JP2007311417A - Thin film manufacturing apparatus and thin film manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress the inclination of a contact surface of a ground electrode without increasing the plate thickness of a wall, even if distortion occurs on the wall due to a difference in pressure between the outside and a film-forming vacuum chamber. <P>SOLUTION: The communication hole of a fixed body 31 that is formed at the distorted center of a wall 15 due to a difference in pressure between a film-forming vacuum chamber 13 and the outside is concentrically positioned at the through-hole of the wall 15, and a supporting body 33 is driven along a rail 34 engaged with a guide 32 that includes two pairs of opposing reference surfaces vertical to the flat face of the fixed body 31. Thus, a flexible substrate 1 is stuck to the end face of a frame 54 while expanding and contracting an elastic body 35, forming a film forming chamber 5. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a thin film manufacturing apparatus and a thin film manufacturing method, and is particularly suitable when applied to a method for manufacturing a thin film photoelectric conversion element.

  As a method for producing a thin film photoelectric conversion element with high productivity, each layer including a photoelectric conversion layer mainly composed of a-Si is formed on a flexible substrate made of a long polymer material or a metal such as stainless steel. There is a way to do it. Here, as a method of forming a plurality of layers on a long flexible substrate, a roll-to-roll method of forming a film on a flexible substrate moving in each film formation chamber, and a stop in the film formation chamber are used. There is a stepping roll method in which after forming a film on a flexible substrate, the flexible substrate portion after film formation is sent out of the film formation chamber.

  In this type of conventional film forming apparatus, the transfer is performed with the flexible substrate surface horizontal, but in order to save the installation space of the apparatus, a method of transferring the substrate with the flexible substrate surface vertical has been proposed. ing. Furthermore, in order to increase the film formation efficiency in one thin film photoelectric conversion element manufacturing apparatus, it is also known that a plurality of flexible substrates are transported in parallel and formed on each flexible substrate surface. Yes.

3 is a plan sectional view showing a schematic configuration of a conventional thin film manufacturing apparatus, FIG. 4 is an enlarged sectional view showing a schematic configuration of a film forming chamber portion during film formation of the thin film manufacturing apparatus of FIG. It is sectional drawing which expands and shows schematic structure of the film-forming chamber part at the time of board | substrate conveyance of this thin film manufacturing apparatus.
3 and 4, the thin film manufacturing apparatus is provided with a feeding chamber 11, a preliminary vacuum chamber 12, a film forming vacuum chamber 13, and a winding chamber. In the feed chamber 11, two carry-in rolls 2 are accommodated, and in the take-up chamber 14, two carry-out rolls 3 are accommodated. Here, the film forming vacuum chamber 13 is covered with a wall 15 that isolates the inside from the outside air, and a high voltage electrode 21 and a ground electrode 22 are provided in the film forming vacuum chamber 13. Here, one high voltage electrode 21 is provided for each flexible substrate 11, and a ground electrode 22 is disposed opposite to the high voltage electrode 21. The ground electrode 22 has a built-in heater 23 for heating the flexible substrate 11.

  An actuator 24 for driving the ground electrode 22 is provided outside the wall 15 of the film forming vacuum chamber 13. Here, the high voltage electrode 21 has a lid shape, and the seal block 8 is provided on the end face of the high voltage electrode 21. Then, the actuator 24 drives the ground electrode 22 to bring the flexible substrate 1 into close contact with the end face of the high voltage electrode 21 through the seal block 8, thereby forming the film forming chamber 5 that can be kept airtight. be able to.

  The back side of the high voltage electrode 21 is connected via an exhaust block 9 made of an insulating material, and a single vacuum exhaust port 72 is provided for the two film forming chambers 5. The exhaust block 9 is in close contact with the high voltage electrode 21 through the sealing material 91 and is connected to the exhaust system through the exhaust port 72 opened in the exhaust block 9 and the opening 25 on the back surface of the high voltage electrode 21. As a result, the respective film forming chambers 5 can be collectively maintained at the film forming pressure.

  Then, the flexible substrate 1 drawn out from the carry-in roll 2 is transferred to the film forming vacuum chamber 13 through the preliminary vacuum chamber 12 and temporarily stopped while being held between the high voltage electrode 21 and the ground electrode 22. Is done. When the flexible substrate 1 is held between the high voltage electrode 21 and the ground electrode 22, the actuator 24 drives the ground electrode 22, so that the end face of the high voltage electrode 21 is interposed via the seal block 8. Then, the flexible substrate 1 is brought into close contact with each other to form the film formation chamber 5. Then, while evacuating the film forming chamber 5 through the exhaust port 72, a reaction gas for forming an a-Si-based thin film is introduced into the film forming chamber 5, and the high voltage electrode 21, the ground electrode 22, By applying a voltage between them, plasma 6 is generated in the film forming chamber 5 and an a-Si thin film is formed on the surface of the flexible substrate 1 in the film forming chamber 5 by plasma CVD. . Since the two film forming chambers 5 are electrically insulated by the exhaust block 9, the plasma 6 can be controlled for each film forming chamber 5.

  Then, after the film formation on the surface of the flexible substrate 1 is completed, the ground electrode 22 is restrained by the ground electrode 22 by moving the ground electrode 22 up and down by several tens of millimeters as indicated by the arrow 41 by the actuator 24. The flexible substrate 1 is released. Then, the flexible substrate 1 can be transported in the direction of the arrow 42 without being brought into contact with the seal block 8 and the seal material 91, and taken up by the carry-out roll 3 in the take-up chamber 14.

  Here, in order to stably form an a-Si-based thin film on the surface of the flexible substrate 1, the flexible substrate 1 is brought into close contact with the end surface of the high voltage electrode 21 via the seal block 8. Therefore, it is necessary to maintain the airtightness of the film forming chamber 5 and prevent the reaction gas introduced into the film forming chamber 5 from leaking out. For this reason, in order to obtain the airtight performance of the film formation chamber 5 necessary for film formation, the surface alignment of the ground electrode 22 is performed when the film formation vacuum chamber 13 is opened to the atmosphere.

Further, for example, in Patent Document 1, it is possible to prevent the film quality from becoming non-uniform due to a change in the state of the magnetic field with respect to the substrate surface for increasing the density of plasma generated by glow discharge, and to enable large-area sputtering film formation. In order to achieve this, a method is disclosed in which an anode and a magnet facing a part of a target serving as a cathode are reciprocated together so as to be movable on a film formation surface.
Japanese Patent Laid-Open No. 9-3645

However, in order to cope with an increase in area such that the width of the flexible substrate 1 exceeds 1 mm, the wall body 15 that covers the film-forming vacuum chamber 13 needs to be relatively enlarged accordingly. And the distortion of the wall 15 due to the pressure difference between the outside and the film forming vacuum chamber 13 also increases.
FIG. 5 is a perspective view showing an aspect of distortion of the wall body 15 due to a pressure difference between the outside and the film forming vacuum chamber.
In FIG. 5, when a pressure difference between the outside and the film forming vacuum chamber 13 occurs, distortion occurs concentrically with the center of the wall 15 as the maximum value.

  Here, in order to obtain the airtight performance of the film forming chamber 5, in the method of performing the surface matching of the ground electrode 22 when the atmosphere is opened to the atmosphere, the fixing point for fixing the ground electrode 22 to the wall body 15 is the maximum distortion point of the wall body 15. Therefore, when the distortion of the wall 15 increases, the adjustment surface of the ground electrode 22 is inclined, and the film forming chamber 5 cannot be kept airtight. For this reason, in order to obtain the airtight performance of the film forming chamber 5, it is necessary to adjust the film forming vacuum chamber 13 in a vacuum state, and it is necessary to separate the outside from the vacuum. There was a problem that it was difficult to meet each other.

On the other hand, in order to reduce the distortion of the wall body 15 due to the pressure difference between the external environment and the film forming vacuum chamber 13, there is a method of increasing the plate thickness of the wall body 15 or performing reinforcement by a rib structure.
However, this method not only increases the size and weight of the thin film manufacturing apparatus, but also increases the cost of the thin film manufacturing apparatus, and it is necessary to reinforce around the building floor and the construction cost is high. There was a problem of becoming.
Therefore, an object of the present invention is to provide a contact surface of the ground electrode without increasing the thickness of the wall body even when the wall body is distorted due to a pressure difference between the outside world and the film forming vacuum chamber. It is providing the thin film manufacturing apparatus and thin film manufacturing method which can suppress inclination of this.

  In order to solve the above-described problem, according to the thin film manufacturing apparatus according to claim 1, a film forming vacuum chamber isolated from the outside by a wall body, and a flexible substrate is transferred to the film forming vacuum chamber. A transporting means, a sandwiching member that forms a film forming chamber in the film forming vacuum chamber by sandwiching a film forming surface of the flexible substrate in a lid shape, and a film forming surface of the flexible substrate The actuator for driving the clamping member and the wall member at a position substantially symmetric with respect to the strain center of the wall body caused by a pressure difference between the film forming vacuum chamber and the outside. And supporting means for supporting the above.

  According to the thin film manufacturing apparatus of claim 2, a film forming vacuum chamber isolated from the outside by a wall, a transfer means for transferring a flexible substrate to the film forming vacuum chamber, A sandwiching member for forming a deposition chamber in the deposition vacuum chamber by sandwiching the deposition surface of the flexible substrate in a lid shape, and driving the sandwiching member so that the deposition surface of the flexible substrate is sandwiched A fixed body in which a hole communicating with the film forming vacuum chamber through a strain center of the wall body caused by a pressure difference between the film forming vacuum chamber and the outside is formed, and a strain center of the wall body The guide member constituting two pairs of opposing reference planes perpendicular to the plane of the fixed body at a position that is substantially point-symmetric with respect to the fixed body, and the holding member while maintaining parallelism between the opposing surfaces of the holding member A support surface to be gripped and a film formation surface of the flexible substrate that is fitted into a reference surface of the guide body A rail for guiding the support so as to be sandwiched by the clamping members, characterized by comprising a stretchable elastic member to the movable said support guiding direction by the rail.

  According to the thin film manufacturing method of claim 3, the step of transporting the flexible substrate to the film forming vacuum chamber isolated from the outside by the wall, and the pressure between the film forming vacuum chamber and the outside By driving the clamping member so that the film formation surface of the flexible substrate is sandwiched in a lid shape while supporting at a position that is substantially point-symmetric with respect to the strain center of the wall body due to the difference, Forming a film formation chamber in the film formation vacuum chamber, and generating plasma in the film formation chamber while introducing a reactive gas into the film formation chamber, thereby forming a film on the film formation surface of the flexible substrate; And a step of forming a film.

  As described above, according to the present invention, while supporting the clamping member at a position that is point-symmetric with respect to the strain center of the wall due to the pressure difference between the vacuum chamber for film formation and the outside, A film formation chamber can be formed in the vacuum chamber. Therefore, even when the wall body is distorted due to the pressure difference between the outside and the film forming vacuum chamber, the clamping member can be supported so that the inclination of the contact surface of the clamping member is canceled out. Even when the flexible substrate has a large area exceeding 1 mm, it is possible to maintain the airtightness of the film formation chamber without increasing the wall thickness. Therefore, deterioration of the film quality of the photoelectric conversion layer formed on the flexible substrate can be suppressed while suppressing an increase in cost.

Hereinafter, a thin film manufacturing apparatus according to an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a plan sectional view showing a schematic configuration of a thin film manufacturing apparatus according to an embodiment of the present invention, and FIG. 2 is a transverse sectional view taken along the line AA ′ of FIG.
1 and 2, the thin film manufacturing apparatus 100 is provided with a feeding chamber 11, a film forming vacuum chamber 13, and a winding chamber 14. In the feed chamber 11, two carry-in rolls 2 are accommodated, and in the take-up chamber 14, two carry-out rolls 3 are accommodated. Here, the film forming vacuum chamber 13 is covered with a wall 15 that isolates the inside from the outside air, and a high voltage electrode 21 and a ground electrode 22 are provided in the film forming vacuum chamber 13. Here, one high voltage electrode 21 is provided for each flexible substrate 11, and a ground electrode 22 is disposed opposite to the high voltage electrode 21.

  The back side of the high voltage electrode 21 is connected via an exhaust block 9 made of an insulating material, and each exhaust block 9 is provided with a vacuum exhaust port 72. In addition, a conductive frame 54 is fixed to the high voltage electrode 21 with a spacing member 53 having both electrical insulation and sealing properties by screwing, and the exhaust block 9 and the high voltage electrode 21 are surrounded by a screw. A conductive shield block 57 having a T-shaped cross section is disposed and fixed to the frame body 54 with screws.

  Then, by connecting the shield block 57 to the wall body 15 fixed to the ground potential, the frame body 54 can be grounded, and the high voltage electrode is formed by the shield block 57 and the frame body 54 fixed to the ground potential. By surrounding 21, noise caused by the applied voltage of the high voltage electrode 21 in the other film forming chamber 5 can be shielded. In addition, a power feeding body 60 is inserted into the shield block 57, and a protruding portion 21a is formed at the center of the high voltage electrode 21, and the high voltage electrode 21 is connected to one end of the power feeding body 60 through the protruding portion 21a. It is connected.

  The ground electrode 22 includes a heater 23 that heats the flexible substrate 1 and a thermocouple 25 that measures the temperature of the flexible substrate 1. The ground electrode 22 is parallel to the contact surface of the frame 54. It is held by the support 33 so as to be maintained. Here, the support body 33 can be comprised from electroconductive members, such as aluminum, for example, and can be made into the container shape which can screw the ground electrode 22 inside. The support 33 is inserted into the film-forming vacuum chamber 13, and a sealing material 331 is disposed on the end surface in contact with the flexible substrate 1.

  Further, a fixed body 31 is installed on the outer surface of the wall body 15, and a communication hole communicating with the film forming vacuum chamber 13 through the through hole of the wall body 15 is formed in the fixed body 31. Here, the through hole of the wall body 15 and the communication hole of the fixing body 31 can be formed so as to pass through the strain center of the wall body 15 caused by the pressure difference between the film forming vacuum chamber 13 and the outside. Then, the communication hole of the fixing body 31 is concentrically aligned with the through hole of the wall body 15, and is screwed to the wall body 15 so as to be kept airtight with the film forming vacuum chamber 13 through the sealing material 311. can do.

  Further, on the fixed body 31, guide bodies 32 constituting two pairs of opposing reference surfaces perpendicular to the plane of the fixed body 31 are provided, and can be fixed to the fixed body 31 by screwing. Here, the reference surface of the guide body 32 can be disposed at a position that is substantially point-symmetric with respect to the strain center of the wall body 15. For example, the reference surface of the guide body 32 can be equally divided with respect to the strain center of the wall body 15 and arranged concentrically with respect to the strain center of the wall body 15.

Further, a rail 34 is provided on the fixed body 31 to guide the support body 33 so that the film formation surface of the flexible substrate 1 is sandwiched by the ground electrode 22 so as to be fitted to the reference surface of the guide body 32. An extendable / contractible body 35 that moves the support 33 in the direction of guide by the rail 34 is provided.
Here, the rail 34 includes a movable member and a fixed member, and a groove guide mechanism can be provided between the movable member and the fixed member so that the movable member can be translated in a straight line. The movable member is fixed to the support 33 by screwing, and the fixed member can be fitted to the reference surface of the guide body 32.

In addition, for example, a spring member made of stainless steel or the like can be used as the stretchable body 35, and the stretchable body 35 can be formed into a stretchable cylindrical shape that can be inserted through the support 33. And the edge part of the expansion-contraction body 35 can be fixed to the fixing body 31 and the support body 33 through the sealing materials 351 and 352, respectively.
Further, an actuator 24 for driving the support 33 is provided outside the wall 15 of the film forming vacuum chamber 13. Then, the actuator 24 can form the film forming chamber 5 that can be kept airtight by driving the support 33 and bringing the flexible substrate 1 into close contact with the end face of the frame body 54.

The exhaust block 9 is in close contact with the high voltage electrode 21 and is connected to the exhaust system through an exhaust port 72 opened in the exhaust block 9 so that the film forming chambers 5 are collectively maintained at the film forming pressure. be able to.
In the thin film manufacturing apparatus 100, the two rows of flexible substrates 1 drawn from the feed chamber 11 are transported in parallel to the film forming vacuum chamber 13, and the flexible substrate 1 is temporarily stopped to form the film forming chamber. 5 is formed, and then a film is formed on the film formation surface of the flexible substrate 1 by plasma CVD. The flexible substrate 1 is released and transported to the take-up chamber 14, so that a stepping roll method is used. The film can be formed by

  That is, the flexible substrate 1 drawn out from the carry-in roll 2 is transported to the film forming vacuum chamber 13 and is temporarily stopped while being held between the high voltage electrode 21 and the ground electrode 22. When the flexible substrate 1 is held between the high-voltage electrode 21 and the ground electrode 22, the actuator 24 drives the support body 33 along the rail 34 to expand and contract the expansion / contraction body 35. The flexible substrate 1 is brought into close contact with the end face of the frame body 54 to form the film forming chamber 5. Accordingly, the flexible substrate 1 can be sandwiched by moving the ground electrode 22 gripped by the support body 33 without falling down or tilting with good rectilinearity while maintaining airtightness with the outside world.

  Here, the through hole of the wall body 15 and the communication hole of the fixed body 31 are formed so as to pass through the strain center of the wall body 15 due to the pressure difference between the film forming vacuum chamber 13 and the outside world. Even when the wall 15 is distorted due to a pressure difference with the film forming vacuum chamber 13, the fixed body 31, the support 33, and the telescopic body 35 are moved in the same direction as the curved distortion of the wall 15. It can be moved, and it is possible to maintain the surface alignment accuracy with the contact surface of the support 33 adjusted when the atmosphere is released, so that the airtightness of the film forming chamber 5 can be kept good.

  When the film forming chamber 5 is formed in the film forming vacuum chamber 13, a reaction gas for forming an a-Si-based thin film is generated while exhausting the film forming chamber 5 through the exhaust port 72. By introducing the film into the film forming chamber 5 and applying a voltage between the high voltage electrode 21 and the ground electrode 22, plasma is generated in the film forming chamber 5, and the inside of the film forming chamber 5 can be formed by plasma CVD. An a-Si thin film is formed on the surface of the flexible substrate 1.

After the film formation on the surface of the flexible substrate 1 is completed, the flexible substrate 1 held by the support 33 is moved by moving the support 33 up and down by the actuator 24 by the actuator 24. And the flexible substrate 1 can be conveyed and taken up by the carry-out roll 3 in the take-up chamber 14.
As a result, the ground electrode 22 is supported in a position symmetric with respect to the strain center of the wall 15 caused by the pressure difference between the film forming vacuum chamber 13 and the outside, and the film forming vacuum chamber 13 is formed. The film chamber 5 can be formed.

  Therefore, the ground electrode 22 is supported so that the inclination of the contact surface of the ground electrode 22 is canceled even when the wall 15 is distorted due to the pressure difference between the outside and the film forming vacuum chamber 13. Even when the area of the flexible substrate 1 is increased so that the width of the flexible substrate 1 exceeds 1 mm, the airtightness of the film forming chamber 5 is maintained without increasing the thickness of the wall 15. Therefore, it is possible to suppress deterioration in film quality of the photoelectric conversion layer formed on the flexible substrate 1 while suppressing an increase in cost.

  The thin film manufacturing apparatus of the present invention can be suitably used for a manufacturing method of a thin film photoelectric conversion element such as a-Si, and in particular, a thin film element in which a plurality of layers are formed on a long flexible substrate. It can be widely used in manufacturing methods.

It is a plane sectional view showing a schematic structure of a thin film manufacturing device concerning one embodiment of the present invention. It is the cross-sectional view cut | disconnected by the AA 'line of FIG. It is a plane sectional view showing a schematic structure of a conventional thin film manufacturing apparatus. 3 is an enlarged cross-sectional view showing a schematic configuration of a film forming chamber portion during film formation of the thin film manufacturing apparatus in FIG. 3, and a cross-sectional view showing an enlarged schematic configuration of a film forming chamber portion during substrate transfer in the thin film manufacturing apparatus of FIG. FIG. It is a perspective view which shows the aspect of the wall body distortion resulting from the pressure difference of the external field and the vacuum chamber for film-forming.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Portable board | substrate 2 Carry-in roll 3 Carry-out roll 5 Film-forming chamber 9 Exhaust member 11 Feed chamber 13 Film-forming vacuum chamber 14 Wind-up chamber 15 Wall body 31 Fixed body 52, 311, 331, 351, 352 Sealing material 32 Guide body 33 Support body 34 Rail 35 Stretchable body 21 High voltage electrode 21a Protruding portion 22 Ground electrode 23 Heater 24 Actuator 53 Spacing material 54 Frame body 57 Shield block 60 Power supply body 70 Exhaust port 100 Thin film manufacturing apparatus 25 Thermocouple

Claims (3)

A vacuum chamber for film formation separated from the outside by a wall,
Transport means for transporting the flexible substrate to the vacuum chamber for film formation;
A sandwiching member that forms a film forming chamber in the film forming vacuum chamber by sandwiching the film forming surface of the flexible substrate in a lid shape;
An actuator for driving the clamping member so that the film-forming surface of the flexible substrate is sandwiched;
Support means for supporting the clamping member on the wall body at a position that is substantially point-symmetric with respect to the strain center of the wall body caused by a pressure difference between the film forming vacuum chamber and the outside. A thin film manufacturing apparatus. A vacuum chamber for film formation separated from the outside by a wall,
Transport means for transporting the flexible substrate to the vacuum chamber for film formation;
A sandwiching member that forms a film forming chamber in the film forming vacuum chamber by sandwiching the film forming surface of the flexible substrate in a lid shape;
An actuator for driving the clamping member so that the film-forming surface of the flexible substrate is sandwiched;
A fixed body in which a hole communicating with the film forming vacuum chamber is formed through the strain center of the wall body caused by a pressure difference between the film forming vacuum chamber and the outside;
A guide body constituting two pairs of opposing reference planes perpendicular to the plane of the fixed body at a position substantially point-symmetric with respect to the strain center of the wall body;
A support for gripping the clamping member while maintaining parallelism between the opposing surfaces of the clamping member;
A rail that is fitted to the reference surface of the guide body and guides the support body so that the film-forming surface of the flexible substrate is sandwiched between the sandwiching members;
A thin film manufacturing apparatus comprising: an extendable / contractible body that moves the support body in a guide direction by the rail. Transporting a flexible substrate to a vacuum chamber for film formation separated from the outside by a wall;
The film forming surface of the flexible substrate is sandwiched in a lid shape while supporting at a position that is substantially point-symmetric with respect to the strain center of the wall due to the pressure difference between the film forming vacuum chamber and the outside. Forming a film forming chamber in the film forming vacuum chamber by driving the sandwiching member to be
A method of forming a film on the film formation surface of the flexible substrate by generating plasma in the film formation chamber while introducing a reactive gas into the film formation chamber. .

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