JP5454069B2 - Film forming apparatus, operation method thereof, and electric apparatus - Google Patents

Description

  The present invention relates to a film forming apparatus, an operation method thereof, and an electrical apparatus. In particular, the present invention relates to a film forming apparatus for removing film deposits deposited on an electrode in a film forming apparatus such as plasma CVD, an operation method thereof, and an electric apparatus including a film manufactured using the film forming apparatus.

  In recent years, in the manufacturing process of electric devices such as thin film solar cells, photosensitive drums, and TFT arrays for displays, or electronic components used in electric devices, for example, amorphous silicon films such as p-type, i-type, and n-type, and microcrystal silicon A membrane is actively used. These films are formed on the surface of some member (hereinafter referred to as “substrate”) so that the silicon film is a single layer or a multilayer. For this film forming process, a film forming apparatus such as a plasma CVD method is often used.

FIG. 1 shows a schematic configuration diagram of a film forming apparatus 500 used in a conventional plasma CVD method. In the film forming apparatus 500, a source gas such as monosilane (SiH ₄ ) gas (hereinafter also simply referred to as “silane gas”) is introduced from the gas introduction path 13 into the reduced pressure reaction chamber 4. In the reaction chamber 4, an electrode 2 connected to an RF (high frequency) power supply line 12 is disposed to excite the plasma 17, and a substrate 1 on which film formation is performed so as to face the electrode 2. (Hereinafter referred to as “deposition substrate 1”) is disposed. The film formation substrate 1 is controlled to a temperature suitable for film formation by being heated by the heating head 5 on the back surface. For this purpose, the heating head 5 includes a heater 52 such as a ring heater, for example, and appropriate electric power is supplied to the heater 52.

  As an example, the electrode 2 as described above is provided with a shower plate 22 on a surface 2A (hereinafter referred to as “electrode surface 2A”) of the electrode 2 disposed so as to face the film formation substrate 1 toward the film formation substrate 1. I have. The shower plate 22 has a large number of gas outflow holes 22A that penetrate the shower plate 22 itself. The source gas from the gas introduction path 13 is once expanded in the concave portion 24 inside the electrode 2 and then supplied from the outflow hole 22A to the space on the deposition substrate 1 side. In this way, the film forming apparatus 500 performs the film forming process while ensuring film forming uniformity. The film forming apparatus 500 performs a film forming process while decomposing the source gas by the plasma 17 in an environment in which a certain amount of source gas is supplied and exhausted from the exhaust port 14. When the film forming apparatus 500 is actually operated to perform the film forming process, the film forming substrate 1 is exchanged (in the case of a single wafer substrate) or is transported (in the case of a roll substrate) and is continuously operated.

  While the film forming apparatus 500 is operated to form a silicon film (not shown), the shower plate 22 continues to be exposed to plasma. For this reason, when the film formation process is performed, a considerable amount of silicon deposit 3 (hereinafter referred to as “film formation attached”) is formed on the electrode surface 2A of the electrode 2, particularly on the surface of the shower plate 22 facing the film formation substrate 1. Kimono 3 ”) is formed. When the deposition of the film deposit 3 proceeds to a certain level or more, the film deposit 3 starts to peel from the surface of the shower plate 22. Then, the peeled film deposit 3 becomes granular or dusty film particles 15 and scatters inside the reaction chamber 4. FIG. 1 shows the situation at this time. Further, as the deposition of the deposit 3 progresses, the outflow holes 22A of the shower plates 22 arranged in a large number so as to improve the uniformity are clogged unevenly or disorderly, so that the air flow for supplying the source gas is increased. It becomes uneven. For example, as indicated by an arrow 222 from the shower plate 22 in FIG. 1, there are places where the supply amount of the raw material gas becomes insufficient and where the supply amount becomes excessive. Thus, the uniformity of the film formed on the film formation substrate 1 is lowered.

  Troublesomely, the film particles 15 are mixed into the silicon film being formed on the surface of the film formation substrate 1, the film formation surface 16 is damaged, or the film particles 15 adhere to the surface of the film formation substrate 1. To do. Such a phenomenon causes a reduction in film formation quality. The film particles 15 also adhere to the inner wall of the reaction chamber 4. The film particles 15 adhering to the inner wall of the reaction chamber 4 fly up in the reaction chamber at a timing unintended by the operator, for example, when introducing some gas into the reaction chamber 4. The film quality is degraded.

  In order to avoid such a situation, it is necessary to periodically stop the operation of the film forming apparatus 500 to remove the film deposits 3 on the electrode surface 2A of the electrode 2 including the shower plate 22, that is, to perform a cleaning operation. is there. In a cleaning operation in a conventional film forming apparatus, for example, the reaction chamber 4 is opened, and the film deposits 3 on the surface of the removed shower plate 22 are removed by sandblasting and chemicals. Also, operations such as manually wiping the film particles 15 inside the reaction chamber 4 are generally performed.

  Further, in order to clean the inside of the reaction chamber without opening the film forming apparatus, plasma etching is also performed using a cleaning gas. Also disclosed is a technique for preventing film deposition by introducing a cooling gas into the reaction chamber to cool the electrode. These techniques are disclosed in Patent Document 1, for example.

JP 2007-227501 A

  The above-described conventional cleaning operation is performed as follows as an example. First, the operation of the film forming apparatus is stopped, the heating by the heater 52 is stopped, and the reaction chamber 4 that has been decompressed is returned to atmospheric pressure. Thereafter, the reaction chamber 4 is opened, and the shower plate 22 is removed manually. The film particles 15 inside the reaction chamber 4 are wiped manually. At the same time, the film deposit 3 on the shower plate 22 is removed by sandblasting. The shower plate 22 is further washed with a chemical solution. When these are completed, the washed shower plate 22 is attached again to the inside of the reaction chamber 4. Then, after the reaction chamber 4 is brought into the reduced pressure state again, the heating head 5 is heated by the heater 52. However, such a conventional cleaning operation has a large work load and requires several hours to several tens of hours, so that the operating rate of the film forming apparatus is significantly reduced.

  In the cleaning method by plasma etching using the above-described cleaning gas, a special gas (reactive gas) is used, so that the environmental load is large and the equipment cost is high, and a considerable time is required until the cleaning is completed. In addition, in the cleaning method in which the cooling gas is introduced into the reaction chamber, it is cooled to an unintended portion in the reaction chamber, so that it takes a long time to return the apparatus to the film formation state.

  As described above, the above-described cleaning method requires several hours to several tens of hours for maintenance of the film forming apparatus, and involves a great work load. For this reason, any cleaning method significantly reduces the productivity of the film forming process. The present invention has been made in order to solve at least some of the above-described problems. By reducing the workload for maintenance of the film forming apparatus and improving the operating rate of the film forming apparatus, the film forming apparatus and the This greatly contributes to increasing the production efficiency of products manufactured by the film forming process used.

  In order to solve the above-mentioned problem, the inventors of the present application first analyzed the mechanism by which the film deposit 3 is peeled as described above. Through careful investigation and analysis, the inventors of the present application have found that the film particles 15 from the shower plate 22 of the electrode 2 of the film forming apparatus as described above are formed by the film deposit 3 deposited on the electrode surface 2A of the electrode 2 as an electrode. It was found that it was peeled off from the boundary surface with 2. Moreover, it has been found that the peeling hardly occurs until the film deposit 3 is deposited to a certain degree. That is, peeling of the film deposit 3 often occurs after the deposition has progressed sufficiently. Further, the inventors of the present application have considered that one of the triggering events is a temperature change of the electrode 2 and the film deposit 3. That is, the inventors of the present application speculate that the temperature of the electrode 2 fluctuates for some reason, resulting in peeling at the interface between the electrode 2 and the film deposit 3. By the way, when the film deposit 3 is mainly composed of silicon, the material of the film deposit 3 is brittle. For this reason, in the conventional film forming apparatus, if the film is peeled in a state where stress (thermal stress) due to temperature is applied, the film deposit 3 is scattered as dust or granular film particles 15.

  Therefore, the inventors of the present application have made further studies with the intention of solving the above problems based on the above analysis results. As a result, it has been found that film deposits can be effectively removed by using the principle in reverse.

  That is, as an aspect of the present invention, a reaction chamber capable of depressurization, an electrode portion provided in the reaction chamber and having an electrode surface, and a heating and cooling head provided in the reaction chamber and having a heating and cooling surface A first position where the heating / cooling surface is opposed to the electrode surface across a space, and a second position where the heating / cooling surface is directly or indirectly brought into contact with the electrode surface. And a heating / cooling head that can move between the two, a film forming apparatus that cools the electrode portion by the heating / cooling head at the second position, and peels the film deposits deposited on the electrode portion. Provided.

  In the film forming apparatus described above, the first position is the position of the heating / cooling head when the heating / cooling surface of the heating / cooling head is located between the electrode surface and the heating / cooling head. This is the position of the heating / cooling head when the film processing is performed. The second position is the position of the heating / cooling head when the heating / cooling surface of the heating / cooling head is in direct or indirect contact with the electrode portion. The heating / cooling head at the second position cools the electrode portion and peels the film deposit from the electrode. Here, the timing at which the heating / cooling head takes the second position and the timing at which the heating / cooling head cools the electrodes can be various timings. For example, the heating / cooling head can start cooling the electrode at the same time as the second position, and the heating / cooling head starts cooling after a certain time has elapsed since the second position. Can also be configured.

  In the present invention, an aspect of an operation method of the film forming apparatus is also provided. That is, in a reaction chamber capable of depressurization including a heating / cooling head having a heating / cooling surface and an electrode portion having an electrode surface, the heating / cooling head is opposed to the electrode surface with a space between the heating / cooling surface. Moving the heating / cooling surface from the first position to a second position to directly or indirectly contact the electrode surface; and the electrode section by the heating / cooling head at the second position. The method of operating the film forming apparatus is provided, which includes the step of cooling the film, and thereby peeling the film deposits deposited on the electrode part.

  In the present invention, there is provided an electric device including a film formed by the film forming apparatus included in the above-described aspect or a film formed using the operation method included in the above-described aspect. . Here, the electric device refers to any object that allows electricity to flow. This includes information processing equipment and energy generation equipment. That is, for example, the electrical device here is a component such as a thin-film solar cell, a photosensitive drum, and a display array substrate, and an arbitrary device including these components.

  In the present application, peeling means that physical continuity is lost in an integrated object, resulting in two or more separate objects, even if two objects are in contact with each other If continuity is lost, it is said that they are separated.

  According to any aspect of the present invention, the deposit on the electrode can be easily peeled off in the reaction chamber. For this reason, not only the amount of silicon material itself that can become film particles is reduced, but also the work time for maintenance of the film forming apparatus can be shortened. The amount can be significantly reduced.

It is sectional drawing which shows the schematic structure of the conventional plasma CVD film-forming apparatus. It is explanatory drawing explaining the principle which a film | membrane peels in a certain aspect of this invention. It is sectional drawing which shows the schematic structure of the film-forming apparatus in a certain aspect of this invention. It is explanatory drawing which shows the operation | movement of the maintenance process in the film-forming apparatus of a certain aspect of this invention. It is explanatory drawing which shows the operation | movement of the maintenance process in the film-forming apparatus of a certain aspect of this invention. It is explanatory drawing which shows the structure of the heating-cooling apparatus used for the film-forming apparatus of a certain aspect of this invention. It is a schematic block diagram which shows the structure of the film-forming apparatus in a certain aspect of this invention.

  Hereinafter, embodiments of the present invention will be described. In this description, common parts or elements are denoted by common reference symbols throughout the drawings unless otherwise specified. In the drawings, each element of each embodiment is not necessarily shown in a scale ratio.

  First, the principle by which peeling is realized in each aspect of the present invention will be described. FIG. 2 is an explanatory view for explaining the principle of peeling the film deposit 3 in the embodiment of the present invention. The portion where the film deposit 3 is deposited on the shower plate 22 which is a part of the electrode 2 is shown. It is expanded sectional drawing. The film deposit 3 is deposited and formed while the shower plate 22 of the electrode 2 is heated to a high temperature by the film forming process (FIG. 2A). As deposition proceeds, the film deposit 3 becomes thicker than the film deposited on the film formation substrate 1. Next, the electrode 2 and the shower plate 22 are cooled. At this time, since there is a difference in linear expansion coefficient between the material of the shower plate 22 of the electrode 2 and the material of the film deposition deposit 3, the shower plate 22 contracts more than the film deposition deposit 3 with cooling. To do. Accordingly, when the film is sufficiently cooled, the film deposit 3 cannot follow the contraction of the shower plate 22 (FIG. 2B). As a result, the film deposit 3 is peeled off at the interface between the shower plate 22 and the film deposit 3, that is, the electrode surface of the electrode 2. An embodiment of the present invention that actively uses such a principle will be described in more detail.

<First Embodiment>
FIG. 3 shows a state where the plasma CVD film forming apparatus (also referred to simply as “film forming apparatus” in the present application) 100 according to the first embodiment of the present invention shifts from the film forming process to the maintenance process. It is sectional drawing. 4 and 5 are explanatory diagrams of the operation of the maintenance process of the plasma CVD film forming apparatus 100. FIG. FIG. 6 is an explanatory diagram showing a configuration of the heating / cooling device 6 provided in the plasma CVD film forming apparatus 100.

  As shown in FIG. 3, the plasma CVD film forming apparatus 100 includes a heating / cooling apparatus 6. As shown in FIG. 6, the heating / cooling device 6 has a head portion 62 having a heating / cooling surface 62A on the electrode 2 side, that is, a heating / cooling head, and a flow path 63 therein. . In the flow path 63, the medium 64 supplied from the temperature adjustment device 61 flows from the IN side end 63a to the OUT side end 63b of the flow path 63. The medium 64 plays a main role of heating or cooling the head portion 62 of the heating / cooling device 6. The medium 64 circulates between the flow path of the temperature control device 61 and the flow path 63 of the head portion 62 by a circulation device (not shown) of the temperature control device 61.

  The temperature of the medium 64 is controlled by the temperature adjustment unit 65. For example, a temperature signal indicating the temperature of the medium 64 and a temperature signal indicating the temperature of the head unit 62 are input to the temperature adjustment unit 65. The temperature adjusting unit 65 performs control to heat or cool the medium 64 so that at least one of these temperature signals or a temperature index generated by these signals approaches a set temperature command value. For this medium 64, for example, a known oil can be used. Thus, the heating / cooling device 6 as a whole has a structure in which the heating operation or the cooling operation is switched according to the temperature command value.

  Next, switching operation from the film forming process to the maintenance process in the film forming apparatus 100 using the heating / cooling apparatus 6 having such a configuration will be described. First, when the plasma CVD film forming apparatus 100 is performing a film forming process, that is, when the film forming apparatus 100 is in operation, the film forming substrate 1 is heated by the head unit 62. At this time, a raw material gas such as silane gas is supplied from the gas introduction path 13 into the reaction chamber 4 decompressed by the exhaust from the exhaust port 14. Then, a film forming process is performed on the film forming substrate 1 while the source gas is decomposed by the plasma 17. This source gas is once expanded in the recess 24 inside the electrode 2, and then supplied to the space on the deposition substrate 1 side from the outflow hole 22 </ b> A that penetrates the shower plate 22 itself. When the film forming apparatus 500 is actually operated to perform the film forming process, the film forming substrate 1 is exchanged (in the case of a single wafer substrate) or is transported (in the case of a roll substrate) and is continuously operated.

Here, the film to be formed will be described in more detail as a silicon (Si) film. For example, a Si film is formed on the deposition substrate 1 using, for example, a monosilane (SiH ₄ ) gas as a source gas. This film forming process is performed by placing the film forming substrate 1 in a space secured between the heating / cooling surface 62 </ b> A of the head unit 62 and the shower plate 22 of the electrode 2. For this reason, the head part 62 is controlled to take a position (first position) where the space is provided between the electrode surface 2A and the heating / cooling surface 62A. In the space on the electrode 2 side of the deposition substrate 1, plasma is excited by applying high-frequency power to the source gas supplied from the outflow hole 22 </ b> A through the RF power supply line 12. By such treatment, a silicon (for example, amorphous silicon) film decomposed by the plasma 17 is deposited on the deposition substrate 1. The process described above is performed continuously or intermittently for as long as possible while the deposition substrate 1 is being sent or replaced.

  More specifically, for example, when the film formation substrate 1 is a roll-shaped flexible substrate, the film formation substrate is continuously shifted in the direction perpendicular to the paper surface of FIG. The film forming process is performed while feeding 1. As another example, even if the film formation substrate 1 is a roll-shaped flexible substrate, first, after the film formation process is performed on a certain area in a state where the film formation substrate 1 is stationary, In order to form a film, it is also possible to perform the next film formation process after moving the film formation substrate 1. In either case, an appropriate processing unit can be used. Here, in an example in which a roll-shaped flexible substrate is used, when one roll of film is formed, the reaction chamber may be temporarily opened to replace the roll-shaped substrate. Therefore, it is practically preferable to use the above-mentioned processing unit by replacing the roll-shaped flexible substrate.

  During the film formation process, the film formation substrate 1 is heated by the heating / cooling surface 62A of the heating / cooling device 6 in order to perform film formation. Here, in this case, the temperature of the electrode 2 and the shower plate 22 can reach about 200 ° C. by the heat from the head portion 62 and the heat from the plasma. In addition, a silicon film is deposited as a film deposit 3 on the shower plate 22 of the electrode 2 by the operation of the film forming process of the plasma CVD film forming apparatus 100. For example, the intrinsic stress of the deposited Si film (deposition deposit 3) is about 200 MPa.

  When a certain processing unit described above is completed in the operation process of the film forming apparatus, the film forming substrate 1 for film formation provided between the electrodes 2 is replaced with a dummy substrate 7 (FIG. 3). At this time, the film thickness of the film deposit 3 deposited on the shower plate 22 of the electrode 2 has reached a certain level. This replacement can be set to be performed periodically or after a certain amount of processing has been completed. More specifically, the time when the accumulated operating time exceeds a predetermined time or the time when one roll of film is formed can be used as a suitable processing unit. When the dummy substrate 7 is installed, the heating operation of the heating / cooling device 6 that has been performed for the film forming process is stopped and switched to the cooling operation, so that the head unit 62 of the heating / cooling device 6 is cooled. Is done. Without being limited to the above, the replacement time of the dummy substrate 7 and the switching time from the heating operation to the cooling operation can be appropriately selected.

  When the installation of the dummy substrate 7 and the cooling operation of the heating / cooling device 6 are completed, as shown in FIG. 4, the head portion 62 of the heating / cooling device 6 is advanced toward the electrode 2 on which the film deposition deposit 3 is deposited, The head portion 62 contacts the electrode 2 together with the dummy substrate 7. For this reason, the position of the head unit 62 is controlled so as to take a position (second position) that indirectly contacts the electrode surface 2A of the electrode 2 with the dummy substrate 7 interposed therebetween. Here, the head portion 62 taking the second position may be positioned so as to sandwich the dummy substrate 7 with the electrode 2. For this reason, it is a preferable aspect of the present embodiment that the position of the head unit 62 is controlled so as to be separated from the electrode 2 by the thickness of the dummy substrate 7. Further, it is another preferable aspect of the present embodiment that the head unit 62 is biased by a certain pressing force and is controlled so as to sandwich the dummy substrate 7.

  The heating / cooling device 6 includes a driving device (not shown) for moving the head portion 62 forward and backward in this manner. The movement of the head portion 62 can be performed while maintaining the reduced pressure in the reaction chamber 4. Various known structures can be employed as the structure for this purpose. For example, as shown in FIGS. 3 to 5, when a part of the head part 62 extends outside the wall of the reaction chamber 4, an airtight seal is provided between the part and the wall of the reaction chamber. The head unit 62 can move while maintaining a reduced pressure state. Although not shown in the drawings, as another configuration, if a driving device is arranged in the decompression region 8, it is not necessary to use the seal as described above. In such a state, it is also preferable that the medium 64 from the temperature control device 61 guided to the inside of the reaction chamber 4 is circulated through the inside of the head portion 62 by an appropriate flexible flow path. It is.

In the present embodiment, the dummy substrate sandwiched between the electrode 2 and the head portion 62 can be made of the same material as the film formation substrate 1. In particular, when the dummy substrate is flexible, the degree of adhesion is improved between the electrode surface 2A of the electrode 2 and the heating / cooling surface 62A of the head portion 62, that is, is in thermal contact with the dummy substrate. The effective area can be increased. Therefore, the thermal resistance between the electrode 2 and the head part 62 can be reduced. In addition, the dummy substrate 7 avoids direct contact between the electrode surface 2A of the electrode 2 and the heating / cooling surface 62A of the head portion 62 of the heating / cooling device 6, thereby preventing both surfaces 2A, 62A from being scratched. Can play a protective role. Further, the dummy substrate 7 can serve to prevent the fragments of the film deposit 3 from being scattered in an unintended direction due to peeling.

The electrode 2 is cooled by the cooling operation of the heating and cooling device 6 until it reaches about 140 ° C., for example. In this example, when the temperature of the shower plate 22 of the electrode 2 during film formation is 200 ° C., a cooling operation of about 60 ° C. is performed as a temperature difference. If the shower plate 22 and the film deposit 3 are contracted by causing such a temperature difference, the film deposit 3 can be peeled from the shower plate 22. At this time, for example, if the shower plate 22 is A5052 which is an aluminum alloy, its linear expansion coefficient is 23.8 × 10 ⁻⁶ . On the other hand, since the linear expansion coefficient of the film deposit 3 (Si) is 2.6 × 10 ^−6, it is possible to ensure a difference in contraction amount sufficient for the peeling treatment of the film deposit 3. The deposit 32 peeled off from the electrode surface 2A of the electrode 2 by the cooling operation falls into the collection box 10 (container) arranged immediately below.

  Next, the operation when moving from the maintenance process to the film forming process will be described. After the film deposition deposit 3 is peeled off by the cooling operation shown in FIG. 4, the head part 62 of the heating / cooling device 6 is moved backward again to the first position as shown in FIG. At this time, for example, the head unit 62 switches the temperature adjustment device 61 from the cooling operation to the heating operation by setting the temperature command value to the temperature at the time of film formation. When the head portion 62 is moved backward, the peeled deposit 32 sandwiched between the dummy substrate 7 and the shower plate 22 falls into the collection box 10. The dummy substrate 7 sandwiched between the head portion 62 and the electrode 2 is taken out of the reaction chamber 4 by carrying the substrate, for example. Thereafter, when the deposition substrate 1 to be deposited is set at a predetermined position, the deposition operation is resumed and the deposition apparatus 100 is operated.

  According to the embodiment as described above, the time for stopping the operation is mainly set to a temperature suitable for film formation by the heating / cooling device 6 again after the heating / cooling device 6 starts cooling the electrode 2. It depends on the time required for temperature operation before returning. At this time, for example, a long time such as etching with a cleaning gas is not necessary, and the fragments of the film deposit 3 are not scattered as particles or dust. Therefore, the operation of manually cleaning the inside of the reaction chamber 4 is not required or the frequency thereof is greatly reduced. Furthermore, the need to remove the shower plate 22 after the reaction chamber 4 is opened to the atmosphere and to perform a sandblasting process or a chemical work is eliminated or greatly reduced. For this reason, according to the above-mentioned embodiment, since it becomes possible to reduce maintenance work time significantly, the operation time of the film-forming apparatus can be extended. The peeled deposit 32 in the collection box 10 can be easily collected when the reaction chamber 4 is opened. From the viewpoint of working time and labor, it is worthy to note that the film forming apparatus can be maintained without opening the reaction chamber to the atmosphere as in the prior art.

  In addition to the above-described advantages, in the above-described embodiment, there may be an effect that the replacement frequency of the shower plate 22 can be reduced. Although the actual replacement frequency depends on various conditions, as an example for explanation, the replacement frequency of the conventional shower plate 22 is set once between a unit in which the film forming apparatus is operated and the next unit. Suppose that they need to be replaced. When the film forming apparatus of the above-described embodiment is operated under the conditions corresponding to the previous conditions, only the peeling process for cooling the electrode 2 once by the head unit 62 is performed for each unit of the operation process. Therefore, the replacement of the shower plate 22 can be performed at a much lower frequency, for example, once every 10 units of operation processing.

  Further, as described above, the dummy substrate can be made of the same kind of material as the film formation substrate. First, the fact that such a selection is possible has an advantage. For example, the dummy substrate can be the same substrate as the film formation substrate, that is, the dummy substrate can be a substrate on which no film formation is performed. As a result, it is not necessary to prepare another type of substrate. Although the present embodiment is not particularly limited, for example, when a roll-shaped substrate, that is, a substrate having a continuous belt-like scroll shape is used as the film formation substrate 1, the above-described effects are unique advantages. It becomes. In the film forming process using such a roll-shaped substrate, the end of the substrate is first set so that the film forming apparatus can appropriately wind the film before film forming is performed, or the film forming process is finished. However, in many cases, the film formation of the roll is completed while the end portion of the substrate is set. That is, the end of the roll substrate before and after the product target portion of the roll substrate is not subjected to the film forming process as a product, although the film forming process is not planned. It may be disposed between the electrode 2 and the head unit 6 before the start or after the film formation process is completed. Such a part is called a roll end. That is, if the dummy substrate is made of the same material as the film formation substrate as described above, the roll end portion of the roll-shaped substrate can be used as the dummy substrate. Then, for example, after performing the film forming process for one roll, the roll end appearing at the end of the roll can be used as a dummy substrate for the peeling process of the above embodiment.

  In addition, although the aluminum alloy was demonstrated to the example about the raw material of the above-mentioned shower board 22, this material can use stainless steel etc. for others. The shower plate 22 is preferably made of a conductive material such as metal because of demands on the film forming process. On the other hand, in order to cause peeling by utilizing the difference in thermal shrinkage, that is, the difference in linear expansion coefficient as in the present invention, in comparison with a film formed of the same material as the film deposition deposit, for example, a silicon film, The shower plate 22 is preferably made of a material having a large difference in linear expansion coefficient. Actually, many metal materials suitable for the above-described film forming process have a larger linear expansion coefficient than silicon, and therefore often satisfy this condition. That is, the peeling treatment as in the present embodiment does not involve any particular difficulty in selecting the electrode and film materials.

<Variation 1 of the first embodiment>
Still other modifications can be made to each embodiment of the present invention.

  First, based on the above-described principle of the present invention, it is possible to realize a film forming apparatus configured to form a film not only on the above-described form but also on a horizontal film-forming substrate. Here, “horizontal” refers to an arbitrary plane having, as a normal line, a direction that generally faces vertically upward or downward. A film forming apparatus 200 for forming a film on such a horizontal film forming substrate can be configured as shown in FIG. 7, for example. The film forming apparatus 200 is configured such that the film forming substrate is oriented horizontally when the film forming apparatus 200 is installed.

  Even if the film forming apparatus 200 is employed, the film deposit 3 deposited on the electrode 2 can be forcibly separated by the heating / cooling apparatus, that is, utilizing the difference in thermal shrinkage. In that case, the present embodiment can be further implemented by arranging several electrodes 2. That is, one is a configuration in which the electrode 2 is disposed above a film formation substrate (not shown) and the film formation substrate or the dummy substrate 7 is disposed below the film formation substrate (FIG. 7). In such a case, the head portion 62 is lowered to place the film formation substrate for film formation, and the head portion 62 on which the dummy substrate 7 is placed is raised to clean the electrode 2 or the like. The shower plate 22 is cooled. In this film forming apparatus 200, unlike the film forming apparatus 100, a collection box (FIG. 3) cannot be used. In the film forming apparatus 200, the peeled deposit 32 is placed on the dummy substrate 7. For this reason, by collecting the dummy substrate 7, it is possible to appropriately recover the peeled deposit 32.

  The other is a configuration in which the electrode 2 is disposed below a film formation substrate (not shown) and the film formation substrate or the dummy substrate 7 is located above (not shown). In such a case, for film formation, the film formation substrate is held by an appropriate holder, and film formation is performed on the lower surface thereof. In these film forming apparatuses, unlike the film forming apparatus 100, the collection box (FIG. 3) cannot be used. In the film forming apparatus 200 of FIG. 7, the peeled deposit 32 is placed on the dummy substrate 7. For this reason, by collecting the dummy substrate 7, it is possible to appropriately recover the peeled deposit 32. In addition, in a film forming apparatus that forms a film on a mask (not shown), the peeled deposit is placed on the electrode surface of the electrode, so that scattering in the reaction chamber can be prevented. In these modified examples, the peeled deposit 32 on the dummy substrate or the peeled deposit on the electrode surface can be collected by other means such as an adhesive tape.

<Modification 2 of the first embodiment>
As another modified example, in each embodiment of the present invention and the modified example thereof, the dummy substrate is preferably a flexible substrate (for example, a known resin substrate). Here, as described above, when film formation is performed using, for example, a roll-shaped substrate, it is preferable that the substrate has flexibility enough to be wound in a roll shape, that is, flexibility. is there. As such an example, a film-like substrate can be adopted. Thus, the reason why the substrate having flexibility and flexibility is preferable is due to the state of the surface of the shower plate 22. On the surface of the shower plate 22, microscopic unevenness is generated by sandblasting or the like. The presence of such irregularities has the effect of preventing biting of the film deposit 3 and preventing it from being inadvertently peeled off. On the other hand, when the head portion 62 is pressed against such a shower plate 22 and heat is taken away, the unevenness reduces the contact area and increases the thermal resistance. Therefore, when a dummy substrate having flexibility as described above is used, it is possible to increase the contact area with respect to the unevenness of the shower plate 22 and reduce the thermal resistance. As a preferable dummy substrate having flexibility, there is a substrate that can be recessed according to the shape of at least a part of the projections and depressions of the shower plate 22. Specifically, for example, a known flexible substrate such as a resin substrate or a resin film substrate is preferable as the dummy substrate of this embodiment because it has such properties.

<Modification 3 of the first embodiment>
Further, as in the case of using a flexible substrate, other forms that can appropriately deal with the unevenness of the electrode surface 2A surface of the electrode 2 (shower plate 22) are also included in the modified example of the present embodiment. That is, the structure which raises the heat conductivity of the clearance gap which arises by an unevenness | corrugation using the gas introduce | transduced in a reaction chamber in the case of cooling is also a part of embodiment of this invention. The optimum type of gas for such a configuration is hydrogen. This is because hydrogen is the gas with the highest thermal conductivity. Moreover, a normal silicon-based film is, for example, a hydrogenated amorphous silicon film or the like, and hydrogen is often used for film formation processing. For this reason, special equipment for introducing hydrogen into the reaction chamber is usually unnecessary, and this embodiment also leads to high practicality from this point.

<Modification 4 of the first embodiment>
In addition, as another modification, it is also preferable to use a metal thin plate or foil for the dummy substrate. An example of such a dummy substrate is an aluminum thin plate. Also in this case, the thermal resistance between the head part 62 and the shower plate 22 of the electrode 2 can be lowered, and the temperature of the electrode 2 and the film 3 can be lowered rapidly.

<Modification 5 of the first embodiment>
In the above-described film forming apparatus, for example, when a thin film solar cell is manufactured using a roll-shaped substrate, three silicon layers, that is, a p-layer, an i-layer, and an n-layer silicon layer are formed once. A film forming apparatus having three reaction chambers may be used so that the film can be formed by passage. In such a case, the present invention can be applied. In this case, in the three reaction chambers for the p layer, the i layer, and the n layer, dummy substrates are simultaneously prepared for all, and the electrode (shower plate) is cooled by the head portion, thereby forming a film on the electrode. It is preferable to remove the deposit. Thereby, there is an advantage that it is not necessary to secure the maintenance time by the number of layers.

Incidentally, in the embodiment and its modifications described above, mainly monosilane (SiH ₄₎ has been described as being deposited silicon as a raw material gas, using disilane (Si 2 _{H 6)} or hydrogenated silane-containing gas such as In addition, the same effects as those of the above-described embodiments can be obtained. As described above, modifications that exist within the scope of the present invention including other combinations of the embodiments are also included in the scope of the claims.

  The present invention greatly contributes to increasing the productivity of the film forming process by greatly reducing the workload of maintenance of the film forming apparatus.

1 Substrate (deposition substrate)
DESCRIPTION OF SYMBOLS 2 Electrode 2A Electrode surface 3 Deposition deposit 4 Reaction chamber 5 Heating head 6 Heating / cooling device 7 Dummy substrate 8 Depressurization area 10 Recovery box 12 RF power supply line 13 Gas introduction path 14 Exhaust port 15 Film particle 16 Deposition surface 17 Plasma 22 Shower plate 22A Outflow hole 32 Deposited material 52 Heater 61 Temperature control device 62 Head (heating / cooling head)
62A Heating / cooling surface 63 Flow path 63a IN side end 63b OUT side end 64 Medium 65 Temperature adjustment unit 100, 200, 500 Film forming apparatus

Claims (19)

A reaction chamber capable of depressurization;
An electrode part provided inside the reaction chamber and having an electrode surface;
A first position provided inside the reaction chamber, having a heating / cooling surface and facing the heating / cooling surface to the electrode surface across a space; and the heating / cooling surface directly or indirectly A heating / cooling head movable under reduced pressure of the reaction chamber between a second position to be brought into contact with the electrode surface,
When the heating / cooling head is in the first position under reduced pressure in the reaction chamber, the source gas introduced into the space on the film formation substrate disposed in the vicinity of the heating / cooling head in the space When film formation is performed and the heating / cooling head is in the second position under reduced pressure in the reaction chamber , the heating / cooling surface directly or indirectly contacts the electrode surface of the electrode portion. Te by cooling the electrode surface, the film forming device for peeling a film deposit deposited on the electrode surface of the electrode portion. The film forming apparatus according to claim 1, wherein the film is heated when the heating / cooling head is in the first position. The film forming apparatus according to claim 1, wherein the heating / cooling head includes a flow path for allowing a medium for heating and cooling to flow from an external temperature control device. 4. The film forming apparatus according to claim 1, wherein the second position is a position where a dummy substrate is sandwiched between the heating and cooling surface of the heating and cooling head and the electrode surface. The heating / cooling head is configured to heat a substrate on which a film forming process is performed in the space when the heating / cooling head is at the first position, and when the heating / cooling head is at the second position, The film forming apparatus according to claim 4, wherein the electrode unit is cooled with the dummy substrate interposed between the electrode and the surface. The electrode surface has irregularities;
The film forming apparatus according to claim 4, wherein the dummy substrate is a substrate made of a flexible material that can be recessed according to the shape of at least a part of the protrusions of the unevenness. The electrode unit, the film forming apparatus according to any preceding claim wherein the electrode surface when the film forming apparatus is installed that has become vertically 1 to claim 6. The film formation apparatus according to claim 7 , wherein the reaction chamber includes a container that receives a film formation deposit separated from the electrode portion. The electrode unit, the film forming apparatus according to any preceding claim wherein the electrode surface when the film forming apparatus is installed that has become horizontal 1 to claim 6. 2. The reaction chamber includes a gas introduction path for supplying gas, and hydrogen gas is supplied from the gas introduction path when the heating / cooling head is in the second position. The film forming apparatus according to claim 9 . An electrode portion having a heating cooling head and the electrode surface having a heating and cooling surfaces under a reduced pressure of evacuable reaction chamber provided therein, first to be opposed to the electrode surface across a space in the front Symbol heating the cooling surface When the heating / cooling head is in position , forming a film with a source gas introduced into the space on a deposition substrate disposed in the vicinity of the heating / cooling head in the space;
Moving the heating / cooling head from the first position to a second position where the heating / cooling surface directly or indirectly contacts the electrode surface;
Cooling the electrode surface by directly or indirectly contacting the electrode surface of the electrode portion with the heating / cooling surface of the heating / cooling head in the second position under reduced pressure in the reaction chamber; A method of operating a film forming apparatus, comprising: peeling the film deposits deposited on the electrode surface of the electrode part by cooling the electrode part. Moving the heating and cooling head to the first position;
The method according to claim 11 , further comprising: heating the heating / cooling head at the first position. The operation method of the film forming apparatus according to claim 11 or 12 , wherein the heating / cooling head is heated or cooled by flowing a medium from an external temperature control device through a flow path provided in the heating / cooling head. The second position, the operation method of the film formation apparatus according to any one of claims 11 to 13 is a position sandwiching the dummy substrate between said heating and cooling surface and the electrode surface of the heating and cooling head . By the first of the heating and cooling head in the position further comprises the step of heating the film-forming board in the space,
The operation of the film forming apparatus according to claim 14 , wherein in the cooling step, the heating / cooling head in the second position cools the electrode by sandwiching the dummy substrate between the electrode surface. Method. The electrode has irregularities;
The dummy substrate, a method of operating a deposition system as claimed in claim 14 or claim 15 which is a substrate made of a material with a flexibility to be dented depending on the shape of at least a portion of the convex portion of the concavo-convex. The operation method of the film forming apparatus according to claim 11 , wherein the cooling includes a step of supplying hydrogen gas from a gas introduction path to the reaction chamber. Before the step of moving the heating / cooling head to the second position, the method further includes the step of cooling the heating / cooling head itself by flowing the medium from the temperature control device.
An operation method of the film forming apparatus according to claim 13. Film has been formed by a film forming apparatus according to claim 1, or an electric device comprising a membrane which is formed by a method of operating a deposition system as claimed in claim 11.

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