmitting members 83 facing each other and the light incident surface 84a of the bandpass filter 84. Further, the adhesive member 85 has a second portion 85b protruding outward from the outer edge of the bandpass filter 84 when viewed from a direction parallel to the line 9. The second portion 85b reaches the inner surface 74a of the side wall 74 and is in contact with the inner surface 74a of the side wall 74. Further, the second portion 85b is in contact with the side surface 84c of the bandpass filter 84.

In the photodetector 10 configured as described above, when light is incident on the bandpass filter 84 from the outside through the opening 71a, the light transmitting member 83, and the adhesive member 85, light in a predetermined wavelength range is selected. Is transparent. When the light transmitted through the bandpass filter 84 is incident on the light transmission region 1a of the Fabry-Perot interference filter 1, the light having a predetermined wavelength is selectively transmitted from the light in a predetermined wavelength range. The light transmitted through the light transmission region 1a of the Fabry-Perot interference filter 1 enters the light receiving portion of the photodetector 77 and is detected by the photodetector 77. That is, the photodetector 77 converts the light transmitted through the Fabry-Perot interference filter 1 into an electric signal and outputs it. For example, the photodetector 77 outputs an electric signal having a magnitude corresponding to the intensity of the light incident on the light receiving unit.
[Manufacturing method of the photodetector of the first embodiment]

Next, a method of manufacturing the photodetector 10 will be described. As shown in FIG. 20, first, a stem 72 to which the Fabry-Perot interference filter 1 and the photodetector 77 are fixed is prepared. Specifically, a part of the photodetector 10 in the state immediately before the cap 73 is attached is prepared. For example, one or more of the stems 72 are mounted on a stage (not shown) for performing the visual inspection and air blow described above.

Subsequently, by the same method as the visual inspection by the inspection device 500 described above, the surface 24a of the second laminated body 24 of the Fabry-Perot interference filter 1 fixed to the stem 72 on the opposite side of the first laminated body 22. The attached foreign matter F is detected. Subsequently, air whose airflow peak position is adjusted based on the detected position of the foreign matter F is blown onto the surface 24a of the second laminated body 24 by the same method as the air blow by the inspection device 500 described above. As a result, the foreign matter F is removed from the surface 24a of the second laminated body 24. Subsequently, after the foreign matter F is removed as described above, the cap 73 is joined to the stem 72 to which the Fabry-Perot interference filter 1 and the photodetector 77 are fixed. As a result, the photodetector 10 shown in FIG. 19 is obtained. When a plurality of the above stems 72 are mounted on the stage, a plurality of Fabry-Perot interference filters 1 fixed to the plurality of stems 72 by using an air gun type nozzle capable of blowing over a wide range as described above. However, air blow can be performed all at once. Further, by performing the above-mentioned air blow on a portion other than the surface 24a of the second laminated body 24 of the Fabry-Perot interference filter 1, the foreign matter F adhering to the surface 24a is removed from the surface 24a and the foreign matter F is removed. Is preferably discharged out of the package.
[Structure of the photodetector of the second embodiment]

Next, with reference to FIGS. 21 and 22, the configuration of the photodetector 10A of the second embodiment including the Fabry-Perot interference filter 1 will be described. In FIG. 22, the lid substrate 94 and the like, which will be described later, are omitted. As shown in FIGS. 21 and 22, the photodetector 10A differs from the above-mentioned photodetector 10 in that it is configured as an SMD (Surface Mount Device). The photodetector 10A includes a photodetector 91, a temperature compensating element (not shown), and an SMD package 92 containing a fabric perot interference filter 1. The SMD package 92 has a support 93 that supports the Fabry-Perot interference filter 1 and the photodetector 91, and a lid substrate 94 that is joined to the support 93. The support 93 has a first substrate 93a, a second substrate 93b, a third substrate 93c, a fourth substrate 93d, and a fifth substrate 93e.

The first substrate 93a, the second substrate 93b, the third substrate 93c, the fourth substrate 93d, the fifth substrate 93e, and the lid substrate 94 are laminated in this order. An opening is provided in the central portion of each of the second substrate 93b, the third substrate 93c, the fourth substrate 93d, and the fifth substrate 93e. When viewed from the stacking direction (direction A) of these substrates, the opening of the third substrate 93c includes the opening of the second substrate 93b. When viewed from the direction A, the opening of the fourth substrate 93d includes the opening of the third substrate 93c. When viewed from the direction A, the opening of the fifth substrate 93e includes the opening of the fourth substrate 93d. As a result, a part of the surface of each of the first substrate 93a, the second substrate 93b, the third substrate 93c, and the fourth substrate 93d is exposed to the opening of the fifth substrate 93e.

A photodetector 91 and a temperature compensation element (not shown) are mounted on the surface of the exposed first substrate 93a. A plurality of electrode pads (not shown) are provided on the back surface of the first substrate 93a. Each terminal of the photodetector 91 and each terminal of the temperature compensating element are electrically connected to the electrode pad by the wiring provided on the first substrate 93a or by the wiring provided on the wire 95 and the substrates 93a and 93b. Is connected.

A Fabry-Perot interference filter 1 is fixed to the surface of the exposed third substrate 93c by an adhesive member 96. The upper surfaces of the terminals 15 and 16 of the Fabry-Perot interference filter 1 are at the same height as the upper surface of the fourth substrate 93d. A pad electrically connected to the electrode pad is provided on the upper surface of the fourth substrate 93d, and the terminals 15 and 16 are connected to the pad on the upper surface of the fourth substrate 93d by a wire 95. The terminals 15 and 16 of the Fabry-Perot interference filter 1 are electrically connected to the electrode pads by the wires provided on the wires 95 and the substrates 93a, 93b, 93c, 93d. The third substrate 93c functions as a support member for supporting the Fabry-Perot interference filter 1 on the first substrate 93a and the second substrate 93b.

As the material of the first substrate 93a, the second substrate 93b, the third substrate 93c, the fourth substrate 93d, and the fifth substrate 93e, for example, ceramics, resins, and the like can be used. In particular, in order to reduce the difference in the coefficient of thermal expansion between the fabric perlow interference filter 1 and the third substrate 93c, the material of the third substrate 93c has a coefficient of thermal expansion as compared with the material of the fabric perow interference filter 1. Is preferably equivalent.

The material of the adhesive member 96 for adhering the fabric perow interference filter 1 and the third substrate 93c is a flexible resin material (for example, a resin material such as silicone-based, urethane-based, epoxy-based, acrylic-based, or hybrid). Therefore, it may be conductive or non-conductive). The resin material is preferably selected from materials having a Young's modulus of less than 1000 MPa, and more preferably selected from materials having a Young's modulus of less than 10 MPa. Further, it is preferable that the resin material is selected from materials whose glass transition temperature deviates from the operating environment temperature of the photodetector 10A. For example, if an adhesive containing a silicone-based resin material is used as the material of the adhesive member 96, the Young's modulus after curing is less than 10 MPa, and the glass transition temperature is the operating environment temperature (for example, about 5 to 40 ° C.). It will be about -50 to -40 ° C, which is lower than that.

Here, the elastic modulus of the adhesive member 96 for adhering the fabric perow interference filter 1 and the third substrate 93c is smaller than the elastic modulus of the third substrate 93c. The elastic modulus of the adhesive member 96 is the elasticity of the adhesive member (not shown) that adheres the first substrate 93a, the second substrate 93b, the third substrate 93c, the fourth substrate 93d, the fifth substrate 93e, and the lid substrate 94 to each other. Less than the rate. For example, an adhesive containing an epoxy-based resin material can be used as a material for an adhesive member that adheres the first substrate 93a, the second substrate 93b, the third substrate 93c, the fourth substrate 93d, the fifth substrate 93e, and the lid substrate 94 to each other. If used, the Young rate after curing will be 100 MPa or more.

The lid substrate 94 has a light transmitting substrate 94a and a light shielding layer 94b. The light transmitting substrate 94a is fixed on the fifth substrate 93e by an adhesive member (not shown). As the material of the light transmission substrate 94a, a material corresponding to the measurement wavelength range of the light detection device 10A (for example, glass, silicon, germanium, etc.) can be used. The light-shielding layer 94b is formed on the surface of the light-transmitting substrate 94a. As the material of the light-shielding layer 94b, a light-shielding material or a light-absorbing material (for example, a metal such as aluminum, a metal oxide such as chromium oxide, a black resin, or the like) can be used. The light-shielding layer 94b is provided with an opening 94c. The light transmission region 1a and the opening 94c face each other in the direction A. The light-shielding layer 94b may be formed on the back surface of the light-transmitting substrate 94a. Further, a light reflection antireflection layer may be formed on at least one of the front surface and the back surface of the light transmission substrate 94a. Further, as the light transmission substrate 94a, a bandpass filter that transmits only light in the measurement wavelength range may be used.

In the light detection device 10A configured as described above, when light is incident on the light transmission region 1a of the Fabry-Perot interference filter 1 from the outside through the opening 94c and the light transmission substrate 94a, the first mirror in the light transmission region 1a Light having a predetermined wavelength is selectively transmitted according to the distance between the unit 31 (see FIG. 3) and the second mirror unit 32 (see FIG. 3). The light transmitted through the first mirror unit 31 and the second mirror unit 32 enters the light receiving unit 91a of the photodetector 91 and is detected by the photodetector 91. In the light detection device 10A, the first mirror unit 31 and the second mirror unit 31 and the second mirror unit 31 are changed while the voltage applied to the Fabry-Perot interference filter 1 is changed (that is, the distance between the first mirror unit 31 and the second mirror unit 32 is changed). A spectroscopic spectrum can be obtained by detecting the light transmitted through the mirror unit 32 with the light detector 91.
[Manufacturing method of the photodetector of the second embodiment]

Next, a method of manufacturing the photodetector 10A will be described. As shown in FIG. 23, first, a plurality of Fabry-Perot interference filters 1 arranged one-dimensionally or two-dimensionally, a plurality of optical detectors 91 provided corresponding to the plurality of Fabry-Perot interference filters 1, and a plurality of optical detectors 91. A plurality of Fabry-Perot interference filters 1 and a support layer 930 for supporting the plurality of optical detectors 91 are prepared. The support layer 930 is a layer to be cut along the cutting line L1 to become a plurality of first substrate 93a, second substrate 93b, third substrate 93c, fourth substrate 93d, and fifth substrate 93e, respectively. It has a first substrate layer 930a, a second substrate layer 930b, a third substrate layer 930c, a fourth substrate layer 930d, and a fifth substrate layer 930e.

Subsequently, for each of the plurality of Fabry-Perot interference filters 1 supported by the support layer 930 by the same method as the visual inspection by the inspection device 500 described above, the side opposite to the first laminated body 22 of the second laminated body 24. Foreign matter F adhering to the surface 24a of the above is detected. Subsequently, air whose airflow peak position is adjusted based on the detected position of the foreign matter F is blown onto the surface 24a of the second laminated body 24 by the same method as the air blow by the inspection device 500 described above. As a result, the foreign matter F is removed from the surface 24a of the second laminated body 24 of the Fabry-Perot interference filter 1 in which the foreign matter F is detected.

Subsequently, after the foreign matter F is removed from each of the plurality of Fabry-Perot interference filters 1 supported by the support layer 930 as described above, it corresponds to the plurality of Fabry-Perot interference filters 1 as shown in FIG. The lid substrate layer 940 in which the plurality of openings 94c are formed is joined to the support layer 930 (here, the upper surface of the fifth substrate layer 930e). Specifically, the lid substrate layer 940 is joined to the support layer 930 so that each of the plurality of openings 94c faces each of the plurality of Fabry-Perot interference filters 1 in the direction A. The lid substrate layer 940 is a layer to be cut along the cutting line L1 to become a plurality of lid substrates 94. The lid substrate layer 940 has a light transmitting substrate layer 940a and a light shielding layer 940b. The light transmitting substrate layer 940a is a layer to be formed into a plurality of light transmitting substrates 94a by cutting the lid substrate layer 940 along the cutting line L1. The light-shielding layer 940b is a layer to be formed into a plurality of light-shielding layers 94b by cutting the lid substrate layer 940 along the cutting line L1. By joining the lid substrate layer 940 to the support layer 930 as described above, a plurality of photodetectors 10A connected one-dimensionally or two-dimensionally in the cutting line L1 can be obtained.

Subsequently, the portion where the lid substrate layer 940 and the support layer 930 are joined is cut along the cutting line L1. This gives the individual photodetectors 10A (see FIGS. 21 and 22).
[Actions and effects of foreign matter removal method and manufacturing method of photodetector]

The above-mentioned foreign matter removing method was detected as a step of preparing a fabric perow interference filter 1 and a step of detecting foreign matter F adhering to the surface 24a of the second laminated body 24 opposite to the first laminated body 22. This includes a step of removing the foreign matter F from the surface 24a of the second laminated body 24 by blowing air whose position of the airflow peak is adjusted based on the position of the foreign matter F onto the surface 24a of the second laminated body 24. When air blowing is performed on the wafer 100, the Fabry-Perot interference filter 1, the first laminated body 22, and the second laminated body 24 are provided with the Fabry-Pérot interference filter unit 1A, the first mirror layer 220, and the second laminated body 24. It can be read as the mirror layer 240, respectively.

According to the above-mentioned foreign matter removing method, the foreign matter F adhering to the surface 24a of the second laminated body 24 of the Fabry-Perot interference filter 1 can be detected, and the foreign matter F can be removed by blowing air. Since the position of the air flow peak of the air is adjusted based on the position of the detected foreign matter F, the foreign matter F can be appropriately removed by blowing the air. As described above, according to the above-mentioned foreign matter removing method, the foreign matter F adhering to the Fabry-Perot interference filter 1 can be effectively removed, and the Fabry-Perot interference filter 1 can be obtained with a good yield.

Here, in the Fabry-Perot interference filter 1, a gap S is provided between a portion of the first laminated body 22 facing each other including at least the first mirror portion 31 and a portion of the second laminated body 24 including at least the second mirror portion 32. Is formed. That is, the portion (membrane portion) of the second laminated body 24 that overlaps with the void S when viewed from the opposite direction has a so-called membrane structure and is a relatively fragile portion. For this reason, conventionally, no attempt has been made to remove foreign matter by a method in which a stress that is a load is generated on the membrane portion and there is a concern that the membrane portion may be deformed or damaged. It was often treated as a defective product. However, as a result of diligent research by the present inventors, the method of blowing air does not significantly affect the characteristics of the Fabry-Perot interference filter 1, although it is a method of generating stress in the membrane portion. It was confirmed that the foreign matter F can be removed.

Further, in the step of removing the foreign matter F, the position of the airflow peak is adjusted so as to match the position of the foreign matter F. In this case, the foreign matter F can be removed more reliably by directly hitting the foreign matter F with the airflow peak (that is, the portion where the air flow velocity is the largest).

Further, in the second laminated body 24, the portion (membrane portion) where the first mirror portion 31 and the second mirror portion 32 overlap with the voids when viewed from the directions facing each other is from the surface 24a of the second laminated body 24. A plurality of through holes 24b leading to the void S are formed, and in the step of removing the foreign matter F, air is blown to at least the region of the surface 24a of the second laminated body 24 where the plurality of through holes 24b are formed. In this case, the air blown to the surface 24a of the second laminated body 24 can be allowed to enter the void S through the plurality of through holes 24b. The air that has entered the void S is pushed out by the air that newly enters the void S, so that the through hole 24b is different from the through hole 24b through which the air that newly enters the void S flows. Is discharged to the surface 24a side of the second laminated body 24 via the above. The foreign matter F adhering to the surface 24a of the second laminated body 24 can be blown up by the air discharged to the outside from the void S in this way. Thereby, the foreign matter F adhering to the Fabry-Perot interference filter 1 can be removed more effectively.

Further, in the step of preparing the Fabry-Perot interference filter 1, a wafer 100 in which a plurality of Fabry-Perot interference filters 1 are two-dimensionally connected is prepared, and the step of detecting the foreign matter F and the step of removing the foreign matter F are the wafers. It may be carried out for the Fabry-Perot interference filter constituting 100 (that is, the Fabry-Perot interference filter unit 1A). That is, foreign matter may be removed by air blowing at the wafer stage. In this case, when the foreign matter F adheres to the Fabry-Perot interference filter portion 1A constituting the wafer 100, the foreign matter F can be removed by blowing air. As a result, when inspecting each of the plurality of Fabry-Pérot interference filter units 1A constituting the wafer 100, the foreign matter F was removed without immediately determining the Fabry-Pérot interference filter unit 1A to which the foreign matter F was attached as a defect. The Fabry-Perot interference filter unit 1A can be used as a non-defective product in a subsequent process. Therefore, the yield of the Fabry-Perot interference filter 1 can be improved. When air blowing is performed on the wafer 100 in this way, not only the foreign matter F is removed from the surface of the Fabry-Perot interference filter unit 1A in which the foreign matter F is found, but also the foreign matter F is the surface of the wafer 100. It is preferable to blow the air over a relatively wide area so that it can be removed from the whole.

Further, in the step of preparing the Fabry-Perot interference filter 1, the individualized Fabry-Pérot interference filter 1 may be prepared. That is, foreign matter may be removed by air blowing at the chip stage. For example, when foreign matter is removed by blowing air onto the Fabry-Perot interference filter unit 1A constituting the wafer 100, the foreign matter F is scattered on the other Fabry-Perot interference filter unit 1A constituting the wafer 100, and the foreign matter F is scattered. There is a risk of adversely affecting other Fabry-Perot interference filter units 1A. On the other hand, when the Fabry-Pérot interference filter 1 is separated as described above, foreign matter is removed by blowing air onto the Fabry-Pérot interference filter 1 to remove foreign matter from the Fabry-Pérot interference filter 1 as described above. It is possible to prevent the occurrence of an adverse effect on the part 1A.

Further, in the method for manufacturing a photodetector according to the first embodiment described above, a package 71 having a cap 73 in which an opening 71a for incident light is formed and a stem 72 joined to the cap 73, and a package 71 are arranged in the package 71. It is a manufacturing method of a photodetector 10 including a Fabry-Pérot interference filter 1 and a photodetector 77 arranged in a package 71 to detect light transmitted through the Fabry-Pérot interference filter 1. This manufacturing method comprises a step of preparing a stem 72 to which a fabric perow interference filter 1 and an optical detector 77 are fixed, and a surface 24a of a second laminated body 24 of the fabric perow interference filter 1 fixed to the stem 72. The surface of the second laminated body 24 is blown to the surface 24a of the second laminated body 24 by the step of detecting the attached foreign matter F and the air whose position of the airflow peak is adjusted based on the position of the detected foreign matter F. A step of removing the foreign matter F from the 24a and a step of joining the cap 73 to the stem 72 after the step of removing the foreign matter F are included.

According to the method of manufacturing the photodetector of the first embodiment, the surface of the second laminated body 24 of the Fabry-Perot interference filter 1 is in a state where the Fabry-Perot interference filter 1 and the photodetector 77 are fixed to the stem 72. The foreign matter F adhering to the 24a can be detected and the foreign matter F can be removed by blowing air. That is, it is possible to appropriately detect and remove the foreign matter F adhering to the Fabry-Perot interference filter 1 in the state immediately before the photodetector 10 is obtained. Here, since the assembly work of the photodetector 10 is not always performed in a clean room with high cleanliness, there is a possibility that foreign matter F adheres to the surface 24a of the Fabry-Perot interference filter 1 during the assembly work. May be relatively high. According to the above manufacturing method, in the final stage of the manufacturing process of the light detection device 10, foreign matter F adhering to the Fabry-Perot interference filter 1 can be removed without significantly affecting the characteristics of the Fabry-Perot interference filter 1. can. As a result, the non-defective rate of the photodetector 10 which is the final product can be improved, and the photodetector 10 can be obtained with a good yield.

Further, in the method of manufacturing the photodetector of the second embodiment described above, the SMD package 92 having the lid substrate 94 and the support 93 bonded to the lid substrate 94 and the Fabry-Perot interference filter arranged in the SMD package 92 are used. It is a manufacturing method of a photodetector 10A including 1 and a photodetector 91 which is arranged in an SMD package 92 and detects light transmitted through a Fabry-Perot interference filter 1. In this manufacturing method, a plurality of fabric perow interference filters 1 arranged in one dimension or two dimensions, a plurality of photodetectors 91 provided corresponding to the plurality of fabric perot interference filters 1, and a plurality of fabric perot interferences are used. A step of preparing a support layer 930 that supports the filter 1 and the plurality of photodetectors 91, which is to be cut into the plurality of supports 93, and a step of preparing the support layer 930, and each of the plurality of fabric perot interference filters 1. The step of detecting the foreign matter F adhering to the surface 24a of the second laminated body 24 and the air whose airflow peak position is adjusted based on the position of the detected foreign matter F are applied to the surface 24a of the second laminated body 24. After the step of removing the foreign matter F from the surface 24a of the second laminated body 24 and the step of removing the foreign matter F by spraying, the lid substrate layer 940 to be cut into the plurality of lid substrates 94 is attached to the support layer 930. By joining, a step of obtaining a plurality of photodetectors 10A connected one-dimensionally or two-dimensionally, and by cutting a portion where the lid substrate layer 940 and the support layer 930 are joined, each photodetector Includes a step of obtaining 10A.

According to the method for manufacturing the optical detection device of the second embodiment, a plurality of Fabry-Perot interference filters 1 are attached to the surface 24a of the second laminated body 24 of each Fabry-Perot interference filter 1 in a state of being supported by the support layer 930. The foreign matter F can be detected and the foreign matter F can be removed by blowing air. That is, the state immediately before the light detection device 10A is obtained (specifically, the state immediately before the space in which each Fabry-Perot interference filter 1 is accommodated is sealed by joining the lid substrate layer 940 to the support layer 930). In, the foreign matter F adhering to each Fabry-Perot interference filter 1 can be appropriately detected and removed. Therefore, according to this manufacturing method, the same effect as the manufacturing method of the photodetector 10 described above can be obtained.

Further, in the step of obtaining the plurality of light detection devices 10A, the lid substrate layer 940 in which the plurality of openings 94c are formed in advance is provided so that each of the plurality of openings 94c faces each of the plurality of Fabry-Perot interference filters 1. , Joined to the support layer 930. As described above, by using the lid substrate layer 940 in which the plurality of openings 94c are formed in advance, the photodetector 10A in which the openings 94c for incident light are formed in the lid substrate 94 is supported by the lid substrate layer 940 and the lid substrate layer 940. It can be obtained immediately after cutting the layer 930. This eliminates the need for a step of forming an opening 94c in the lid substrate 94 of each photodetector 10A after cutting.

In the wafer 100, a plurality of Fabry-Perot interference filter units 1A serving as a plurality of Fabry-Perot interference filters 1 are provided in the effective area 101. On the other hand, a plurality of dummy filter units 2A are provided in the dummy area 102 along the outer edge 110c of the substrate layer 110 and surrounding the effective area 101, and each dummy filter unit 2A has a first mirror unit 31 facing each other. An intermediate layer 23 is provided between the second mirror portion 32 and the second mirror portion 32. As a result, the strength of the entire wafer 100 is sufficiently ensured. Therefore, the handling of the wafer 100 becomes easy when the above-mentioned inspection method is carried out for each Fabry-Perot interference filter unit 1A. Further, since the wafer 100 is less likely to warp, inspection of each Fabry-Perot interference filter unit 1A and air blow to the Fabry-Pérot interference filter unit 1A in which foreign matter is detected can be performed with high accuracy.

Further, in the method of manufacturing the wafer 100, the gap S is formed in each Fabry-Perot interference filter unit 1A while the plurality of Fabry-Perot interference filter units 1A remain in the state of the wafer 100. As a result, the void S can be formed between the first mirror portion 31 and the second mirror portion 32 with extremely high efficiency as compared with the case where the formation of the void S is performed at the individual chip level. Moreover, in the effective area 101, a portion corresponding to an arbitrary substrate 11 in the substrate layer 110, such as etching of the intermediate layer 230 simultaneously on a plurality of planned removal portions 50 arranged two-dimensionally, and a portion thereof. Since the process proceeds at the same time as the portion corresponding to the surrounding substrate 11 surrounding the substrate layer 110, the in-plane stress bias of the substrate layer 110 can be reduced. Therefore, according to the method for manufacturing the wafer 100, it is possible to obtain the wafer 100 which enables stable mass production of the high quality Fabry-Perot interference filter 1.

Further, the wafer 100 is cut along each line 5 by forming the modified region 7 inside the substrate layer 110 along each line 5 by irradiation with the laser beam L for the following reason. It is extremely effective in manufacturing the Fabry-Perot interference filter 1. That is, since water is not required for cutting the wafer 100 using the laser beam L, the second mirror portion 32 floating on the void S is damaged by water pressure, or water enters the void S and sticks (sticking). The phenomenon that the second mirror portion 32 comes into contact with the first mirror portion 31 and becomes immobile) does not occur. Therefore, cutting the wafer 100 using the laser beam L is extremely effective in manufacturing the Fabry-Perot interference filter 1.
[Modification example]

Although one embodiment of the present invention has been described above, the present invention is not limited to the above-described embodiment. For example, as the material and shape of each configuration, not only the above-mentioned material and shape but also various materials and shapes can be adopted.

As shown in FIG. 14, in the wafer 100, the modified region 7 may be formed inside the substrate layer 110 so as to correspond to the first groove 290. Here, the fact that the modified region 7 corresponds to the first groove 290 means that the modified region 7 overlaps with the first groove 290 when viewed from the opposite direction, and in particular, the modified region 7 or each line 5 It means the state formed along the. As a result, cracks can be extended from the modified region 7 in the thickness direction of the substrate layer 110, and a plurality of Fabry-Perot interference filters 1 can be easily and accurately cut out from the wafer 100. In this case, the expand tape 60 may be attached to the second surface 110b side of the substrate layer 110. At this time, the outer edge portion of the expanded tape 60 attached to the wafer 100 is held by the annular frame. As a result, the wafer 100 can be easily handled even when the modified region 7 is formed inside the substrate layer 110. In the wafer 100 in which the modified region 7 is formed inside the substrate layer 110, cracks may unexpectedly extend from the modified region 7. In the wafer 100, since the plurality of dummy filter portions 2A and the first groove 290 and the second groove 470 are not provided in the pair of areas 102a of the dummy areas 102, the crack extension is stopped by the pair of areas 102a. Will be.

Further, in the step of detecting the foreign matter F and the step of blowing air whose position of the airflow peak is adjusted based on the position of the detected foreign matter F, the operation control (computer control) of the inspection device 500 is performed as in the above embodiment. ) Or manually. For example, the step of detecting the foreign matter F may be executed by the operator visually confirming the foreign matter F adhering to the surface 24a of the second laminated body 24. Further, the step of blowing the air may be performed by manually operating a hand gun type air gun to blow air.

Further, in the photodetector 10A according to the second embodiment, the support 93 has the first substrate 93a, the second substrate 93b, the third substrate 93c, the fourth substrate 93d, and the fifth substrate 93e formed as separate bodies from each other. However, the number of layers of the substrate constituting the support 93 (here, 5 layers as an example) may be less than 5 layers or more than 5 layers. Further, the support 93 may be an integrally formed member. That is, the first substrate 93a, the second substrate 93b, the third substrate 93c, the fourth substrate 93d, and the fifth substrate 93e may be integrally formed. In this case, in the manufacturing process of the photodetector 10A, instead of the support layer 930 described above, the first substrate layer 930a, the second substrate layer 930b, the third substrate layer 930c, the fourth substrate layer 930d, and the fifth substrate described above are used. A support layer in which the layer 930e is integrally formed is used.

Further, in the method for manufacturing a photodetector according to the second embodiment described above, a lid substrate layer in which a plurality of openings 94c are not formed may be used. In this case, after cutting the lid substrate layer and the support layer 930, a photodetector having a lid substrate on which the opening 94c is not formed can be obtained. Then, by forming the opening 94c in the lid substrate of the photodetector thus obtained, the above-mentioned photodetector 10A can be obtained. The person who manufactures the photodetector having the lid substrate on which the opening 94c is not formed and the person who forms the opening 94c in the lid substrate may be the same or different from each other. For example, a photodetector manufactured by using a lid substrate layer in which a plurality of openings 94c are not formed (that is, a photodetector in a state where the openings 94c are not formed in the lid substrate) is shipped and is shipped to the shipping destination. An opening 94c may be formed in the lid substrate of the photodetector.

1 ... Fabric Perot Interference Filter, 1A ... Fabric Perot Interference Filter, 10, 10A ... Photodetector, 11 ... Substrate, 11a ... First Surface, 11b ... Second Surface, 22 ... First Laminate, 24 ... Second Laminate, 24a ... surface, 24b ... through hole, 31 ... first mirror part, 32 ... second mirror part, 71 ... package, 71a, 94c ... opening, 72 ... stem, 73 ... cap, 77,91 ... light detection Vessel, 92 ... SMD package (package), 93 ... support, 94 ... lid substrate, 94c ... opening, 100 ... wafer, 930 ... support layer, 940 ... lid substrate layer, F ... foreign matter, S ... void.

Claims (6)

A method of manufacturing an optical device including a lid substrate, a package having a support bonded to the lid substrate, and a Fabry-Perot interference filter arranged in the package.
In the Fabry-Perot interference filter, a gap is formed between the first mirror portion and the second mirror portion facing each other, so that the distance between the first mirror portion and the second mirror portion facing each other is formed. Is a Fabry-Perot interference filter configured to change with electrostatic force.
The manufacturing method is
The process of preparing a plurality of the Fabry-Perot interference filters, and
A plurality of the Fabry-Pérot interference filters arranged one-dimensionally or two-dimensionally are attached to the support layer that supports the plurality of the Fabry-Pérot interference filters and is to be cut by the plurality of the supports. The first step to support and
A second step of obtaining a plurality of the optical devices connected one-dimensionally or two-dimensionally by joining the lid substrate layer to be cut to the plurality of lid substrates to the support layer after the first step. When,
After the second step, the third step of obtaining the individual optical device by cutting the portion where the lid substrate layer and the support layer are joined.
Prior to the second step, foreign matter adhering to the surface of each of the plurality of Fabry-Perot interference filters is detected, and air whose peak position of the airflow is adjusted based on the position of the detected foreign matter is applied to the surface. And the step of removing the foreign matter from the surface by spraying on
A method of manufacturing an optical device, including. The optical device further comprises a photodetector that detects light transmitted through the Fabry-Perot interference filter in the package.
In the first step, a plurality of the photodetectors provided corresponding to the plurality of Fabry-Perot interference filters are supported by the support layer.
The method for manufacturing an optical device according to claim 1. The optical device further includes a temperature compensating element.
In the first step, a plurality of the temperature compensating elements provided corresponding to the plurality of Fabry-Perot interference filters are supported by the support layer.
The method for manufacturing an optical device according to claim 1 or 2. The lid substrate layer has a light transmitting substrate layer and a light shielding layer.
The light-shielding layer is formed with a plurality of openings provided corresponding to the plurality of Fabry-Perot interference filters.
The method for manufacturing an optical device according to any one of claims 1 to 3. In the step of preparing the plurality of Fabry-Perot interference filters, a wafer in which the plurality of Fabry-Perot interference filters are two-dimensionally connected is prepared.
The method for manufacturing an optical device according to any one of claims 1 to 4. In the step of preparing a plurality of the Fabry-Perot interference filters, a plurality of individualized Fabry-Perot interference filters are prepared.
The method for manufacturing an optical device according to any one of claims 1 to 4.

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