JPH0967677A - Roll-to-roll film forming device and film formation using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shorten maintenance time and to improve the working rate of a roll-to-roll film forming device by adopting a constitution to take out the film forming chamber in a vacuum chamber outside of the vacuum chamber. SOLUTION: The atm. pressure is restored in the vacuum chamber 101, a flange 102 is removed, an upper cap 112 is opened and the clamp 111 of a microwave waveguide 110 is removed when a film forming stage ends. The flange 102 is then drawn out together with the parts consisting of the film forming chamber 104, etc., by utilizing rails 107, guide mechanism 108, etc., by means of a bracket 106. The film forming chamber 104 is taken out of the vacuum chamber 101 to outside. The film forming chamber is then removed from a plate 105 and the fresh film forming chamber is fixed in place of the removed film forming chamber 104 onto the plate 105 and is inserted into the vacuum chamber 101. The film formation is then executed. As a result, the maintenance characteristics of the device is improved and the working rate is greatly improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a roll-to-roll film forming apparatus for producing a functionally deposited film for a photovoltaic element, various sensors, etc. More specifically, the present invention relates to improvement of an apparatus and its method for shortening the maintenance time of roll-to-roll film formation and improving the operation rate of the apparatus.

[0002]

2. Description of the Related Art In recent years, a power generation system using a solar cell that uses sunlight does not cause problems such as radioactive contamination and global warming, and sunlight is pouring everywhere on the earth. It is a clean system that can deal with future increase in power demand without causing environmental damage, such as less uneven distribution of energy sources, and relatively high power generation efficiency without the need for complicated and large equipment. Has attracted attention as a new power generation method, and various researches and developments have been made toward its practical application. By the way, for a power generation method using a solar cell, in order to establish it as one that covers power demand, the solar cell used is one with sufficiently high photoelectric conversion efficiency and excellent characteristic stability, and It is basically required that it can be mass-produced. For this reason, an easily available gaseous source gas such as silane is used, and this is subjected to glow discharge decomposition, and amorphous silicon (hereinafter referred to as “a-Si”) is formed on a relatively inexpensive substrate such as glass or a metal sheet. A solar cell that can be manufactured by depositing a semiconductor film such as) has high mass productivity and may be manufactured at a lower cost than a solar cell that is manufactured using single crystal silicon or the like. Attracted attention,
Various proposals have been made regarding the basic layer structure, manufacturing method, and the like.

Among these various types of proposed manufacturing methods, a plasma process using microwaves has recently received attention. Since the microwave has a short frequency band, the energy density can be increased as compared with the case where the conventional RF is used, and it is suitable for efficiently generating and sustaining plasma. For example, US Pat.
17,223 and 4,504,518 disclose a method of depositing a thin film on a substrate of small area in a microwave glow discharge plasma under low pressure. In the case of the method, since it is possible to form a film by a process under a low pressure, it is possible to prevent the polymerization of active species that causes deterioration of film characteristics, and not only to obtain a high-quality deposited film, but also to use a plasma. It is said that the generation of powder such as polysilane can be suppressed and the film forming speed can be dramatically improved.

[0004]

However, although microwave plasma can be expected to dramatically improve the film formation rate, in order to introduce microwaves into the film formation chamber, a microwave power source, an isolator, a waveguide, and an Alcera window are required. Microwave applicator means utilizing
The cost required is higher than that of the conventional RF method.
Therefore, for example, in the production of an a-Si solar cell, microwaves are used for producing a photovoltaic layer (i-type a-Si layer) which is thick and requires high throughput, and other layers, that is, n-type a- The RF method is used for forming the Si layer and the p-type a-Si layer. A so-called hybrid system has been proposed.

On the other hand, as another approach to mass production, US Pat. No. 4,400,409 discloses a continuous plasma CVD apparatus adopting a roll-to-roll system. . According to this apparatus, a plurality of glow discharge regions are provided, and a sufficiently long flexible substrate having a desired width is arranged along a path through which the substrates sequentially pass through the glow discharge regions. It is said that an element having a semiconductor junction can be continuously formed by continuously transporting the substrate in the longitudinal direction while depositing and forming a conductive type semiconductor layer required in the discharge region. In this specification, a gas gate is used to prevent the dopant gas used when forming each semiconductor layer from diffusing and mixing into other glow discharge regions. Specifically, a means for separating the glow discharge regions from each other by a slit-shaped separation passage and forming a flow of a scavenging gas such as Ar or H2 in the separation passage is employed. From this, it can be said that the roll-to-roll method is suitable for mass production of semiconductor devices.

In view of the above situation, a rational combination of the microwave and RF hybrid method, which is said to be suitable for mass production, and the roll-to-roll production method results in a mass production method with a higher throughput. But,
The problems described below have become clear even in such an ideal mass production method. The active species, which is a precursor for forming a deposited film, becomes a powder or a film and is deposited at various parts of the film forming chamber other than the target substrate. A film deposited on a portion other than such a substrate begins to peel off from the underlayer when the thickness exceeds a certain limit. Some of the peeled film pieces adhere to the substrate and cause defects in the deposited film. In order to prevent such a situation, it is usually necessary to clean the film formation chamber at a certain number of film formations and at intervals such as total film formation time. However, cleaning the powder or film actually takes a considerable amount of time. For example, when using a file, a brush, etc. to remove the film, it takes time and labor, and it is difficult to clean a small portion that is difficult to reach. Moreover, in the case of powder, there is a risk of ignition. Therefore, usually, a method is adopted in which only the easily removable portion in the film forming chamber is removed, and the film is reused by etching or blasting. Even with this method, it takes a long time to remove and assemble the individual parts, assemble, etch, etc., thus lowering the operation rate of the apparatus. A further problem when using the roll-to-roll method is handling of the belt-shaped substrate during maintenance. This is due to the following circumstances. When the film formation for one bobbin roll of the strip-shaped substrate is completed, the strip-shaped substrate is not usually completely removed from the apparatus. Normally, it is difficult to pass a new strip-shaped substrate through the entire deposition chamber and all gas gates due to the narrow gas gate gap (usually 1 mm to 10 mm), so the rear end of the strip-shaped substrate for the previously deposited film A method is often used in which the tip of the new strip-shaped substrate is adhered to the portion by means such as adhesion or welding, and the tip of the new strip-shaped substrate is pulled by the rear end of the strip-shaped substrate for the previous time and passed through the apparatus. That is, since the strip-shaped substrate does not disappear from the chamber and is always in contact with the film forming chamber, maintenance of the film forming chamber can be prevented.
Alternatively, the fact that the desired component cannot be taken out due to the existence of the belt-shaped substrate occurs. FIG. 7 shows a schematic diagram showing such a situation. In FIG. 7, 701 is a vacuum chamber, 702 is a gas gate, 703 is a belt-shaped substrate, and 704.
Is a top lid, and 705 is a film forming chamber. As is clear from the figure, the components constituting the film forming chamber are the strip-shaped substrate 703.
Is an obstacle and cannot be taken out easily. In addition, the belt-shaped substrate 70
It is difficult to clean the lower part of 3. That is, in the case of a batch type film forming apparatus, maintenance work should be performed after the substrate is taken out, but in the roll-to-roll system, the substrate is left continuously long, which makes main maintenance difficult.

Therefore, the present invention solves the above-mentioned problems in the conventional roll-to-roll film formation, and does not require time to clean the powder and film deposited on a place other than the substrate, and maintainability is improved. It is also an object of the present invention to provide a roll-to-roll film forming apparatus and a method thereof in which the operating rate is improved.

[0008]

In order to achieve the above-mentioned object, the present invention comprises a film-forming chamber that can be pulled out of the vacuum chamber and can be removed from the vacuum chamber. It is an improvement of the operating rate of. That is, it is composed of a plurality of vacuum chambers that have a film formation chamber inside and are connected through gas gates, and the strip-shaped substrate is one of the side walls of the film formation chamber. In a roll-to-roll film forming apparatus for continuously forming a film on the belt-shaped substrate while moving in the longitudinal direction, the film forming chamber is drawn out of the vacuum chamber and detachable from the vacuum chamber. It is characterized by being. In the present invention, the film forming chamber is pulled out of the vacuum chamber by removing a flange that forms one surface of the vacuum chamber and is detachable from the vacuum chamber from the vacuum chamber. At that time, the flange detachably supports the film forming chamber by a supporting mechanism provided in the flange and extending in the direction of the vacuum chamber, and the film forming chamber is guided by the guide mechanism. Can be drawn out of the vacuum chamber. The film forming chamber is connected to a gas supplying unit for supplying a film forming gas to the film forming chamber by a joint having an O-ring, and the gas supplying unit is in the vacuum chamber and is connected to the vacuum chamber. It is provided at a position outside the film forming chamber in a state where the film forming chamber is installed in the chamber. Further, an applicator for introducing electric power into the film-forming chamber, the electric-power-introducing waveguide provided on the film-forming chamber side to the waveguide provided on the flange side of the vacuum chamber. The present invention can be configured to be connected via a connecting clamp, and the present invention can be configured to pull out the film forming chamber to the outside of the vacuum chamber with one touch due to these configurations. When the apparatus of the present invention is used, after the film forming process is completed once or several times, the film forming chamber that has been pulled out of the vacuum chamber and removed from the vacuum chamber has been cleaned. It becomes possible to replace the film forming chamber to form a film. Further, the present invention is effective not only in the case of introducing a microwave into the film forming chamber to form a film, but also in the case of forming a film by introducing RF power.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The contents of the present invention will be described in detail below based on the embodiments of the present invention. According to the present invention, after the film forming process is performed once or several times as described above, the film forming chamber can be pulled out from the vacuum chamber and removed from the vacuum chamber. It does not take time to clean the chamber only by exchanging it, and it is possible to dramatically improve the maintainability and the operation rate of the apparatus. Hereinafter, the content of the present invention will be specifically described with reference to the drawings. 1 to 3 are schematic views showing typical examples of a film forming chamber and a vacuum chamber using microwaves which constitute the roll-to-roll film forming apparatus of the present invention. FIG. 1 is a side view of the same, and is a schematic view showing a state in which the film forming chamber is pulled out together with the flange of the vacuum chamber during maintenance. FIG. 2 is a side view showing a state in which the film forming chamber is installed in the vacuum chamber, and the arrangement is the same as in the actual film forming. FIG. 3 is a top view of the same and shows a state during maintenance as in FIG. Hereinafter, description will be given with reference to these drawings. In FIG. 1, 101 is a vacuum chamber for reducing the pressure inside, and 102 is a detachable flange that forms one surface of the vacuum chamber. In this figure, the flange is removed and pulled out. There is. 10
Reference numeral 3 denotes a bracket fixed to a flange and extending toward the inside of the vacuum chamber, on which the film forming chamber 104 can be detachably installed, and has a gas introduction mechanism inside (not shown in FIG. 2). The plate 105 is supported. The plate 105 is also supported by a bracket 106. The bracket 106 has a roller inside and is movable on the rail 107. On the other hand, the atmosphere side of the vacuum flange 102 is connected to the transfer guide mechanism 108, and has a structure in which the film forming chamber can be smoothly pulled out from the vacuum chamber by hand. Reference numerals 109a and 109b respectively denote microwave applicator means for introducing microwaves into the vacuum chamber, and the atmosphere side is connected to a microwave waveguide (not shown), and microwave power is supplied from a microwave power source (not shown). To be done. Reference numerals 110a and 110b are microwave waveguides for connecting the vacuum chamber and the film forming chamber, respectively, and for introducing microwaves into the film forming chamber from the applicator. The waveguides 110a and 110b and the applicators 109a and 109b are clamps 111a and 1109, respectively.
It is connected and fixed by 11b. Reference numeral 112 denotes an upper lid forming the vacuum chamber 101, which can be opened and closed with the hinge 113 as a fulcrum. An infrared lamp heater 114 for heating the substrate is installed on the upper lid to heat the base 115. In addition, the film forming chamber 104 includes the waveguides 110a and 1a.
It is designed such that the shaded portion in the figure is integrated with 10b so as to be easily removable. The side wall of the film forming chamber serves as an exhaust passage for the film forming gas introduced into the film forming chamber, and is formed by a perforated plate (punching metal) 116 for confining the microwave in the film forming chamber. Waveguide 1
10a and 110b are preferably so-called PF (Pla).
It is desirable to be made in a format called sma-free window. The PF window is constructed by stacking a number of metal fins with a thickness of about 1 mm at intervals of several mm, and by matching with the vibration direction of the microwave, the microwave propagates in the void without loss. But
The plasma decays in the air gap. This prevents abnormal heating of the applicator due to plasma. Incidentally, the state of the fins of the PF window is briefly shown at 110a in FIG.

Next, FIG. 2 will be described. In FIG. 2, 201 is a vacuum chamber for creating a vacuum inside,
Reference numeral 231 denotes an upper lid of the vacuum chamber, which is closed in this figure to reduce the pressure inside. 241 is a removable flange forming a vacuum chamber,
In this figure, the flange is fixed so as to be in close contact with the vacuum chamber 201 via an O-ring in order to reduce the pressure inside. There is a valve 20 on the bottom of the vacuum chamber.
2 and a vacuum pump such as a diffusion pump (not shown) are connected to each other to reduce the pressure in the vacuum chamber. Reference numeral 204 denotes a series of guide mechanisms for pulling out the film forming chambers 236, 237 as described in the description of FIG. 1, and has a plate 205 on which the film forming chambers 236, 237 are placed on the guide mechanism 204. Further, the plate 205 has a gas introduction pipe 206 for film formation.
Is connected. The other end of the gas introduction pipe 206 is a joint 208 having an O-ring 207 and is inserted into a connection sleeve 209 fixed to the vacuum chamber side. Further, a film forming gas is introduced into the connection sleeve through a gas introduction flange 210 from a gas supply device (not shown). Since the connection between the joint 208 and the sleeve 209 is sealed by the O-ring 207, the gas introduced from the gas supply device (not shown) to the gas introduction flange 210 reaches the plate 205 without leakage. The plate 205 has a cavity inside, and the gas introduced from the pipe 206 into the cavity inside the plate passes through a hole provided at the other end of the plate through a gas release hole that penetrates the bottom plate of the deposition chamber to form the deposition chamber. Is released to. On the other hand, an infrared lamp heater 233 is installed on the upper lid 231 via a bracket 232. The temperature sensor 23 is provided so as to be in contact with the base body 234 for forming the deposited film.
Power controlled by a signal from 5 is applied to the lamp heater to heat the substrate to the desired temperature.
Next, reference numeral 236 is a wall forming a film forming chamber, which is fixed to the bottom plate 237. The bottom plate 237 is the plate 205
It is placed on top, and if necessary, they are brought into close contact with and fixed by screws, clamps, etc. 242 is a microwave waveguide, and the applicator 244 is provided by the clamp 243.
It is fixed to.

Next, FIG. 3 will be described. FIG. 3 is a top view of the state in which the film forming chamber is drawn out for the purpose of maintenance. In FIG. 3, 301 is a vacuum chamber. A plate 302 is slid by a guide mechanism 303 and pulled out to the front, and a film forming chamber 304 is placed on the plate. Both sides of the film forming chamber 304 are punching plates as already described, and the film forming gas released from the gas release holes 306 passes through the punching metal and exits the film forming chamber.
Then, it is exhausted to the outside of the system by a vacuum pipe (not shown) connected to the gas outlet 307. 308 is an exhaust port for rough evacuation, and is used only when starting evacuation from a state close to atmospheric pressure.

Next, the film forming process and the maintenance process which are actually performed by using the roll-to-roll film forming apparatus of the present invention described above will be described. The description will be given mainly using FIG. After one film forming process is completed, the inside of the system is sufficiently purged and cooled, and then the exhaust valve is closed to introduce an inert gas such as N2 or Ar into the system to bring the inside of the vacuum chamber to atmospheric pressure. After the pressure in the chamber becomes atmospheric pressure, the flange 102
The jigs such as bolts that fix the unit to the vacuum chamber 101 are removed. Subsequently, the upper lid 112 is opened, and the clamp 111 that fixes the microwave waveguide 110 to the applicator 109 is removed. Then, the flange 102 is mounted on the rail 10 together with the components including the film forming chamber 104.
7, the guide mechanism 108 or the like is used to draw it out so that the film forming chamber comes out of the vacuum chamber. Next, a fixing jig such as a screw that fixes the film forming chamber 104 to the plate 105 is removed. In this state, the film forming chamber 104 can be easily removed together with the microwave guide in a cassette form. Instead of the removed film forming chamber, a newly cleaned film forming chamber is fixed on the plate 105 again. The removed film forming chamber may be cleaned and regenerated before the newly installed film forming chamber is removed again. Preferably,
By preparing several film forming chambers, they can be used while rotating. When a new film forming chamber is installed, the film forming chamber is moved into the vacuum chamber. After that, the flange 102 is fixed to the vacuum chamber 101 with screws or the like, and vacuum sealed. Subsequently, the waveguide 110 and the applicator 109 are connected by the clamp 111, the lid 112 is closed, and vacuum sealing is performed. After the vacuum chamber is vacuum-sealed at all points, the valve connected to the roughing exhaust port shown at 308 in FIG. 3 is opened to reduce the pressure in the system. When the inside of the vacuum chamber is sufficiently decompressed, rough evacuation is stopped, and then the exhaust port 307 is opened. Subsequently, an inert gas such as He or Ar is supplied to the gas introduction flange in FIG. 2 by a gas supply means (not shown). The supplied gas passes through the pipe 206, the plate 205, etc. in FIG. 2 and exits into the film formation space, then passes through the punching board and is exhausted toward the exhaust port. In this state, electric power is supplied to the lamp heater from an electric power supply means (not shown) to start heating the substrate. Heating and baking are usually performed in this state for at least 30 minutes and, if necessary, for several hours or longer until the temperature reaches a sufficient equilibrium and the residual gas in the chamber is sufficiently discharged practically. After heating is completed, film formation is subsequently performed. In order to form a film, first, the supply of gas such as He and Ar used for heating is stopped. Next, at least a film forming raw material gas such as SiH4 and GeH4, and H2 and H added as needed.
Dilution gas such as e, Ar, PH3, BF3, B2
A doping gas such as H6 is adjusted to a desired flow rate and supplied by a gas supply device (not shown). Since such a film forming gas exits from the gas release hole into the film forming chamber and is exhausted through the punching metal, the pressure is determined depending on the relationship between the flow rate and the exhaust speed, etc., but preferably 1 to 100.
It should be adjusted to about mtorr. In this state, when microwave power is applied to the film forming chamber through the applicator 109 and the waveguide 110 shown in FIG. 1 by a microwave power source (not shown), microwave discharge plasma is generated in the film forming chamber to generate a desired deposited film. The formation begins. When the deposited film having a desired film thickness is obtained, the supply of microwave power is stopped and the film formation is stopped. Subsequently, the power supply to the lamp heater is stopped and the system is cooled. After that, return to the beginning of the process and repeat.

Although the steps have been described above, in the present invention, one end of the pipe 206 for supplying the film forming gas from the vacuum chamber to the film forming chamber is a joint 208 having an O-ring 207, and a sleeve 209 is provided. Since it is inserted, it is not necessary to disassemble or assemble the pipe when pulling the film forming chamber out of the vacuum chamber or, conversely, returning it into the vacuum chamber. It is automatically removed or installed when the film forming chamber is pulled out or pushed in.
Therefore, workability can be significantly improved. The same applies to the waveguide 244. Conventionally, an ordinary waveguide is used to fix the applicator and the film forming chamber with a large number of bolts and nuts, so that it is extremely time-consuming and poor in maintainability. In the present invention, the clamp can be removed with one touch. Further, in the case of the conventional microwave film forming apparatus, it was necessary to take out individual parts that were fixed in the vacuum chamber, clean and regenerate them, and then reassemble them. On the other hand, in the present invention, as described above, the double-layered structure in which the detachable film forming chamber is provided in the vacuum chamber, and the place for connecting the vacuum chamber and the film forming chamber is removed with one touch, so that the assembly can be performed. The maintenance has ended very quickly.

Next, the film forming apparatus of the present invention, which uses the RF method, will be described. FIG. 4 is a schematic view showing a typical example of a film forming chamber and a vacuum chamber using RF which constitute the roll-to-roll film forming apparatus of the present invention. In FIG. 4, 401 is a vacuum chamber, 4
Reference numeral 02 denotes a flange forming one surface of the vacuum chamber, a stay 403 is provided inside, and a film forming chamber 404 is detachably placed on the stay 403. The film-forming gas introduction pipe is composed of a joint 405 that connects the pipe on the vacuum chamber side and the pipe on the film forming chamber side through an O-ring as in the case of the microwave method. The deposition gas is introduced through this joint,
Blow out into the film formation chamber from the gas release hole. The flange 402 has a guide mechanism (not shown here) similar to that of the microwave system described above, and can be smoothly attached and detached. The actual film forming process is basically the same as that of the microwave method described above, except for the following items, and therefore is omitted. The difference from the case of the microwave method is that the plasma excitation means is RF (generally, a high frequency such as 13.56 MHz band is widely used), and therefore it is not an applicator means, but an electrode discharge, and a discharge between the cathode and the substrate. Is excited, and the pressure during film formation is 0.1 to 10 torr.
Since it is around r, exhaust means such as a mechanical booster pump is usually used. According to the present invention, even in the film forming apparatus using the RF method, the film forming chamber needs only to be replaced for maintenance as in the case of the microwave method described above, and the apparatus operating rate is dramatically increased. It is improved and the effect of the present invention is great.

[0015]

EXAMPLES The present invention will now be described in detail with reference to examples, but the present invention is not limited to the examples. [Example 1] Using the roll-to-roll film forming apparatus of the present invention, an a-SiGi single layer (single) cell solar cell using an a-SiGe layer as an i-layer (photoelectric conversion layer) was prepared. An example will be given. The roll-to-roll film forming apparatus continuously feeds out a belt-shaped substrate for forming an a-SiGe film from a bobbin wound in a roll shape to form at least an n-type a-Si layer and an i-type a-layer forming a solar cell. SiGe layer, p
A plurality of layers including a type a-Si layer and the like are formed in separate film forming chambers which are reaction vessels, and a plurality of substrates are formed while maintaining a reduced pressure in each film forming space. Of the n-type a-Si layer and the p-type a-Si which are supplied to the respective film forming chambers.
It is provided with a connecting member (generally referred to as “gas gate” or simply “gate”) having a function of preventing mutual diffusion and mixing of gases serving as raw materials of layers and the like. FIG. 5 is a schematic view showing a roll-to-roll film forming apparatus for an a-SiGe solar cell according to the present invention, which is an i-type a-S which requires a high deposited film thickness and high throughput.
The iGe layer is formed by the μω method, and the deposited film thickness is small.
The n-type and p-type a-Si layers that do not require the high sleep of the type a-SiGe layers are formed by the RF method.

In FIG. 5, reference numeral 501 denotes a strip-shaped substrate on which an a-Si film is deposited, which is made of stainless steel in this embodiment. The belt-shaped substrate 501 is wound around a circular bobbin 511 and installed in the delivery chamber 510. The strip-shaped substrate 501 delivered from the bobbin installed in the delivery chamber 510 includes a gas gate (hereinafter simply referred to as “gate”) 520, a vacuum chamber 530 having an n-type a-Si film forming chamber therein, and a gate. 540, a vacuum chamber 550 having an i-type a-SiGe film forming chamber therein, and a gate 56.
0, a vacuum chamber 570 having a P-type a-Si film forming chamber therein, a gate 580, and a winding bobbin 591 installed in a winding chamber 590. 53
0a and 570a are RF power sources, and 530b and 57
Reference numeral 0b is a cathode electrode for exciting RF discharge, and is supplied with electric power for depositing an n-type a-Si layer and a p-type a-Si layer, respectively. Reference numeral 550a is an applicator composed of a dielectric window for radiating microwaves to the discharge space, to which electric power is applied from a microwave power source (not shown) through a rectangular waveguide 550b installed in the dielectric window in a vertical direction, Glow discharge is generated in the discharge space inside the i-type a-SiGe film forming chamber. 502a to 506a are each filled with a gas serving as a raw material for forming a deposited film, and 502a includes SiH4 gas and 5
03a is GeH4 gas, 504a is H2 gas, 505a
Is filled with PH3 gas, and 506a is filled with B2H6 gas. Each gas passes through the on-off valves 502b to 506b and the pressure reducers 502c to 506c, and the gas mixer 530c,
It is led to 550c and 570c. Gas mixer 530c ~
The raw material gas having a desired flow rate and mixing ratio in 570c is jetted into each film forming chamber through gas introduction lines 530d, 550d and 570d. The gas introduced into the film forming chamber is an exhaust device 510e including an oil diffusion pump, a mechanical booster pump, a rotary pump, and the like.
By 30e, 550e, 570e, and 590e, the pressure in each chamber is adjusted so as to be a desired pressure, the gas is exhausted, and the gas is guided to an exhaust gas treatment device (not shown). Also, 530
Reference numerals f, 550f, and 570f denote infrared lamp heaters for heating the substrates, and power supplies 530g, 550g, and 570, respectively.
Power is supplied from g. Reference numerals 541 and 561 are parts for adjusting the opening cross-sectional area of the gate, which narrows the gas flow path,
Mutual diffusion of gases between the film forming chambers is a phenomenon.
Further, a gas that does not adversely affect the film formation, for example, a gas such as H 2 or He is supplied from the cylinder 507 a to the pressure reducer 507 b and the flow rate controller 50 through the gas inlets 542 and 562 in the gate.
7c and 507d to further suppress the mutual diffusion of the source gases in each film forming chamber. The strip-shaped substrate 501 delivered from the delivery chamber 510 advances in each film forming chamber one after another, and has an n-type a-Si film and an i-type a-SiGe film on its surface.
A p-type a-Si film is formed and finally a winding chamber 590
to go into. First, in the vacuum chamber 530 having the n-type a-Si film forming chamber therein, the belt-shaped substrate 501 is heated by the infrared lamp heater 530f to a desired temperature.
Further, the gases such as SiH4, H2, and PH3, which are raw materials of the n-type a-Si film, are mixed by the gas mixer 530c at optimum flow rates and introduced into the film forming chamber. At the same time, RF power is applied to the cathode 530b from the RF power source 530a to cause glow discharge in the film formation space, and an n-type a-Si film is formed on the surface of the belt-shaped substrate 501. Next, the strip-shaped substrate 50
1 passes through the gate 540 and enters the vacuum chamber 550 having the i-type a-SiGe film forming chamber therein. Within 550, SiH4, Ge set to the optimum flow rate as described above.
Optimum power is given to H4 and H2 gas, and the n-type a-Si
A desired i-type a-SiGe film is formed on the film. Similarly, the strip | belt-shaped base | substrate 501 is similarly wound around the bobbin 591 in the winding chamber 590 through the gate 560 and the vacuum chamber 570 which has a p-type a-Si film forming chamber inside. Here, the vacuum chambers 530, 550 and 570 are provided with removable flanges 531 and 5 which are the features of the present invention.
51 and 571 are provided. As described above, the flange is provided with a stay guide mechanism or the like for supporting the detachable film forming chamber. The detailed procedure of the film forming step is omitted because it is as described above. The film forming operation was stopped before the film deposited on the target strip-shaped substrate began to come off, the system was purged, and the exhaust valve was closed to bring the system to atmospheric pressure with N2. After that, the flanges 531, 551 and 571 were pulled out, and each film forming chamber was replaced with a new cleaned spare part. Subsequently, the inside of the system was evacuated again and the film formation was started again. The maintenance time required at this time is compared with the conventional one. In the present invention, a total of 3 hours and 50 minutes of leak 20 minutes, component removal 30 minutes, component regeneration (blasting, etching, etc.) 1 hour, component drying 1 hour, component attachment 40 minutes, and vacuum evacuation 20 minutes were used in the present invention. It took only 1 hour for 20 minutes for leak, 20 minutes for parts replacement and 20 minutes for vacuum evacuation, and we were able to dramatically improve the equipment operation rate.

[Embodiment 2] An example of an apparatus for producing a triple cell solar cell using the roll-to-roll film forming apparatus of the present invention will be described. The solar cell is composed of a-SiGe produced by the microwave method for the bottom cell, a-SiGe produced by the microwave method for the middle cell, and an a-Si photoelectric conversion layer produced by the RF method for the top cell. All the other layers are used by the RF method. FIG. 6 shows a schematic view of a typical example of the film forming apparatus of the present invention for producing such a solar cell. In FIG. 6, 601 is a belt-shaped substrate. The belt-shaped substrate has a width of 350 mm and a thickness of 0.15
It is made of SUS430 of mm and has already undergone cleaning and base treatment in the previous process. The undercoat treatment specifically includes a metal coating or the like for improving the light utilization efficiency by increasing reflection, but details are shown in Table 1. Such a strip-shaped substrate is used for the delivery bobbin 60 installed in the delivery chamber 602.
It is fed from 3 to each film forming chamber. The substrate, which has passed through all the film forming chambers and has been subjected to film formation, is wound up by a winding bobbin 605 installed in the winding chamber 604. Reference numerals 611 to 623 denote vacuum chambers each having a film forming chamber therein, and all chambers are connected together with a delivery chamber 602 and a winding chamber 604 by a gas gate through which a strip-shaped substrate can pass. Further, as the number of chambers increases and the overall length of the apparatus increases, the sagging of the belt-shaped substrate due to gravity cannot be ignored, and therefore all the chambers are preliminarily arranged in a catenary configuration. Although not shown this time, the flange of each vacuum chamber has a structure in which the flange can be removed together with the film forming chamber, which is a feature of the present invention.

The function of the film forming chamber installed in each chamber will be described below. 611; RF deposition chamber for bottom cell n layer deposition 612; RF deposition chamber for bottom cell n / i diffusion prevention layer deposition 613; Microwave deposition chamber for bottom cell i layer deposition 614; Bottom cell i / p diffusion prevention layer RF deposition chamber for deposition 615; bottom cell RF deposition chamber for p layer deposition 616; middle cell n layer deposition RF deposition chamber 617; middle cell n / i diffusion prevention layer deposition RF deposition chamber 618; middle cell Microwave chamber 619 for forming i layer; RF film forming chamber for forming middle cell i / p diffusion prevention layer 620; RF film forming chamber for forming middle cell p layer 621; RF film forming for top cell n layer Chamber 622; RF film forming chamber for top cell i layer film formation 623; RF film forming chamber for top cell p layer film formation A triple cell solar cell is manufactured by using such a film forming apparatus of the present invention. The specific procedure is already described in Example 1.
And detailed description is omitted here. Table 1 shows the detailed film forming conditions.
The transport speed of the strip-shaped substrate was 500 mm / min.
A strip-shaped substrate for one bobbin is wound on a winding bobbin,
Every time the bobbin needs to be replaced (hereinafter referred to as one film formation cycle), film formation is temporarily stopped and all chambers are purged.
Cooled and leaked for maintenance. I-layer deposition chamber 6 using microwave, which requires a high film thickness and has a high deposition rate
Exchanges of 13 and 618 were performed every one film formation cycle, and exchanges of other film formation chambers were performed every five film formation cycles. In this way, a total of 10 film forming cycles were performed. The obtained 10 film formation cycles were performed for 10 minutes, that is, 10 rolls of the solar cell original fabric were cut into 3 1 cm-sized samples per roll, and transparent electrodes (ITO) and collector electrodes (Al) were vapor-deposited.
The solar cell conversion efficiency was evaluated under AM1 light. The characteristic evaluation results of the 30 samples were within the conversion efficiency of 10.58 to 10.75%. All maintenance can be completed very quickly because the vacuum chamber is only leaked and the film forming chamber is replaced, and the operating rate has dramatically improved compared to the past.

[0019]

[Table 1]

[0020]

As described above, according to the present invention, the film forming chamber can be removed from the vacuum chamber by pulling the film forming chamber out of the vacuum chamber. By simple operation of pulling out and removing, it does not take time to clean the powder or film just by exchanging the film forming chamber, and maintainability is improved.
The operation rate of the device can be dramatically improved, and the cost of the product can be reduced. Further, in the present invention, the film forming chamber is connected to a gas supply unit for supplying the film forming gas by a joint having an O-ring, so that the film forming chamber is drawn out of the vacuum chamber, Alternatively, conversely, when returning to the inside of the vacuum chamber, they can be automatically connected according to the pulling out or pushing in, and the workability can be improved. Further, an applicator for introducing electric power into the film-forming chamber, the electric-power-introducing waveguide provided on the film-forming chamber side to the waveguide provided on the flange side of the vacuum chamber. On the other hand, by configuring the connection through the connection clamp, the film formation chamber can be pulled out of the vacuum chamber with one touch, and the maintainability thereof can be further improved.

[Brief description of drawings]

FIG. 1 is a side view showing a state at the time of maintenance in a film forming chamber and a vacuum chamber using microwaves which constitute a roll-to-roll film forming apparatus of the present invention.

FIG. 2 is a side view showing the same arrangement state as in actual film formation in a film formation chamber and a vacuum chamber using microwaves which constitute the roll-to-roll film formation apparatus of the present invention.

FIG. 3 is a top view showing a state at the time of maintenance in a film forming chamber and a vacuum chamber using microwaves which constitute the roll-to-roll film forming apparatus of the present invention.

FIG. 4 is a schematic view showing a film forming chamber and a vacuum chamber using RF which constitute the roll-to-roll film forming apparatus of the present invention.

FIG. 5 is a schematic view showing a roll-to-roll single cell solar cell film forming apparatus of the present invention.

FIG. 6 is a schematic view showing a roll-to-roll triple cell solar cell film forming apparatus of the present invention.

FIG. 7 is a schematic diagram showing a film forming chamber and a vacuum chamber that constitute a conventional roll-to-roll film forming apparatus.

[Explanation of symbols]

101 Vacuum Chamber 102 Front Flange 103 Bracket 104 Film Forming Chamber 105 Plate 106 Bracket 107 Rail 108 Transfer Guide Mechanism 109a, b Microwave Applicator 110a, b Microwave Waveguide 111a, b Connection Clamp 112 Upper Lid 113 Hinge 114 Infrared Lamp Heater 115 Substrate 116 Punching metal 201 Vacuum chamber 202 Gate valve 204 Guide mechanism 205 Plate 206 Gas introduction pipe 207 O-ring 208 Joint 209 Connection sleeve 210 Gas introduction flange 231 Top lid 232 Bracket 233 Infrared lamp heater 234 Base 235 Temperature sensor 236 Wall plate 237 Bottom plate 241 Front Flange 242 Microwave waveguide 243 Clamp for connection 244 microwave applicator 301 vacuum chamber 302 plate 303 transfer guide mechanism 304 film forming chamber 305 punching metal 306 gas discharge hole 307 gas exhaust port 308 roughing gas exhaust port 401 vacuum chamber 402 front flange 403 stay 404 film forming chamber 405 joint 501 Belt-shaped substrate 511, 591 Bobbin for winding the substrate 510 Delivery chamber for substrate 530 Vacuum chamber having n-type a-Si film forming chamber 550 Vacuum chamber having i-type a-SiGe film forming chamber 570 p-type a- Vacuum chamber having Si film forming chamber 590 Base winding chamber 520, 540, 560, 580 Gate 530a, 570a RF power source 550a Microwave applicator 530b, 570b power Sword electrode 550b Waveguide 502a SiH4 gas cylinder 503a GeH4 gas cylinder 504a H2 gas cylinder 505a PH3 gas cylinder 506a B2H6 gas cylinder 502b to 506b Gas cylinder opening / closing valve 502c to 506c Pressure reducer 530c, 530c, 530c 530c 530d, 550d, 570d Gas introduction line 510e, 530e, 550e, 570e, 590e
Exhaust pump 530f, 550f, 570f Heater for heating substrate 530g, 550g, 570g Power supply for heater for heating substrate 507a Purge gas cylinder for gate 507b Pressure reducer 507c, 507d Gas flow rate controller 541, 561 Gap adjustment component 542, 562 Gate gas Inlet port 531,551,571 Detachable front flange 601 Belt-shaped substrate 602 Delivery chamber 603 Delivery bobbin 604 Winding chamber 605 Winding bobbin 611 RF deposition chamber for bottom cell n layer deposition 612 Bottom cell n / i diffusion prevention layer deposition RF deposition chamber 613 Bottom cell i layer microwave deposition chamber 614 Bottom cell i / p diffusion prevention layer deposition RF deposition chamber 615 Bottom cell p layer deposition RF deposition chamber 616 Middle cell n layer deposition RF deposition room 617 Middle cell RF deposition chamber for n / i diffusion prevention layer deposition 618 Microwave deposition chamber for middle cell i layer deposition 619 RF deposition chamber for middle cell i / p diffusion prevention layer deposition 620 RF deposition for middle cell p layer deposition Chamber 621 Middle cell n-layer deposition RF deposition chamber 622 Middle cell i-layer deposition RF deposition chamber 623 Top cell p-layer deposition RF deposition chamber 701 Vacuum chamber 702 Gas gate 703 Belt-shaped substrate 704 Top lid 705 Film deposition chamber

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Hirokazu Ouri 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Hiroshi Echizen 3-30-2 Shimomaruko, Ota-ku, Tokyo Kya Non-Incorporated (72) Inventor Atsushi Hono 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Masahiro Kanai 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc.

Claims (9)

[Claims] 1. A plurality of vacuum chambers having a film forming chamber therein and connected through gas gates at the same time. The plurality of connected chambers are formed so that the strip-shaped substrate is one of the side walls of the film forming chamber. In a roll-to-roll film forming apparatus for continuously forming a film on the strip-shaped substrate while moving in the longitudinal direction of the vacuum chamber, the film forming chamber is pulled out of the vacuum chamber and detached from the vacuum chamber. A roll-to-roll film forming apparatus characterized by being configured to be possible. 2. The film forming chamber is drawn out of the vacuum chamber by removing a flange that forms one surface of the vacuum chamber and is detachable from the vacuum chamber, from the vacuum chamber. The roll-to-roll film forming apparatus according to claim 1. 3. The film is formed by detachably supporting the film forming chamber by a supporting mechanism provided on the flange and extending in the direction of the vacuum chamber, and guiding the supporting mechanism by a guide mechanism. The roll-to-roll film forming apparatus according to claim 2, wherein the chamber is pulled out of the vacuum chamber. 4. The film forming chamber is connected to a gas supply unit for supplying a film forming gas to the film forming chamber via a joint having an O-ring. The roll-to-roll film forming apparatus according to claim 2. 5. The gas supply unit is provided in a position outside the film forming chamber in the vacuum chamber, with the film forming chamber being installed in the vacuum chamber. The roll-to-roll film forming apparatus according to claim 4. 6. In the film forming chamber, a power guiding waveguide provided on the film forming chamber side introduces electric power to the waveguide provided on the flange side of the vacuum chamber. The roll-to-roll film forming apparatus according to any one of claims 1 to 5, wherein the roll-to-roll film forming apparatus is connected to the applicator according to claim 1 through a connecting clamp that can be removed with one touch. . 7. A roll-to-roll film forming method using the apparatus according to claim 1, wherein the vacuum chamber is used after one or several film forming steps. The roll-to-roller is characterized in that the film-forming chamber that has been pulled out of the vacuum chamber and removed from the vacuum chamber is replaced with a new film-forming chamber that has been cleaned to form a film.
Roll film forming method. 8. A roll-to-roll film forming method using the apparatus according to claim 1, wherein microwaves are introduced into the film forming chamber for film formation. Roll-to-roll film forming method. 9. A roll-to-roll film forming method using the apparatus according to claim 1, wherein RF film power is introduced into the film forming chamber for film formation. Roll-to-roll film forming method.