JP2962840B2 - Method and apparatus for continuously forming large-area functional deposition film by microwave plasma CVD - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

The present invention relates to a large-area functional deposition film which generates uniform microwave plasma over a large area, and decomposes and excites a source gas by a plasma reaction caused by the microwave plasma. And a method for continuously forming the same.

More specifically, there is provided a method and an apparatus capable of dramatically increasing the utilization efficiency of the raw material gas, and capable of continuously forming a high-speed, highly uniform functional deposition film over a large area. Specifically, mass production of a large-area thin-film semiconductor device such as a photovoltaic element can be realized at low cost.

[0002]

2. Description of the Related Art In recent years, the demand for electric power has rapidly increased worldwide, and the problem of environmental pollution has become more serious as electric power production has been activated to meet such demand. By the way,
In nuclear power generation, which is expected to be an alternative to thermal power generation and has already entered practical use, serious radioactive contamination damages the human body and reduces the natural environment as represented by the Chernobyl nuclear power plant accident. Invasion has occurred, threatening the future spread of nuclear power, and even some countries have actually established laws and regulations prohibiting the construction of new nuclear power plants.

In addition, the use of fossil fuels, such as coal and petroleum, is steadily increasing in order to meet the increasing demand for electric power even with thermal power generation, and the amount of carbon dioxide emitted increases accordingly. It raises the concentration of greenhouse gases such as carbon dioxide in the atmosphere, causing global warming, and the annual average temperature of the earth is steadily rising.
(International Energy Age
ncy) will reduce CO2 emissions by 2 by 2005
It is recommended to reduce it by 0%.

[0004] Under such a background, the artificial increase in developing countries and the accompanying increase in demand for electric power are inevitable, and the power consumption per capita in developed countries will be further promoted in the future due to the promotion of electronics in lifestyles. With the increase in power supply, the issue of power supply has to be considered on a global scale.

[0005] Under such circumstances, the power generation system using solar cells utilizing sunlight does not cause the above-mentioned problems such as radioactive contamination and global warming, and sunlight is ubiquitous on the earth. Energy sources are less unevenly distributed, and relatively high power generation efficiency can be obtained without the need for complicated large-scale facilities. It has attracted attention as a clean power generation system that can cope with it, and various R & Ds have been made for its practical use.

By the way, regarding a power generation system using a solar cell, in order to establish the power generation system to meet the power demand, the solar cell to be used must have a sufficiently high photoelectric conversion efficiency and excellent characteristic stability. It is basically required to be able to be mass-produced.

In general, a solar cell having an output of about 3 kW per household is required to supply necessary power in a general home. The photoelectric conversion efficiency of the solar cell is, for example, about 10%. Then, the area of the solar cell for obtaining the required output is about 30 m ² . And
For example, in order to supply necessary electric power to 100,000 households, a solar cell having an area of 3,000,000 m ² is required.

For this reason, a gaseous raw material gas such as silane, which is easily available, is used and decomposed by glow discharge to form a semiconductor thin film such as amorphous silicon on a relatively inexpensive substrate such as glass or a metal sheet. Solar cells that can be manufactured by depositing are attracting attention because of their high mass productivity and the potential for low-cost production compared to solar cells that are manufactured using single-crystal silicon. Various proposals have been made.

In a power generation system using a solar cell, a type in which unit modules are connected in series or in parallel to obtain a desired current and voltage by unitization is often adopted.
In each module, it is required that disconnection and short circuit do not occur. In addition, it is important that there is no variation in output voltage or output current between the modules. For this reason, it is required that the uniformity of the characteristics of the semiconductor layer itself, which is the largest characteristic determining factor, is secured at least at the stage of manufacturing the unit module. From the viewpoint of facilitating module design and simplifying the module assembling process, the provision of a semiconductor deposition film having excellent uniformity of characteristics over a large area enhances mass productivity of solar cells, A significant reduction in production costs will be achieved.

In a solar cell, a semiconductor layer, which is an important component, has a semiconductor junction such as a so-called pn junction or pin junction. These semiconductor junctions are formed by sequentially laminating semiconductor layers of different conductivity types, implanting dopants of different conductivity types into a semiconductor layer of one conductivity type by ion implantation, or diffusing them by thermal diffusion. Achieved.

[0011] This point, the above-mentioned attention
Solar cells using thin film semiconductors such as fass silicon
The phosphine (P
H _Three), Diborane (B _TwoH ₆) And other dopant elements
Is mixed with silane, which is the main source gas,
Glow discharge to decompose the half with the desired conductivity type
A conductor film is obtained, and these semiconductor films are sequentially formed on a desired substrate.
Semiconductor bonding can be easily achieved by forming the next layer.
It is known that you can. And from this, Amor
Regarding the production of fass silicon solar cells,
An independent film formation chamber for forming each semiconductor layer is provided.
A method of forming each semiconductor layer in a chamber has been proposed.
You.

Incidentally, US Pat. No. 4,400,409 discloses a roll-to-roll system.
ll) system is disclosed. 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 substrate sequentially passes through each of the glow discharge regions. It is stated that the element having a semiconductor junction can be continuously formed by continuously transporting the substrate in the longitudinal direction while depositing and forming a semiconductor layer of a conductivity type required in the discharge region.
In this specification, a gas gate is used to prevent a dopant gas used for forming each semiconductor layer from diffusing and mixing into another glow discharge region. Specifically, 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 H _{2 in the} separation passage is employed. . From this, it can be said that this roll-to-roll system is suitable for mass production of semiconductor devices.

However, each of the semiconductor layers is formed by R
When performed by a plasma CVD method using F (radio frequency), there is naturally a limit in improving the film deposition rate while continuously maintaining the characteristics of a film formed continuously. That is, for example, even when a semiconductor layer having a thickness of at most 5000 ° is formed, it is necessary to always generate a predetermined plasma over a large area and to maintain the plasma uniformly. However, doing so requires considerable skill and it is difficult to generalize the various plasma control parameters involved.
In addition, the decomposition efficiency and utilization efficiency of the film-forming source gas used are not high, which is one of the factors for raising the production cost.

Further, Japanese Patent Application Laid-Open No. 61-288074 discloses a deposited film forming apparatus using an improved roll-to-roll system. In this apparatus, a hollow continuous portion is formed in a part of a flexible continuous sheet-like substrate installed in a reaction vessel, and active species generated in an activation space different from that of the reaction vessel in this, and It is characterized in that another source gas is introduced as required and a chemical interaction is caused by thermal energy to form a deposited film on the inner surface of the sheet-like substrate forming the holo-like slack portion. By depositing on the inner surface of the holo-like sag as described above, the apparatus can be made compact. Further, since active species that have been activated in advance are used, the film forming speed can be increased as compared with a conventional deposited film forming apparatus.

However, this apparatus utilizes a deposited film forming reaction due to chemical interaction in the presence of thermal energy, and in order to further improve the film forming rate, the amount of active species introduced and Although it is necessary to increase the supply amount of heat energy, there is a limit to the method of supplying heat energy in a large amount and uniformly, and the method of generating a large amount of highly reactive active species and introducing it to the reaction space without loss. is there.

On the other hand, a plasma process using microwaves has recently attracted attention. Since microwaves have a short frequency band, the energy density can be increased as compared with the case where conventional RF is used, and is suitable for efficiently generating and connecting plasma.

For example, US Pat. Nos. 4,517,223 and 4,504,518 disclose depositing a thin film on a small area substrate in a microwave glow discharge plasma at low pressure. Although a method for forming the film is disclosed, according to the method, a high-quality deposited film can be obtained not only because the process is performed under a low pressure, the polymerization of active species that causes deterioration in film characteristics is prevented. Although it is said that the generation of powder such as polysilane in plasma can be suppressed and the deposition rate can be drastically improved, specific disclosure for forming a uniform deposited film over a large area is made. Not.

On the other hand, US Pat. No. 4,729,341 discloses that a photoconductive semiconductor thin film is deposited on a large-sized cylindrical substrate by a high power process using a pair of radiation type waveguide applicators. Although a low-pressure microwave plasma CVD method and apparatus to be formed are disclosed, the large-area substrate is limited to a cylindrical substrate, that is, a drum as a photoreceptor for electrophotography. No application to the substrate has been made.

Further, the manufacturing process of the deposited film is a batch type, and the amount of the deposited film formed by a single preparation is limited, and a large amount of the deposited film is continuously formed on a large-area substrate. There is no disclosure of how to do this.

By the way, since plasma using microwaves has a short microwave wavelength, energy non-uniformity is apt to occur, and there are various problems to be solved with respect to enlargement of the area.

For example, as an effective means for equalizing the microwave energy, there is a use of a slow wave circuit. The slow wave circuit includes a microwave coupling to the plasma as the microwave applicator increases in the lateral direction. Has a unique problem that a sharp decrease in the temperature occurs. Therefore,
As a means for solving this problem, a method of changing the distance between the object to be processed and the slow-wave circuit and making the energy density near the surface of the base uniform has been attempted. For example, U.S. Pat. Nos. 3,814,983 and 4,521,71.
No. 7 discloses such a method. In the former, it is described that the slow-wave circuit needs to be inclined at a certain angle with respect to the substrate, but the transmission efficiency of microwave energy to plasma is not satisfactory. Further, in the latter, it is disclosed that two slow wave circuits are provided in a plane parallel to the base body in a non-parallel manner. That is, it is desirable that the planes perpendicular to the center of the microwave applicator cross each other in a plane parallel to the substrate to be processed and on a straight line perpendicular to the moving direction of the substrate. In order to avoid interference between the two applicators, each of them is displaced laterally to the direction of movement of the substrate by half the length of the waveguide crossbar.

Also, the uniformity of the plasma (ie, the energy
To maintain the uniformity of
It has been done several times. Those suggestions are, for example, journals
Le of Vacuum Science Technology
(Journal of Vacuum Science
e Technology) B-4 (January 1986-
February) 295-298 and B-4 (198
(January-February 2006) Report on pages 126-130
Seen in According to these reports, microwave plasm
The Micro Disk Source (MPDS)
Wave reactors have been proposed. That is, the plasma is disk-shaped
Or it is shaped like a tablet and its diameter is
It is described as a function of the microwave frequency. And
The reports disclose the following: That is,
The plasma disk source to the microwave frequency
Therefore, it can be changed. Place
But a microphone designed to operate at 2.45 GHz
In a microwave plasma disk source, the plasma
Has a confinement diameter of at most about 10 cm.
At least 118cm in volume^ThreeAbout
It cannot be said that the area is increased. The report also states that 915M
System designed to operate at frequencies as low as
In the system, the frequency is reduced to about 40 cm
Diameter and 2000cm^ThreeGiven the plasma volume of
And The report further reports lower frequencies, e.g.
Over 1m by operating at 400MHz
It is said that the discharge can be expanded up to the diameter. However, in this
A very expensive device is required to achieve
Required.

That is, although the plasma area can be increased by lowering the frequency of the microwave, a high-power microwave power supply in such a frequency range has not been generalized and is difficult to obtain. It is extremely expensive, if at all. Also, it is more difficult to obtain a variable-power high-power microwave power supply.

Similarly, as a means for efficiently generating high-density plasma by using microwaves, a method of arranging an electromagnet around a cavity resonator and satisfying ECR (Electron Cyclotron Resonance) conditions has been disclosed in Japanese Patent Application Laid-Open No. H10-163,873. No. 55-141729 and Japanese Patent Application Laid-Open No. 57-133636, etc., and many reports have been made by academic societies and the like that various types of semiconductor thin films are formed using this high-density plasma. This type of microwave ECR plasma CVD apparatus has been commercially available.

However, in these methods using ECR, since a magnet is used for controlling the plasma, the non-uniformity of the magnetic field distribution is added to the non-uniformity of the plasma caused by the wavelength of the microwave. Therefore, it is technically difficult to form a uniform deposited film on a large-sized substrate. In addition, in the case of increasing the size of the device to increase the area,
Electromagnets to be used naturally have been increased in size, resulting in an increase in weight and space, and various problems that must be solved for practical use, such as measures against heat generation and the necessity of a large-current stabilized DC power supply, remain.

Further, the characteristics of the deposited film are not as high as those of the film formed by the conventional RF plasma CVD method. Deposited film and E
Since the characteristics and the deposition rate are extremely different from those of a deposited film formed in a so-called divergent magnetic field space outside the CR conditions, it cannot be said that this method is particularly suitable for manufacturing a semiconductor device that requires high quality and uniformity. .

In the aforementioned US Pat. Nos. 4,517,223 and 4,729,341, it is necessary to maintain a very low pressure in order to obtain a high density plasma. Is disclosed. That is, a process under a low pressure is indispensable to increase the deposition rate and increase the gas use efficiency. However, neither the slow-wave circuit nor the electron cyclotron resonance disclosed in the aforementioned patents is sufficient to maintain the relationship between high deposition rate, high gas utilization efficiency, high power density and low pressure. Things.

Therefore, it is desired to provide a new microwave plasma process which solves the above-mentioned various problems of the microwave means at an early stage.

Incidentally, the thin-film semiconductor has a large area or a large area such as a thin film transistor (TFT) for driving a pixel of a liquid crystal display, a photoelectric conversion element and a switching element for a contact type image sensor in addition to the above-mentioned use for a solar cell. It is also suitable for use in the production of thin film semiconductor devices that need to be long, and has been partially used as a key component for the image input / output device. It is expected that the provision of a new method for forming a deposited film will allow the method to become more widely used.

[Object of the Invention] The present invention overcomes the problems in the conventional method and apparatus for forming a thin film semiconductor device as described above, and forms a functional deposition film uniformly over a large area at high speed. It is an object to provide a novel method and apparatus.

Another object of the present invention is to provide a method and an apparatus for forming a functional deposition film on a continuously moving belt member, the chemical composition of which changes continuously in the longitudinal direction from the belt member. is there.

A further object of the present invention is to provide a method and an apparatus capable of dramatically increasing the utilization efficiency of a source gas for forming a deposited film and realizing mass production of thin film semiconductor devices at low cost. .

Yet another object of the present invention is to provide a method and apparatus for generating a substantially uniform microwave plasma over a large area and a large volume.

Still another object of the present invention is to provide a novel method for forming a photovoltaic device having a high stability and a high photoelectric conversion efficiency continuously on a relatively wide and long substrate. An apparatus is provided.

Still another object of the present invention is to provide a method and an apparatus for forming a semiconductor layer having a forbidden band width continuously changing in the vertical direction from a continuously moving band-shaped member. It is in.

Still another object of the present invention is to provide a method and an apparatus for forming a semiconductor layer on which a valence electron density changes continuously in the vertical direction from a continuously moving strip member. It is in.

[Structure and Effect of the Invention] The present inventors have conducted intensive studies to solve the above-mentioned problems in the conventional thin film semiconductor device forming apparatus and to achieve the object of the present invention. Through a support / transport roller for forming a curved portion, and a support / transport roller for forming a curved end end, and a gap between the support / transport rollers. Curved, leaving
A microwave applicator means for forming a columnar film-forming chamber having the strip-shaped member as a side wall, and radiating microwave energy to both end faces of the film-forming chamber in a direction parallel to a traveling direction of the microwave. Are arranged in opposition to each other,
Further, a source gas for forming a deposited film is introduced into the film forming chamber, and the gas is exhausted from a gap left between the pair of supporting / transporting rollers to reduce the pressure in the film forming chamber to a predetermined pressure. Holding the microwave applicator means to radiate the microwave energy substantially parallel to the side wall, the knowledge that the microwave plasma can be generated substantially uniformly in the width direction of the strip-shaped member in the film forming chamber. Obtained.

The present invention has been completed as a result of further studies based on the above findings, and a large-area functional deposited film is continuously formed by a microwave plasma CVD method, which is described below. And methods and apparatus for forming the same.

The method of the present invention is as follows. That is, while continuously moving the band-shaped member in the longitudinal direction, a columnar film-forming space having the moving band-shaped member as a side wall is formed in the middle of the band-shaped member, and at least two or more kinds of compositions having different compositions are formed in the film-forming space. Each of the source gases for forming a deposited film is separately introduced via a plurality of gas supply means, and simultaneously, microwave energy is applied from a microwave applicator means for emitting microwave energy in a direction parallel to the traveling direction of the microwave. Irradiating the microwave energy to generate microwave plasma in the film-forming space, and the composition is controlled on the surface of the belt-shaped member which continuously constitutes the side wall which is exposed to the microwave plasma. Plasma CVD characterized by forming a deposited film
This is a method in which a large-area functional deposition film is continuously formed by the method.

In the method of the present invention, the moving belt-shaped member is provided with a curved start end forming unit and a curved end end forming unit by using a curved start end forming unit and a curved end end forming unit. The band-shaped member is curved so as to leave a gap in the longitudinal direction of the band-shaped member therebetween so as to form a side wall of the film forming space.

Then, the band-shaped member is formed as a side wall. The microwave energy is radiated into the film formation space via at least one or more of the microwave applicator means disposed on one or both sides of both end surfaces of the columnar film formation space. .

Further, the microwave applicator means is disposed in a direction perpendicular to the end face so as to radiate the microwave energy in a direction parallel to the side wall.

In the method of the present invention, the microwave energy is radiated through a microwave transparent member provided at a tip portion of the microwave applicator means.

Then, the microwave-permeable member is kept airtight between the microwave applicator means and the film forming space.

In the case where the microwave applicator means is disposed so as to face each other on both end surfaces, microwave energy radiated from one microwave applicator means is received by the other microwave applicator means. Be placed so as not to be.

In the method of the present invention, the microwave energy radiated into the columnar film-forming space is prevented from leaking out of the film-forming space.

In the method of the present invention, each of the gas supply means is disposed in parallel to a width direction of the band-shaped member constituting the side wall, and the gas for forming the deposited film is directed toward the adjacent band-shaped member. Release in the direction.

The raw material gas for forming a deposited film introduced into the film forming space is filled in a gap left in the longitudinal direction of the band-shaped member between the curved start end forming means and the curved end end forming means. Try to exhaust more.

In the method of the present invention, at least one surface of the band-shaped member is subjected to a conductive treatment.

Further, the apparatus of the present invention is an apparatus for continuously forming a functional deposition film on a continuously moving strip member by a microwave plasma CVD method, wherein the strip member is moved in the longitudinal direction thereof. There is a columnar film forming chamber formed with the band-shaped member as a side wall and capable of holding the inside thereof substantially at a vacuum, through a curved portion forming means for bending the intermediate member while moving continuously. A microwave applicator means for emitting microwave energy in a direction parallel to a direction in which the microwave travels to generate microwave plasma in the film forming chamber; and exhausting the film forming chamber. Exhaust means, at least two or more gas supply means for introducing a source gas for forming a deposited film into the film forming chamber, and temperature control for heating and / or cooling the strip-shaped member And a step of forming a composition-controlled deposition film on a surface of the continuously moving strip-shaped member which is exposed to the microwave plasma. This is a continuous film forming apparatus.

[0051] In the apparatus of the present invention, the bending portion forming means includes at least one set of a bending start end forming means and a bending end end forming means, and the bending start end forming means and the bending end end forming means. And means are disposed leaving a gap in the longitudinal direction of the strip-shaped member.

The curved portion forming means comprises at least a pair of support / transport rollers and a support / transport ring, and the pair of support / transport rollers leave a gap in the longitudinal direction of the band-shaped member. Are arranged in parallel.

In the apparatus of the present invention, at least one or more of the microwave applicator means is disposed on one or both sides of both end faces of a columnar film forming chamber formed with the strip-shaped member as a side wall. .

[0054] The microwave applicator means is disposed in a direction perpendicular to the end face.

In the apparatus of the present invention, the microwave applicator means is air-tightly separated from the film forming chamber and the microwave applicator means at the tip of the microwave applicator means, and the microwave energy radiated from the microwave applicator means. Is disposed in the film formation chamber.

In the apparatus of the present invention, at least one surface of the band-shaped member is subjected to a conductive treatment.

In the apparatus of the present invention, microwave energy is transmitted to said microwave applicator means via a square and / or elliptical waveguide.

In the case where the microwave applicator means is disposed so as to face each other at both end surfaces of the film forming chamber, the length of the rectangular and / or elliptical waveguide connected to the microwave applicator means may be reduced. The faces including the sides, the faces including the long axis, or the faces including the long side and the faces including the long axis are arranged so as not to be parallel to each other.

Also, the angle between the plane including the long side and / or the plane including the long axis of the rectangular and / or elliptical waveguide and the plane including the central axis of the pair of supporting and conveying rollers is not perpendicular. It is arranged as follows.

In the apparatus of the present invention, each of the gas supply means is disposed in parallel with a width direction of the belt-like member constituting the side wall.

The gas supply means is provided with a gas discharge hole directed to a belt-like member constituting the adjacent side wall.

Hereinafter, experiments performed by the present inventors to complete the present invention will be described in detail.

[Experiment] Various experiments were conducted on the conditions for generating microwave plasma for uniformly forming a functional deposition film on a belt-shaped member using the apparatus of the present invention.
Details will be described below.

EXPERIMENTAL EXAMPLE 1 In this experimental example, the apparatus shown in Apparatus Example 2 to be described later was used, and microwave plasma was generated according to the procedure described in Production Example 1 to be described later. The stability of microwave plasma and the degree of leakage of microwave to the outside of the deposition chamber were examined by the difference in the mounting angle of the slab.

FIG. 6 is a schematic cross-sectional view for explaining the mounting angles of the rectangular waveguides 111 and 112. As shown in FIG.

The rectangular waveguide 111 shown by a solid line and the rectangular waveguide shown by a dotted line are connected to a microwave applicator (not shown) disposed opposite to both end surfaces of the film forming chamber 116. For example, the rectangular waveguide 111 is disposed on the front side in the drawing, and the rectangular waveguide 112 is disposed on the rear side. O is the center of the curved shape, and AA 'is the supporting / transporting roller 102.
And a plane including the central axis of the axis 103, and a plane perpendicular to this plane is designated as HH '. The angle between the plane BB ′ parallel to the plane including the long side of the rectangular waveguide 111 and HH ′ is θ, and this is the angle at which the rectangular waveguide 111 is attached. The angle between the plane CC ′ parallel to the plane including the long side of the rectangular waveguide 112 and HH ′ is θ _2, and this is the angle at which the rectangular waveguide 112 is attached. Here, the mounting angles θ ₁ and θ ₂ of the rectangular waveguides 111 and 112 are 18
When it exceeds 0 °, HH ′ when it is 180 ° or less
, The arrangement relation is the same as the case of 180 ° or less. Of course, even if θ ₁ and θ ₂ are interchanged, since they are opposed to each other, the arrangement relationship is still the same.

In the present invention, the support / transport roller 1
The distance between the curved ends of the belt-shaped member defined by 02 and 103 is defined as a gap L.

Experiments and evaluations were performed on the microwave plasma stability and the like under the microwave plasma discharge conditions shown in Table _{1 under} various combinations of θ ₁ and θ ₂ shown in Table ₂ .

The degree of microwave leakage was evaluated by providing a microwave detector at a position about 5 cm away from the gap between the supporting / transporting rollers 102 and 103.

The evaluation results are as shown in Table 2.

From these results, it was found that by changing the mounting angle of the rectangular waveguide to the microwave applicator, the stability of the microwave plasma and the degree of leakage of the microwave to the outside of the film forming chamber were greatly changed. . Specifically, when θ ₁ and / or θ ₂ is 0 °, the leakage amount of the microwave is the largest, the discharge state is unstable, and
At about °, although the amount of microwave leakage is small,
The discharge state is unstable. At 30 ° or more, microwave leakage was eliminated and the discharge state was stabilized. However,
When the angle between θ ₁ and θ ₂ is 0 ° or 180 °, that is, when the planes including the long sides of the rectangular waveguide are arranged parallel to each other, regardless of the amount of microwave leakage, oscillation Power supply noise increases and discharge becomes unstable. In addition, in this discharge experiment, when the belt-shaped member 101 was stopped and when it was transported at a transport speed of 1.2 m / min, there was no particular difference in discharge stability between the two. .

Further, among the microwave plasma discharge conditions, the type and flow rate of the raw material gas and the position of the gas introduction pipe to be used, the microwave power, the inner diameter of the curved shape, and the pressure inside the film forming chamber are variously changed. No particular difference was found in the amount of microwave leakage and discharge stability caused by the arrangement of the rectangular waveguides.

EXPERIMENTAL EXAMPLE 2 In this experimental example, the apparatus shown in the apparatus example 2 was used and the supporting / transporting roller 10 shown in FIG.
The stability of the microwave plasma and the effect on the film thickness distribution when the gap L of 2 and 103 was changed were examined.

The gap L was varied in the range shown in Table 3 and discharge was performed for about 10 minutes. Other microwave plasma discharge conditions were the same as those shown in Table ₁ , and the mounting angles θ ₁ and θ ₂ of the rectangular waveguide were both set at 45 °. However, the change in the film forming chamber pressure is caused by the fact that the conductance is increased by increasing the gap L without adjusting the capacity of the exhaust pump. Note that the surface temperature of the belt-shaped member 101 is 250
Operating the temperature control mechanisms 106a to 106e to reach
The conveying speed of the belt-shaped member was 35 cm / min.

Table 3 shows the results of evaluation of the discharge state, film thickness distribution, and the like.

The discharge state was visually observed, and the film thickness distribution was measured by a needle-step-type film thickness meter by 10 points in the width direction of the band-shaped member and by 20 cm in the longitudinal direction.
The distribution was evaluated.

From these results, it was found that the capacity of the exhaust pump was not adjusted, and the pressure in the film forming chamber was changed by changing the gap L, and the film thickness distribution of the deposited film formed therewith was particularly affected by the band-shaped member. It was found that the change was remarkable in the width direction. Further, even when the mounting angle of the rectangular waveguide was set such that microwave leakage did not occur in Experimental Example 1, it was found that microwave leakage would still occur if the gap L was too large. And the gap L
The microwave leakage from the gap is reduced when the dimension of the gap L is set to preferably １ ／ wavelength or less, more preferably １ ／ wavelength or less of the microwave wavelength. Note that the film thickness distribution in the longitudinal direction of the belt-like member was almost good as long as the belt-like member was conveyed. Sample No. which had a high deposition rate and a good film thickness distribution among the prepared samples. The deposition rate of No. 4 was about 100 ° / sec. The source gas utilization efficiency calculated from the amount of the film deposited on the belt-shaped member was 55% with respect to the total flow rate of the source gas used.

In the microwave plasma discharge conditions, when the microwave power, the inner diameter of the curved shape, and the like are variously changed, the film thickness distribution and the discharge stability are slightly changed, but the gap L is large. It could not be a solution to the essential problem arising from this.

Experimental Example 3 In this experimental example, as in Experimental Example 1, the apparatus shown in Apparatus Example 2 was used to change the stability of the microwave plasma when the inner diameter of the formed curved shape was changed, The thickness distribution and the like were examined. The microwave plasma discharge conditions shown in Table 1 were used except that the inner diameter of the curved shape was variously changed in the range shown in Table 4, and the mounting angles θ ₁ , θ ₂ were both arranged at 45 °.
The discharge time was 10 minutes each, and the surface temperature of the belt-shaped member was 250 ° C. as in Experimental Example 2. The conveying speed of the belt-shaped member was 35 cm / min.

Table 4 shows the results of evaluation of the discharge state, film thickness distribution, and the like.

The discharge state was visually observed, and the film thickness distribution was measured by a needle step type film thickness meter at 10 points in the width direction of the belt-shaped member and at 20 cm in the longitudinal direction.
The distribution was evaluated.

From these results, by changing the inner diameter of the curved shape without changing the other discharge conditions, the discharge state changes, and the film thickness distribution of the deposited film to be formed is changed particularly in the width direction of the belt-shaped member. It turned out to change remarkably.
The film thickness distribution in the longitudinal direction of the belt-like member was almost good as long as the belt-like member was conveyed.

Further, even when the microwave power, the pressure in the film forming chamber, and the like among the microwave plasma discharge conditions are variously changed, the film thickness distribution and the discharge stability are affected by the respective parameter changes. I understood.

Experimental Example 4 In this experimental example, as in Experimental Example 1, the apparatus shown in Apparatus Example 2 was used, the pressure in the film forming chamber was kept constant, and the raw material gas flow rate and microwave power were varied. The stability of microwave plasma was studied. The film forming chamber pressure and the source gas flow rate were the same as the microwave plasma discharge conditions shown in Table 1 except that they were variously changed within the range shown in Table 5, and the mounting angle of the rectangular waveguide was set. θ ₁ and θ ₂ were both set at 60 ° and 60 °.

The raw material gas is supplied to the gas introduction tubes 113a, 1
13b and 113c introduced evenly.

Table 5 shows the results of the evaluation of the discharge state. Here, .largecircle. Indicates a stable discharge, .largecircle. Indicates a state where discharge is stable although there is a slight flicker, and .DELTA. Indicates a state where discharge is stable at a usable level although there is slight flicker. In either case, the discharge becomes unstable or occurs when the microwave power is reduced, the pressure in the film formation chamber is reduced, or the flow rate of H ₂ H ₂ as the source gas is increased. It almost represents the limit value that disappears. Therefore, it was found that when the microwave power was increased, the pressure in the film forming chamber was increased, or the flow rate of SiH ₄ as the source gas was increased, the discharge became more stable. In this discharge experiment, the case where the band-shaped member 101 was stationary and the case where 1.
The transport was performed at a transport speed of 2 m / min. However, no particular difference was observed in the discharge stability between the two.

Experimental Example 5 In this experimental example, as in Experimental Example 1, the apparatus shown in Apparatus Example 2 was used to change the microwave plasma stability and film thickness distribution when the width of the belt-shaped member was changed. We examined the effects of the above.

The width of the strip was varied in the range shown in Table 6 and discharge was performed for 10 minutes. Other microwave plasma discharge conditions are the same as those shown in Table 1, and the type of the rectangular waveguide is EIA.
Instead of J and WRI-32, they were arranged so that the mounting angles θ ₁ and θ ₂ were 60 ° and 60 °, respectively. The surface temperature of the belt-shaped member was set to 250 ° C. as in Experimental Example 2, and the transfer speed was set to 50 cm / min.

The sample No. For Nos. 15 to 17, only one side of the microwave applicator was used. 18 ~
21 was provided in a pair facing each other.

Table 6 shows the results of evaluation of the discharge state, film thickness distribution, and the like. The evaluation method was the same as in Experimental Example 2.

From these results, it was found that the stability of the microwave plasma and the film thickness distribution were changed by changing the width of the band-shaped member. Even when the microwave power is supplied only from one side and the stability of the microwave plasma is lacking or the film thickness distribution is increased, it can be improved by providing a pair of microwave applicators facing each other. understood.

In the microwave plasma discharge conditions, when the kind and flow rate of the raw material gas and the position of the gas introduction pipe to be used, microwave power, chamber pressure in the film formation, etc. were variously changed, the respective parameters were changed. It was found that the stability and film thickness distribution of the microwave plasma were affected.

Outline of Experimental Results In the method and apparatus of the present invention, the stability and uniformity of the microwave plasma are determined by, for example, the shape of the microwave applicator, the type and arrangement of the waveguide connected thereto, Since various parameters such as the pressure in the film formation chamber, microwave power, degree of confinement of microwave plasma, volume and shape of discharge space are maintained in a complicated manner, optimal conditions can be determined with only a single parameter. Although it is difficult, the following tendency and condition range were found from the results of this experiment.

Regarding the pressure in the film forming chamber, it is preferable that
5 mTorr to 100 mTorr, more preferably 3 mTorr
It was found to be between mTorr and 50 mTorr. Regarding the microwave power, preferably 250 × 2 W to 3000 × 2 W, more preferably 300 × 2 W to 10 × 10 W
It turned out to be 00 × 2W. It has been found that the inner diameter of the curved shape is preferably between 7 cm and 45 cm, more preferably between 8 cm and 35 cm. In addition, it was found that when a pair of microwave applicators facing each other was used, the width of the belt-shaped member was preferably about 60 cm, more preferably about 50 cm, to obtain uniformity in the width direction.

Further, it is found that when the amount of microwave leakage from the microwave plasma region increases, the stability of the microwave plasma is lost, and the gap L between the curved ends of the band-shaped member is determined.
It has been found that it is preferable to set the wavelength to preferably 波長 wavelength or less, more preferably 以下 wavelength or less.

Hereinafter, the method of the present invention will be described in more detail based on the facts found by the above [Experiment]. In the method of the present invention, most of the side wall of the columnar film-forming space formed by bending the band-shaped member using the bending start end forming unit and the bending end end forming unit in the middle of the moving band-shaped member. Is formed of the moving strip-shaped member, and a gap is left between the bending start end forming means and the bending end end forming means in the longitudinal direction of the strip-shaped member.

In the method of the present invention, in order to uniformly generate and confine microwave plasma in the columnar film forming space, the film is formed in a direction parallel to a side wall formed by the band-shaped member. Microwave energy is radiated from one or both sides of both ends of the space to confine the microwave energy in the film formation space.

When the width of the belt-like member is relatively narrow,
Even when microwave energy is emitted from only one side, the uniformity of the microwave plasma generated in the film formation space is maintained, but the width of the band-shaped member exceeds, for example, one wavelength of the microwave. It is preferable to radiate microwave energy from both sides in order to maintain uniformity of microwave plasma.

Of course, the uniformity of the microwave plasma generated in the film formation space requires that microwave energy be sufficiently transmitted into the film formation space. Preferably, the structure is similar to a tube. For this purpose, first, the belt-like member is preferably made of a conductive material. However, at least one surface thereof may be subjected to a conductive treatment.

Further, in the method of the present invention, both ends of a columnar film-forming space formed by bending the moving belt-shaped member using the bending start end forming means and the bending end end forming means are formed. It is preferable that the microwave energy radiated into the film formation space is transmitted to the film formation space almost uniformly, and a circular shape, an elliptical shape,
It is desirable that the shape be similar to a square shape or a polygonal shape, be substantially symmetrical, and have a relatively smooth curved shape. Of course,
In a gap portion left in the longitudinal direction of the band-shaped member between the bending start end forming means and the bending end end forming means, the end face shape may be discontinuous.

Further, in the method of the present invention, the microwave energy can be efficiently transmitted in the film forming space, and the microwave plasma can be stably generated and maintained.
For control, the microwave transmission mode in the microwave applicator means is preferably a single mode. Specifically, TE ₁₀ mode, TE ₁₁ mode,
An eH ₁ mode, a TM ₁₁ mode, a TM ₀₁ mode, and the like can be given, and preferably, a TE ₁₀ mode, a TE ₁₁ mode, and an eH ₁ mode are used. These transmission modes may be used alone or in combination. Also,
Microwave energy is transmitted to the microwave applicator means via a waveguide capable of transmitting the above-described transmission modes. Further, the microwave energy is radiated into the film forming space via an airtight microwave permeable member provided at a tip portion of the microwave applicator means.

In the method of the present invention, a gap is left in the film forming space between the bending start end forming means and the bending end end forming means, and the raw material gas is exhausted from the gap, and Although the inside of the film space is maintained at a predetermined reduced pressure, the size of the gap is such that a sufficient exhaust conductance is obtained, and at the same time, the microwave energy radiated into the film formation space is out of the film formation space. Special care needs to be taken to prevent leakage.

More specifically, the direction of the electric field of the microwave propagating in the microwave applicator means, the center axis of the support / transport roller as the bending start end forming means, and the support / conveyance as the bending end end forming means. The microwave applicator means is arranged so that the plane including the central axis of the transport roller is not parallel to each other.

When microwave energy is radiated into the film-forming space via a plurality of the microwave applicator means, it is necessary to consider each microwave applicator means as described above.

Further, the maximum dimension of the opening width in the longitudinal direction of the band-like member in the gap left between the bending start end forming means and the bending end end forming means is preferably １ ／ of the wavelength of the microwave. It is desirable that the wavelength be equal to or less than the wavelength, more preferably, equal to or less than １ ／ wavelength.

In the method of the present invention, when a plurality of the microwave applicator means are arranged so as to face each other, the microwave energy radiated from one microwave applicator means is used for the other microwave applicator means. Received, the received microwave energy reaches the microwave power supply connected to the other microwave applicator means, and damages the microwave power supply or causes an abnormality in microwave oscillation. Special care must be taken to avoid adverse effects such as Specifically, the microwave applicator is arranged so that the directions of electric fields of the microwaves traveling in the microwave applicator means are not parallel to each other.

In the method of the present invention, when microwave energy is emitted from only one of the two end faces of the film forming space, it is necessary to prevent the microwave energy from leaking from the other end face. The end face is sealed with a conductive member, or the hole diameter is preferably 以下 wavelength or less, more preferably １ ／ wavelength of the microwave wavelength used.
It is desirable to cover with a wire mesh having a wavelength equal to or less than the wavelength or a punching board.

In the method of the present invention, the microwave energy radiated into the film forming space depends on the type of the source gas introduced into the film forming space, but is strong against the pressure in the film forming space. While having a correlation, it shows a tendency to significantly decrease with an increase in the distance from the microwave transmitting member provided in the microwave applicator. Therefore, when a relatively wide band-shaped member is used, in order to generate uniform microwave plasma in the width direction, the pressure in the film formation space is kept sufficiently low, and both ends of the film formation space are formed. From the surface, it is desirable to radiate microwave energy into the film forming space through at least one pair or more of microwave applicator means.

[0109] In the method of the present invention, the microwave applicator means may form the film so that a traveling direction of the radiated microwave energy is substantially parallel to a side wall of a film forming space formed by the band-shaped member. It is desirable to arrange them perpendicular to the end face of the space. Further, it is desirable that the microwave applicator means is disposed at a position substantially equidistant from the side wall. However, when the curved shape of the side wall is asymmetric, the position where the microwave applicator is disposed is not particularly limited. Absent. Of course, even when a plurality of microwave applicator means are arranged facing each other, their central axes may or may not be on the same line.

In the method of the present invention, the curved shape formed by the band-shaped member may be kept constant in order to maintain the stability and uniformity of the microwave plasma generated therein. Preferably, the band-shaped member is wrinkled by the bending start end forming means and the bending end end forming means.
It is desirable that the support is made so as not to cause slack, lateral displacement and the like. Further, in addition to the bending start end forming means and the bending end end forming means, a support means for holding a curved shape may be provided. Specifically, a support means for continuously holding a desired curved shape may be provided inside or outside the curved band-shaped member. In the case where the support means is provided inside the curved band-shaped member, care should be taken to minimize the portion in contact with the surface on which the deposited film is formed. For example, it is preferable to provide the support means at both ends of the band-shaped member.

As the belt-shaped member, it is desirable to use a flexible member capable of continuously forming the curved shape, and to form a smooth shape at a curved start end, a curved end end, and an intermediate curved portion.

In the method of the present invention, when each of at least two or more kinds of source gas for forming a deposited film having a different composition is separately introduced from a plurality of gas supply means into the film formation space, the gas supply means may be used. Is preferably discharged uniformly in the width direction of the band-shaped member and in one direction toward the band-shaped member close to the gas supply means. That is, the gas discharge ports opened in each of the gas supply means are directed to different directions so that the respective deposition film forming raw material gases having different compositions do not mix with each other immediately after being discharged from the gas supply means. It is desirable.

The gas supply means is arranged in parallel to the strips constituting the side walls.

The number of the gas supply means used in the method of the present invention is desirably at least equal to or greater than the number of component elements of the functional deposition film to be formed. By appropriately changing the composition of the deposited film forming source gas to be released, a functional deposited film whose composition is controlled can be formed.

It is desirable that each of the gas supply means is disposed so as to be contained in the columnar film-forming space so as to surely excite and decompose the discharged material gas for forming a deposited film. In addition, in order to give a desired composition distribution to the deposited film to be formed, it is desirable to appropriately adjust the arrangement of the gas supply means. Further, a rectifying plate may be provided in the columnar film forming space in order to adjust and control the flow path of the source gas for forming a deposited film in the columnar film forming space.

The functionally-deposited film of controlled composition formed by the method of the present invention includes SiGe, SiC, Ge
So-called Group 4 alloy semiconductor thin film such as C, SiSn, GeSn, SnC, GaAs, GaP, GaSb, InP, InAs
So-called 3-5 group compound semiconductor thin films, such as ZnSe, ZnS,
So-called group 2-6 compound semiconductor thin films such as ZnTe, CdS, CdSe, CdTe, CuAlS ₂ , CuAlSe ₂ , Cu
AlTe ₂ , CuInS ₂ , CuInSe ₂ , CuInT
e ₂ , CuGAs ₂ , CuGaSe ₂ , CuGaTe, A
gInSe _2, AgInTe ₂ Hitoshishoi 1-3-6 compound semiconductor thin film, ZnSiP _2, ZnGeAs _2, CdSia
So-called _2-4- V group compound semiconductor thin films such as S ₂ and CdSnP ₂ , Cu ₂ O, TiO ₂ , In ₂ O ₃ , SnO ₂ , ZnO,
Examples include so-called oxide semiconductor thin films such as CdO, Bi ₂ O ₃ , and CdSnO ₄ , and those containing a valence electron controlling element for controlling valence electrons of these semiconductors. Also,
Examples include a so-called Group 4 semiconductor thin film such as Si, Ge, and C containing a valence control element. Of course a-S
In an amorphous semiconductor such as i: H, a-Si: H: F, the content of hydrogen and / or fluorine may be changed.

By controlling the composition of the above-described semiconductor thin film, the forbidden band width control, valence electron control, refractive index control,
Crystal control and the like are performed. By forming a functional deposition film whose composition is controlled in the vertical or horizontal direction on the belt-like member, a large-area thin-film semiconductor device having excellent electrical, optical, and mechanical properties can be manufactured. .

That is, by changing the forbidden band width and / or the valence electron density in the longitudinal direction of the deposited semiconductor layer, the mobility of carriers is increased, and the recombination of carriers at the semiconductor interface is prevented. The electrical characteristics are improved.
In addition, by continuously changing the refractive index to form an optically non-reflective surface, the light transmittance into the semiconductor layer can be improved. Furthermore, stress relaxation is performed by giving a structural change by changing the hydrogen content and the like,
A deposited film with high adhesion to a substrate can be formed.
Further, by forming semiconductor layers having different crystallinity in the lateral direction, for example, a photoelectric conversion element formed of an amorphous semiconductor and a switching element formed of a crystalline semiconductor are simultaneously formed continuously on the same substrate. I can do it.

In the present invention, the material gas for forming a deposited film used for forming the above-mentioned functional deposited film is prepared by appropriately adjusting the mixing ratio thereof according to the structure of the desired functional deposited film. Introduce into the membrane space. Although a plurality of gas supply means are used for the introduction, the composition of the deposited film forming source gas introduced from each gas supply means may be different, or may be the same depending on the purpose. Further, the composition may be changed continuously over time.

In the present invention, the compound containing a Group 4 element of the periodic table, which is preferably used for forming a Group 4 semiconductor or a Group 4 alloy semiconductor thin film, includes Si atom, Ge atom, C atom and Sn atom. , Pb atom, specifically, SiH ₄ , Si ₂ H ₆ , Si ₃ H ₈ , Si ₃ H
₆ , silane compounds such as Si ₄ H ₈ and Si ₅ H ₁₀ , Si
F ₄ , (SiF ₂ ) ₅ , (SiF ₂ ) ₆ , (SiF ₂ ) ₄ , S
i ₂ F ₆ , Si ₃ F ₈ , SiHF ₃ , SiH ₂ F ₂ , Si ₂ H ₂
F ₄ , Si ₂ H ₃ F ₃ , SiCl ₄ , (SiCl ₂ ) ₅ , Si
Br ₄ , (SiBr ₂ ) ₅ , Si ₂ Cl ₆ , Si ₂ Br ₆ , S
halogenated silane compounds such as iHCl ₃ , SiHBr ₃ , SiHI ₃ , Si ₂ Cl ₃ F ₃ , germane compounds such as GeH ₄ , Ge ₂ H ₆ , GeF ₄ , (GeF ₂ ) ₅ , (Ge
F ₂ ) ₆ , (GeF ₂ ) ₄ , Ge ₂ F ₆ , Ge ₃ F ₈ , GeHF
₃ , GeH ₂ F ₂ , Ge ₂ H ₂ F ₄ , Ge ₂ H ₃ F ₃ , GeC
l ₄ , (GeCl ₂ ) ₅ , GeBr ₄ , (GeBr ₂ ) ₅ , G
_{e 2 Cl 6, Ge 2 Br} 6, GeHCl 3, GeHBr 3, G
halogenated germanium compounds such as eHI ₃ and Ge ₂ Cl ₃ F ₃ , methane series hydrocarbon gases such as CH ₄ , C ₂ H ₆ and C ₃ H ₈ , and ethylene series carbonization such as C ₂ H ₄ and C ₃ H ₆ Hydrogen gas, C ₆
Cyclic hydrocarbon gas such as H ₆ , CF ₄ , (CF ₂ ) ₅ , (CF
₂ ) ₆ , (CF ₂ ) ₄ , C ₂ F ₆ , C ₃ F ₈ , CHF ₃ , CH ₂ F
₂ , CCl ₄ , (CCl ₂ ) ₅ , CBr ₄ , (CBr ₂ ) ₅ ,
C ₂ Cl ₆ , C ₂ Br ₆ , CHCl ₃ , CHI ₃ , C ₂ Cl ₃ F
Halogenated carbon compounds such as ₃ , SnH ₄ , Sn (CH ₃ ) ₄
And lead compounds such as Pb (CH ₃ ) ₄ and Pb (C ₂ H ₅ ) ₆ . These compounds may be used alone or in combination of two or more.

In the present invention, a desired composition can be controlled by appropriately mixing and using these compounds. As the valence electron controlling agent used for controlling the valence electrons of the Group 4 semiconductor or the Group 4 alloy semiconductor formed in the present invention, as a p-type impurity, an element of Group 3 of the periodic table, for example, B, Preferred examples include Al, Ga, In, Tl, and the like, and examples of the n-type impurity include elements belonging to Group 5 of the periodic table, such as N, P, As, Sb, and Bi. In particular, B, Ga, P, Sb and the like are optimal. The amount of the impurity to be doped is appropriately determined according to desired electrical and optical characteristics.

As such a raw material for introducing impurities, those which are in a gaseous state at normal temperature and normal pressure or which can be easily gasified at least under film forming conditions are employed. As such starting materials for introducing impurities, specifically, PH ₃ , P ₂
H ₄ , PF ₃ , PF ₅ , PCl ₃ , AsH ₃ , AsF ₃ , As
_{F 5, AsCl 3, SbH 3} , SbF 5, BiH 3, BF 3,
BCl ₃ , BBr ₃ , B ₂ H ₆ , B ₄ H ₁₀ , B ₅ H ₉ , B
_{5 H 11, B 6 H 10} , B 6 H 12, AlCl 3 and the like. The compounds containing the above impurity elements may be used alone or in combination of two or more.

In the present invention, the compound containing a Group 2 element of the periodic table, which is used for forming a Group 2 or 6 compound semiconductor, specifically includes Zn (CH ₃ ) ₂ and Zn (C
_{2 H 5) 2, Zn (} OCH 3) 2, Zn (OC 2 H 5) 2, Cd
(CH ₃ ) ₂ , Cd (C ₂ H ₅ ) ₂ , Cd (C ₃ H ₇ ) ₂ , Cd
(C ₄ H ₉ ) ₂ , Hg (CH ₃ ) ₂ , Hg (C ₂ H ₅ ) ₂ , Hg
(C ₆ H ₅ ) ₂ , Hg [C = (C ₆ H ₅ )] _{2 and the} like. Compounds containing elements of Group 6 of the periodic table include, specifically, NO, N ₂ O, CO ₂ , CO, H ₂ S, SCl ₂ ,
_{S 2 Cl 2, SOCl 2,} SeH 2, SeCl 2, Se 2 Br
₂ , Se (CH ₃ ) ₂ , Se (C ₂ H ₅ ) ₂ , TeH ₂ , Te
(CH ₃ ) ₂ , Te (C ₂ H ₅ ) _{2 and the} like.

Of course, these raw materials can be used alone or in combination of two or more.

As the valence electron controlling agent used for controlling the valence electrons of the group 2-6 compound semiconductor formed in the present invention, a compound containing an element of Groups 1, 3, 4, and 5 of the periodic table is effective. Can be cited.

Specifically, compounds containing Group 1 elements include LiC ₃ H ₇ , Li (sec-C ₄ H ₉ ), Li ₂ S,
Li ₃ N and the like can be mentioned as preferable ones.

The compound containing a Group 3 element includes B
_{X 3, B 2 H 6,} B 4 H 10, B 5 H 9, B 5 H 11, B 6 H 10, B
(CH ₃ ) ₃ , B (C ₂ H ₅ ) ₃ , B ₆ H ₁₂ , AlX ₃ , Al
(CH ₃ ) ₂ Cl, Al (CH ₃ ) ₃ , Al (OCH ₃ ) ₃ ,
Al (CH ₃ ) Cl ₂ , Al (C ₂ H ₅ ) ₃ , Al (OC ₂ H
₅ ) ₃ , Al (CH ₃ ) ₃ Cl ₃ , Al (i-C ₄ H ₉ ) ₃ , A
_{l (i-C 3 H 7} ) 3, Al (C 3 H 7) 3, Al (OC
₄ H ₉ ) ₃ , GaX ₃ , Ga (OCH ₃ ) ₃ , Ga (OC
_{2 H 5) 3, Ga (} OC 3 H 7) 3, Ga (OC 4 H 9) 3, G
a (CH ₃ ) ₃ , Ga ₂ H ₆ , GaH (C ₂ H ₅ ) ₂ , Ga
(OC ₂ H ₅ ) (C ₂ H ₅ ) ₂ , In (CH ₃ ) ₃ , In (C ₄
H ₇ ) ₃ , In (C ₄ H ₉ ) ₃ , and compounds containing Group 5 elements include NH ₃ , HN ₃ , N ₂ H ₅ N ₃ , N ₂ H ₄ , NH ₄ N ₃ , P
X ₃ , P (OCH ₃ ) ₃ , P (OC ₂ H ₅ ) ₃ , P (C ₃ H ₇ )
₃ , P (OC ₄ H ₉ ) ₃ , P (CH ₃ ) ₃ , P (C ₂ H ₅ ) ₃ ,
P (C ₃ H ₇ ) ₃ , P (C ₄ H ₉ ) ₃ , P (OCH ₃ ) ₃ , P
(OC ₂ H ₅ ) ₃ , P (OC ₃ H ₇ ) ₃ , P (OC ₄ H ₉ ) ₃ ,
P (SCN) ₃ , P ₂ H4, PH ₃ , AsH ₃ , AsX ₃ ,
As (OCH ₃ ) ₃ , As (OC ₂ H ₅ ) ₃ , As (OC ₃ H
₇ ) ₃ , As (OC ₄ H ₉ ) ₃ , As (CH ₃ ) ₃ , As (C
_{H 3) 3, As (C} 2 H 5) 3, As (C 6 H 5) 3, Sb
X ₃ , Sb (OCH ₃ ) ₃ , Sb (OC ₂ H ₅ ) ₃ , Sb (O
C ₃ H ₇ ) ₃ , Sb (OC ₄ H ₉ ) ₃ , Sb (CH ₃ ) ₃ , Sb
(C ₃ H ₇ ) ₃ , Sb (C ₄ H ₉ ) _{3 and the} like.

In the above, X is a halogen (F, Cl,
Br, I).

Of course, these raw materials may be used alone or in combination of two or more.

Further, as the compound containing a Group 4 element, the compounds described above can be used.

In the present invention, specific examples of the compound containing a Group 3 element of the periodic table used to form a Group 3-5 compound semiconductor include BX ₃ (where X represents a halogen atom), B ₂ H ₆ , B ₄ H ₁₀ , B ₅ H ₉ , B ₅ H ₁₁ , B ₆
H ₁₀ , B ₆ H ₁₂ , AlX ₃ (where X represents a halogen atom), Al (CH ₃ ) ₂ Cl, Al (CH ₃ ) ₃ , Al
(OCH ₃ ) ₃ , Al (CH ₃ ) Cl ₂ , Al (C
_{2 H 5) 3, Al (} OC 2 H 5) 3, Al (CH 3) 3 Cl 3,
_{Al (i-C 4 H 9} ) 3, Al (i-C 3 H 7) 3, Al (C
₃ H ₇ ) ₃ , Al (OC ₄ H ₉ ) ₃ , GaX ₃ (where X represents a halogen atom), Ga (OCH ₃ ) ₃ , Ga (OC
_{2 H 5) 3, Ga (} OC 3 H 7) 3, Ga (OC 4 H 9) 3, G
a (CH ₃ ) ₃ , Ga ₂ H ₆ , GaH (C ₂ H ₅ ) ₂ , Ga
(OC ₂ H ₅ ) (C ₂ H ₅ ) ₂ , In (CH ₃ ) ₃ , In (C ₃
H ₇ ) ₃ and In (C ₄ H ₉ ) ₃ . As the compound containing a Group 5 element of the periodic table, specifically, N
H ₃ , HN ₃ , N ₂ H ₅ N ₃ , N ₂ H ₄ , NH ₄ N ₃ , PX ₃ (where X represents a halogen atom), P (OCH ₃ ) ₃ , P
(OC ₂ H ₅ ) ₃ , P (C ₃ H ₇ ) ₃ , P (OC ₄ H ₉ ) ₃ , P
(CH ₃ ) ₃ , P (C ₂ H ₅ ) ₃ , P (C ₃ H ₇ ) ₃ , P (C _{4
H 9) 3, P (OCH} 3) 3, P (OC 2 H 5) 3, P (OC 3
_{H 7) 3, P (OC} 4 H 9) 3, P (SCN) 3, P 2 H 4, P
H ₃ , AsX ₃ (where X represents a halogen atom), A
sH ₃ , As (OCH ₃ ) ₃ , As (OC ₂ H ₅ ) ₃ , As
(OC ₃ H ₇ ) ₃ , As (OC ₄ H ₉ ) ₃ , As (CH ₃ ) ₃ ,
As (CH ₃ ) ₃ , As (C ₂ H ₅ ) ₃ , As (C ₆ H ₅ ) ₃ ,
SbX ₃ (where X represents a halogen atom), Sb
(OCH ₃ ) ₃ , Sb (OC ₂ H ₅ ) ₃ , Sb (OC
_{3 H 7) 3, Sb (} OC 4 H 9) 3, Sb (CH 3) 3, Sb
(C ₃ H ₇ ) ₃ , Sb (C ₄ H ₉ ) _{3 and the} like. [Where X is a halogen atom, specifically F, Cl, Br, I
Represents at least one selected from Of course, these raw materials can be used alone or in combination of two or more.

As the valence electron controlling agent used for controlling the valence electrons of the group III-V compound semiconductor formed in the present invention, a compound containing an element belonging to groups 2, 4, and 6 of the periodic table is effective. It can be mentioned as. Specifically, 2
Compounds containing group _III elements include Zn (CH ₃ ) ₂ , Zn
(C ₂ H ₅ ) ₂ , Zn (OCH ₃ ) ₂ , Zn (OC ₂ H ₅ ) ₂ ,
Cd (CH ₃ ) ₂ , Cd (C ₂ H ₅ ) ₂ , Cd (C ₃ H ₇ ) ₂ ,
Cd (C ₄ H ₉ ) ₂ , Hg (CH ₃ ) ₂ , Hg (C ₂ H ₅ ) ₂ ,
Hg (C ₆ H ₅ ) ₂ , Hg [C≡C (C ₆ H ₅ )] _{2 and the} like. Examples of the compound containing a Group 6 element include NO,
N ₂ O, CO ₂ , CO, H ₂ S, SCl ₂ , S ₂ Cl ₂ , SO
Cl ₂ , SeH ₂ , SeCl ₂ , Se ₂ Br ₂ , Se (C
_{H 3) 2, Se (C} 2 H 5) 2, TeH 2, Te (CH 3) 2,
Te (C ₂ H ₅ ) _{2 and the} like can be mentioned.

Of course, these raw materials may be used alone or in combination of two or more.

The compounds containing a Group 4 element include the compounds described above.

In the present invention, the starting compound is H
rare gases such as e, Ne, Ar, Kr, Xe, Rn, and H
₂ , mixed with a diluting gas such as HF or HCl, and introduced.

These diluent gases and the like may be independently introduced from gas supply means.

In the method of the present invention, in order to generate and maintain microwave plasma uniformly and stably in the columnar film-forming space, the shape and volume of the film-forming space and the introduction into the film-forming space are required. Although there are optimal conditions for the type and flow rate of the source gas to be used, the pressure in the film formation space, the amount of microwave energy radiated into the film formation space, and the matching of microwaves, these parameters are mutually exclusive. Are organically linked to each other, and are not defined unconditionally, and it is desirable to appropriately set preferable conditions.

That is, according to the method of the present invention, a film-forming space having the band-shaped member as a side wall is formed, and the band-shaped member constituting the side wall of the film-forming space is continuously moved, and the film-forming space is formed. By arranging microwave applicator means to radiate microwave energy almost uniformly in the width direction of the band-shaped member constituting the side wall of the membrane space, and adjusting and optimizing the conditions for generating and maintaining microwave plasma A large-area functional deposition film can be formed continuously and with good uniformity.

The point that the method of the present invention is objectively distinguished from the conventional method of forming a deposited film is that the film forming space has a columnar shape, and the side wall thereof continuously functions, but also functions as a structural material. In addition, it also serves as a substrate or a support for forming a deposited film.

Here, the function as a structural material is, in particular,
This is a function of physically and chemically isolating the atmosphere space for film formation, that is, the film formation space and the atmosphere space not involved in the film formation. Or the function of restricting the direction of gas flow, or forming atmospheres with different pressure differences.

That is, according to the method of the present invention, the band-shaped member is curved to form a side wall of a columnar film-forming space, and the other remaining wall surfaces, that is, both end surfaces and a gap left on a part of the side wall are formed. A source gas for depositing film formation and microwave energy are supplied into the film forming space from any one of the above, and the gas is exhausted to confine microwave plasma in the film forming space. An important function as a structural material for forming a functional deposition film on the band-shaped member constituting the side wall, and the band-shaped member itself isolates the film-forming space from an external atmosphere space not involved in film-forming. And can be used as a substrate or a support for forming a deposited film. Therefore, the atmosphere outside the film formation space configured with the strip-shaped member as a side wall is in a state considerably different from the inside of the film formation space in the gas composition, its state, pressure, and the like.

On the other hand, in the conventional method for forming a deposited film, a substrate or a support for forming a deposited film is disposed in a film forming space for forming a deposited film, and is formed exclusively in the film forming space. For example, it functions only as a member on which a precursor or the like for forming a deposited film is deposited, and does not function as a structural material constituting the film forming space as in the method of the present invention.

In addition, the conventional method of RF plasma CVD
In the method, the sputtering method, etc., the substrate or the support for forming the deposited film may also serve as an electrode for generating and maintaining discharge, but the plasma confinement is insufficient,
The isolation from the external atmosphere space that is not involved in film formation is insufficient, and it cannot be said that it functions as a structural material.

On the other hand, according to the method of the present invention, a band-like member capable of functioning as a substrate or a support for forming a functional deposited film is used as a side wall of the film forming space, and the function as the structural material is exhibited. This also enables continuous formation of a functional deposition film on the belt-shaped member.

In the method of the present invention, the side wall of the columnar space is formed by using the band-shaped member, and the microwave energy is radiated almost uniformly in the width direction of the band-shaped member into the columnar space. By confining the microwave in the space, the microwave energy is efficiently consumed in the columnar space, a uniform microwave plasma is generated, and the uniformity of the deposited film to be formed is increased. Further, the belt-like member constituting the side wall exposed to the microwave plasma is continuously moved and discharged out of the film forming space, so that the band-like member has uniformity in the moving direction. High deposited film can be formed.

In the method of the present invention, the gas composition and the state outside the film formation space are the same as those described above so that a film formation space is formed by the strip-shaped member and a deposited film is formed only in the film formation space. Conditions are set to be different from those in the membrane space. For example, the gas composition outside the film formation space may be a gas atmosphere not directly involved in the formation of a deposited film, or may be an atmosphere containing a source gas discharged from the film formation space. Further, it is needless to say that the microwave plasma is confined in the film formation space, but the microwave plasma is not leaked to the outside of the film formation space. It is also effective in improving reproducibility and preventing film deposition on unnecessary parts. Specifically, a pressure difference is applied between the inside and outside of the film formation space, an atmosphere of a so-called inert gas having a small ionization cross section, H ₂ gas or the like is formed, or a microwave is positively applied from the inside of the film formation space. It is effective to provide a means that does not cause leakage. As means for preventing microwave leakage, a gap portion connecting the inside and the outside of the film forming space is sealed with a conductive member, or the hole diameter is preferably 波長 wavelength or less, more preferably 波長 wavelength of the microwave used. It may be covered with the following metal mesh or punching board, and the maximum dimension of the gap connecting the inside and the outside of the film forming space is preferably 波長 wavelength or less, more preferably １ ／ wavelength or less of the wavelength of microwave. It is desirable. Also, by setting the pressure outside the film formation space to be very low compared to the pressure inside the film formation space, or conversely, setting it high, microwave plasma is generated outside the film formation space. You can set conditions that do not.

As described above, the method of the present invention is characterized in that the band-shaped member has a function as a structural material constituting a film-forming space, and is distinguished from the conventional method of forming a deposited film. Bring effect.

Hereinafter, the microwave plasma CVD of the present invention will be described.
The configuration and features of the apparatus will be described in more detail step by step.

According to the apparatus of the present invention, since the microwave plasma region is confined by the moving belt-like member, the precursor contributing to the formation of the deposited film generated in the microwave plasma region can be obtained at a high yield. Thus, the efficiency of use of the source gas for forming a deposited film can be dramatically increased because the deposited film can be continuously captured on the substrate and the deposited film can be continuously formed on the belt-shaped member.

Further, since uniform microwave plasma is generated in the film forming space by using the microwave applicator means of the present invention, the uniformity of the deposited film formed in the width direction of the belt-like member is improved. As a matter of course, the belt-shaped member is conveyed continuously in a direction substantially perpendicular to the longitudinal direction of the microwave applicator means, so that the deposited film formed in the longitudinal direction of the belt-shaped substrate is made uniform. It also has excellent properties.

Further, according to the apparatus of the present invention, since the discharge can be maintained stably and uniformly, a functional deposition film having stable characteristics can be continuously formed on a long strip-shaped member. In addition, a laminated device having excellent interface characteristics can be manufactured.

In the apparatus of the present invention, when the band-shaped member is made to function as a structural material, the outside of the film formation chamber may be air, but the function formed by the inflow of air into the film formation chamber may be formed. If the characteristics of the conductive deposited film are affected, an appropriate air inflow prevention means may be provided. Specifically, an O-ring, a gasket, a helicflex, a mechanical sealing structure using a magnetic fluid, or the like, or a diluent gas atmosphere that has little or no effect on the characteristics of the deposited film to be formed, or It is desirable to dispose an isolation container for forming an appropriate vacuum atmosphere around the container. In the case of the mechanical sealing structure, special care needs to be taken so that the sealing state can be maintained while the belt-shaped member moves continuously. In the case where the apparatus of the present invention is connected to a plurality of other deposited film forming means and a deposited film is continuously stacked on the belt-shaped member, it is desirable to connect the respective apparatuses using gas gate means. In the case where only a plurality of the apparatuses of the present invention are connected, the film forming chamber is an independent film forming atmosphere in each apparatus. Therefore, the isolation container may be single or may be provided in each apparatus. good.

In the apparatus of the present invention, the pressure outside the film forming chamber may be in a reduced pressure state or a pressurized state. What is necessary is just to arrange | position the auxiliary | assistant structural material in said film-forming chamber. As the auxiliary structure material, it is desirable that the shape substantially the same as the side wall of the film forming chamber is formed of a wire, a thin plate, or the like made of metal, ceramics, reinforced resin, or the like having appropriate strength. . In addition, since the auxiliary film is hardly formed on the belt-like member facing the surface of the auxiliary structure that is not exposed to the microwave plasma, the auxiliary structure is hardly shadowed. It is desirable that the projection area of the material on the strip is designed to be as small as possible.

Further, the mesh pattern or the like provided on the auxiliary structural member is formed by bringing the auxiliary structural member into close contact with the band-shaped member and rotating or moving the auxiliary structural member in synchronization with the transport speed of the band-shaped member. It can also be formed on a member.

As the material of the belt-like member suitably used in the method and the apparatus of the present invention, microwave plasma C
Deformation and distortion are small at the temperature required at the time of forming the functional deposition film by the VD method, and have a desired strength.
It is preferable to have conductivity, and specifically, a thin plate of a metal such as stainless steel, aluminum and its alloys, iron and its alloys, copper and its alloys and a composite thereof, and dissimilar materials on their surfaces Metal thin film and / or
Alternatively, an insulating thin film of SiO ₂ , Si ₃ N ₄ , Al ₂ O ₃ , AlN or the like is subjected to a surface coating treatment by a sputtering method, a vapor deposition method, a plating method, or the like. In addition, the surface of a heat-resistant resin sheet such as polyimide, polyamide, polyethylene terephthalate, epoxy, or a composite of these with glass fiber, carbon fiber, boron fiber, metal fiber, or the like, may be a simple metal or alloy, and a transparent conductive oxide. (TCO) or the like that has been subjected to a conductive treatment by a method such as plating, vapor deposition, sputtering, or coating.

The thickness of the belt-like member can be set in consideration of cost, storage space, and the like, as long as the thickness is within a range in which the curved shape formed at the time of carrying by the carrying means exhibits strength for maintaining the same. It is desirable to be as thin as possible. Specifically, it is preferable that the thickness is preferably 0.01 mm to 5 mm, more preferably 0.02 mm to 2 mm, and most preferably 0.05 mm to 1 mm. The desired strength can be easily obtained even if the thickness is reduced. Further, the width dimension of the band-shaped member may be such that, when the microwave applicator is used, uniformity of the microwave plasma with respect to the longitudinal direction is maintained, and the curved shape is maintained. Preferably, specifically, preferably 5 cm to 100 c
m, more preferably 10 cm to 80 cm.

The length of the belt-like member is not particularly limited, and may be a length that can be wound into a roll. It may be what you did.

In the apparatus of the present invention, the means for supporting and transporting the belt-like member while continuously bending the belt-like member may be such that the belt-like member has a curved shape without causing slack, wrinkles, lateral displacement or the like during the transportation. It is necessary to keep it constant. For example, at least one pair of support / transport rings having a desired curved shape is provided, and preferably both ends of the belt-shaped member are supported by the support / transport ring, and the belt is curved along the shape, and further, the belt-shaped member is bent. At least a pair of support / transport rollers provided in the longitudinal direction of the member as a curving start end forming means and a curving end end forming means are squeezed and bent into a substantially columnar shape. A driving force is applied to at least one of the rollers for transporting the belt-shaped member in its longitudinal direction while maintaining a curved shape. In addition, as a method of supporting and transporting the belt-shaped member by the support / transport ring, only sliding friction may be used, or a process such as a sprocket hole may be performed on the belt-shaped member, and the support / transport ring may be used. Also, a so-called gear-shaped one having a saw-tooth-shaped projection provided around it may be used.

Regarding the shape of the support / transport ring, it is preferable that the shape be a circular shape in order to form a curved shape. However, even if the shape is an elliptical shape, a square shape, or a polygonal shape, it is continuously constant. There is no particular problem as long as it has a mechanism for maintaining the shape. Maintaining a constant transport speed is an important point in transporting the curved shape without causing slack, wrinkles, lateral displacement and the like. Therefore, it is desirable that the support / transport mechanism is provided with a transport speed detecting mechanism for the belt-shaped member and a transport speed adjusting mechanism to which a field-back is applied. Also,
These mechanisms have a great effect on controlling the film thickness in manufacturing a semiconductor device. In addition, the support
The transport ring will be disposed in the microwave plasma region, although the degree of exposure to the plasma will vary for that purpose. Therefore, a material that can withstand microwave plasma, that is, a material having excellent heat resistance, corrosion resistance, etc., is desirable. In addition, a deposited film adheres to the surface thereof, and the deposited film adheres during a long-time deposition operation. The film is peeled off and scattered, and adheres to the deposited film being formed, causing defects such as pinholes in the deposited film, and consequently the characteristics of the manufactured semiconductor device and the yield are reduced. Therefore, it is desirable that the deposited film be made of a material having a low adhesion coefficient or a material and surface shape capable of maintaining a strong adhesive force up to a considerable film thickness even if adhered. Specific materials include those processed using stainless steel, nickel, titanium, vanadium, tungsten, molybdenum, niobium and alloys thereof, or alumina, quartz, magnesia, zirconia, silicon nitride, boron nitride, nitrided on the surface thereof. Examples thereof include those obtained by coating a ceramic material such as aluminum by a thermal spraying method, a vapor deposition method, a sputtering method, an ion plating method, a CVD method, or the like, or a material formed by processing a single or composite of the ceramic material. . The surface shape is appropriately selected in consideration of the stress of the film to be deposited, such as mirror finishing and unevenness processing.

The deposited film adhering to the support / transport ring is preferably removed before peeling, scattering, etc. occur. Desirably, it is removed by physical means.

The support / transport roller is provided with the support / transport roller.
Since the area in contact with the band-shaped member is designed to be larger than that of the transfer ring, the heat exchange rate with the band-shaped member is large. Therefore, it is desirable to have a mechanism for appropriately adjusting the temperature so that the temperature of the belt-shaped member is not extremely increased or decreased by the supporting / transporting roller. However, at least one pair of support
The set temperature of the transport roller may be different. Further, the support / transport roller has a built-in transport tension detecting mechanism for the belt-shaped member, which is also effective in keeping the transport speed constant.

Furthermore, it is preferable that the support / transport roller is provided with a crown mechanism for preventing the belt-shaped member from bending, twisting, laterally displacing or the like during the transport. The curved shape formed in the present invention is formed in a columnar shape so as to partially include the tip portion of the applicator means.

The shape of the both end surfaces of the columnar film forming chamber formed by using the strip-shaped member as a side wall is substantially circular, elliptical, square, polygonal or the like, and the microwave applicator means is arranged. It is desirable that the position is provided substantially in the vicinity of the center of the shape in order to uniformly generate microwave plasma in the film forming chamber and to improve the uniformity of the formed deposited film. Further, the inner diameter of the end face of the curved portion determines the microwave transmission mode and the volume of the microwave plasma region, and substantially correlates with the time during which the band-shaped member is exposed to the microwave plasma region during transportation. The film thickness of the deposited film formed is determined, and the area ratio of the side wall to the inner surface area of the film forming chamber is determined in correlation with the width dimension of the strip-shaped member. It is determined. In the microwave plasma region, the microwave power density (W / cm ³ ) for maintaining stable microwave plasma depends on the type and flow rate of the raw material gas used, the pressure, the microwave radiation of the microwave applicator, It is determined by the correlation between the transmission capacity and the absolute volume of the microwave plasma region, and it is difficult to unambiguously define it.

When the band-shaped member is used as a substrate for a solar cell, if the band-shaped member is electrically conductive such as a metal, it may be used as an electrode for directly taking out current, or an electric insulating material such as a synthetic resin. In the case of the property, Al, Ag, Pt, Au, Ni, Ti, M
o, W, Fe, V, Cr, Cu, stainless steel, brass, _{nichrome, SnO 2, In 2 O 3} , ZnO, SnO 2 -
A so-called single metal or alloy such as In ₂ O ₃ (ITO) or a transparent conductive oxide (TCO) is subjected to surface treatment in advance by plating, vapor deposition, sputtering, or the like to form an electrode for current extraction. It is desirable.

Of course, even if the strip-shaped member is made of an electrically conductive material such as a metal, the reflectance of long-wavelength light on the surface of the substrate can be improved, and the constituent elements between the substrate material and the deposited film can be improved. A different kind of metal layer or the like may be provided on the side of the substrate on which the deposited film is formed, for the purpose of preventing mutual diffusion of the layers and forming an interference layer for preventing short circuit. When the band-shaped member is relatively transparent and a solar cell having a layer configuration in which light is incident from the side of the band-shaped member, a conductive thin film such as the transparent conductive oxide or a metal thin film is previously deposited. It is desirable to form it.

The surface of the belt-like member may be a so-called smooth surface or a fine uneven surface.
In the case of a minute uneven surface, the uneven shape is spherical, conical, pyramidal, or the like, and its maximum height (Rmax)
Is preferably 500 ° to 5000 °, the light reflection on the surface becomes irregular reflection, and the optical path length of the reflected light on the surface is increased.

The microwave permeable member is provided at the tip of the microwave applicator means, and separates the vacuum atmosphere in the film forming chamber from the outside air in which the microwave applicator means is installed. Designed to withstand existing pressure differences. Specifically, the cross-sectional shape of the microwave in the traveling direction is preferably circular, square, elliptical flat plate, bell jar,
Desirably, it has a doublet shape and a conical shape.

The thickness of the microwave permeable member in the direction in which the microwave travels is designed in consideration of the dielectric constant of the material used so that the reflection of the microwave here is minimized. Preferably, for example, in the case of a flat plate, it is preferable that the wavelength is substantially equal to a half wavelength of the microwave. Further, the material is such that microwave energy radiated from the microwave applicator means can be transmitted into the film forming chamber with a minimum loss, and airtightness does not occur in the air flowing into the film forming chamber. Are preferred, specifically, quartz, alumina, silicon nitride, beryllia, magnesia, zirconia,
Glass such as boron nitride and silicon carbide, fine ceramics, and the like are included.

Further, it is preferable that the microwave permeable member is uniformly cooled in order to prevent heat deterioration (crack, destruction) or the like due to heating by microwave energy and / or plasma energy.

As a specific cooling means, a cooling air flow blown toward the atmosphere-side surface of the microwave permeable member may be used, or the microwave applicator means may be cooled air, water, or the like. The microwave-permeable member may be cooled by a cooling medium such as oil or freon, and cooled through a portion in contact with the microwave applicator means. By cooling the microwave permeable member to a sufficiently low temperature, even if microwave energy of relatively high power is introduced into the film forming chamber, the generated heat may cause the microwave permeable member to have cracks or the like. A high electron density plasma can be generated without causing destruction.

Further, in the apparatus of the present invention, film deposition occurs on the portion where the microwave permeable member is in contact with the microwave plasma as on the strip-shaped member. Therefore,
Although it depends on the type and characteristics of the film to be deposited, microwave energy to be radiated from the microwave applicator means is absorbed or reflected by the deposited film, and microwaves into the film forming chamber formed by the band-shaped member are absorbed. If the amount of energy radiation decreases and the amount of change increases significantly compared to immediately after the start of discharge, not only is it difficult to maintain the microwave plasma itself, but also the deposition rate of the deposited film decreases. And changes in characteristics and the like. In such a case, the initial state can be restored by removing the film deposited on the microwave transmitting member by dry etching, wet etching, a mechanical method, or the like. In particular, dry etching is preferably used as a method for removing the deposited film while maintaining the vacuum state.

Further, while keeping the vacuum state in the film forming chamber together with the microwave applicator means, the film is taken out of the film forming chamber by a so-called load lock method and the film deposited on the microwave permeable member is subjected to wet etching or It may be separated and reused by mechanical removal or the like, or may be replaced with a new one. Further, by continuously feeding a sheet made of a material having a microwave permeability substantially equivalent to that of the microwave permeable member along the surface of the microwave permeable member on the film forming chamber side, It is also possible to adopt a method in which a deposited film is adhered and formed on the surface of the sheet, and is discharged out of the microwave plasma region.

The microwave applicator means in the apparatus of the present invention radiates microwave energy supplied from a microwave power supply into the film forming chamber, and converts a raw material gas for forming a deposited film introduced from the gas introducing means into a plasma. It has a structure that can be changed and maintained.

Specifically, it is preferable to use the microwave transmission waveguide in which the microwave transmitting member is attached to the distal end portion of the waveguide in a state capable of maintaining airtightness. The microwave applicator means may be of the same standard as the microwave transmission waveguide, or may be of another standard. The microwave transmission mode in the microwave applicator means enables efficient transmission of microwave energy in the film forming chamber and stably generates, maintains, and controls microwave plasma. Therefore, it is desirable that the size, shape, and the like of the microwave applicator are designed to be a single mode. However, even when a plurality of modes are transmitted, they can be used by appropriately selecting microwave plasma generation conditions such as a source gas, pressure, and microwave power to be used. The transmission mode when it is designed to be single mode, for example, TE ₁₀ mode, TE ₁₁ mode, eH ₁ mode, TM ₁₁ mode, T
_M01 mode party, but preferably TE
₁₀ mode, TE ₁₁ mode, and eH ₁ mode are selected.
A waveguide capable of transmitting the above-mentioned transmission mode is connected to the microwave applicator means. Preferably, the transmission mode in the waveguide and the transmission mode in the microwave applicator means coincide with each other. Is desirable.
The type of the waveguide is appropriately selected depending on the frequency band (band) and mode of the microwave used, and it is preferable that at least the cut-off frequency is lower than the frequency used. JI
S, EIAJ, IEC, JAN, etc. standard rectangular waveguide,
In addition to a circular waveguide, an elliptical waveguide, and the like, as a company standard for microwaves of 2.45 GHz, there can be cited one having a square cross section having an inner diameter of 96 mm and a height of 27 mm.

In the apparatus of the present invention, the microwave energy supplied from the microwave power source is efficiently radiated into the film forming chamber through the microwave applicator means, so that the reflected wave caused by the so-called microwave applicator is used. Is relatively easy to avoid, and in a microwave circuit, a relatively stable discharge can be maintained without using a microwave matching circuit such as a three-stub tuner or an EH tuner. If a strong reflected wave is generated due to abnormal discharge or the like even after the start, it is desirable to provide the microwave matching circuit to protect the microwave power supply.

It is desirable that the number of gas supply means provided in the apparatus of the present invention is at least equal to or greater than the number of component elements of the functional deposition film to be formed. Each of the gas supply means is constituted by a pipe-shaped gas introduction pipe, and one or more rows of gas discharge ports are opened on the side surfaces thereof. As the material constituting the gas introduction tube, a material that is not damaged in microwave plasma is preferably used. Specifically, heat-resistant metals such as stainless steel, nickel, titanium, niobium, tantalum, tungsten, vanadium, and millibden, and those obtained by spraying these on ceramics such as alumina, silicon nitride, and quartz; and alumina, silicon nitride, Examples thereof include ceramics such as quartz and those composed of a composite.

[0177] In the apparatus of the present invention, the gas supply means is provided in parallel with the width direction of the band-shaped member constituting the side wall of the film forming chamber, and the gas discharge port is directed to the adjacent band-shaped member.

The arrangement of the gas supply means used in the apparatus of the present invention will be specifically described below with reference to the drawings.
It is not particularly limited to these.

FIGS. 7 and 8 are schematic side sectional views showing the arrangement of gas introduction pipes in the apparatus of the present invention. In this drawing, only main constituent members are shown.

In the example shown in FIG. 7, three gas introduction pipes 113a and 113
This is a typical example in the case where 3b and 113c are provided, and the pipe-shaped gas introduction pipes 113a, 113b and 113c are located at substantially equal distances from the center O of the film forming chamber 116, respectively.
As shown in the figure, H ′ is used as a reference and arranged at angles θ ₃ , θ ₄ , and θ ₅ in parallel with the width direction of the belt-shaped member 101. Then, the gas discharge ports 701a, 701b, 701c
Are directed to the adjacent strip-shaped members 101, respectively.

In this arrangement, the gas introduction tube 113b is arranged on the center line HH 'of the film formation chamber 116, but may be arranged at any position shifted to the left or right as desired. Also, the center O of the gas introduction pipes 113a, 113b, 113c
May be equal to each other or different from each other. The angles θ ₃ , θ ₄ , θ ₅ may again be equal or different.

Gas introduction pipes 113a, 113b, 113c
The raw material gases for forming a deposited film, which are appropriately mixed as required, are introduced into each of the above while independently controlled.

Gas outlets 701a, 701b, 701c
Are arranged in a row on the side surface of each gas introduction pipe at substantially equal intervals, but are spaced in order to improve the uniformity in the width direction of the deposited film to be formed according to the increase or decrease in the gas introduction amount. May be appropriately changed.

Of course, even if the number of gas introduction pipes is two,
The number may be four or more.

In the example shown in FIG. 8, two gas introduction pipes 703a and 703a as gas supply means are provided in a columnar film forming chamber.
This is a typical example in a case where a gas flow plate 3b and a gas flow regulating plate 702 are provided. The gas introduction pipes 703a, 703b are
Are arranged almost symmetrically. Gas inlet pipe 7 if desired
The distances 03a and 703b from the gas flow regulating plate may be changed. By disposing the gas rectifying plate 702, the separation of the deposition film forming source gas discharged from each gas introduction pipe in the film formation chamber is improved, and the composition controllability of the formed deposition film is improved.

The size, shape, location, and the like of the gas rectifying plate are appropriately determined according to the desired composition of the deposited film.

The number of gas introduction pipes may be two or three or more.

The gas outlet is opened similarly to the gas inlet tube used in FIG.

In the apparatus of the present invention, in order to control the plasma potential of the microwave plasma generated in the film forming chamber,
A bias voltage may be applied to the gas introduction pipe. The bias voltages applied to the plurality of gas introduction tubes may be equal to each other, or may be different from each other. As the bias voltage, it is desirable to apply a DC, a pulsating current, and an AC voltage alone or by superimposing each of them.

To apply a bias voltage effectively,
It is desirable that the surfaces of both the gas introduction pipe and the belt-shaped member are conductive.

By controlling the plasma potential by applying a bias voltage, it is possible to improve plasma stability, reproducibility, film characteristics, and suppress the occurrence of defects.

In the apparatus of the present invention, part or all of the deposited film forming raw material gas introduced into the columnar film forming chamber from the gas introduction pipe is decomposed to generate a deposited film forming precursor. A deposited film is formed, but undecomposed raw material gas,
Alternatively, a gas having a different composition due to decomposition must be immediately exhausted to the outside of the columnar film forming chamber. However, if the area of the exhaust hole is made unnecessarily large, microwave energy leaks from the exhaust hole, causing instability of plasma or adversely affecting other electronic devices, the human body, and the like. . Therefore, in the device of the present invention, the exhaust hole is a gap between the bending start end and the bending end end of the band-shaped member, and the gap is preferably the wavelength of the microwave used to prevent microwave leakage. It is desirable that the wavelength be equal to or less than 1/2 wavelength, and more preferably equal to or less than 1/4 wavelength.

In the apparatus of the present invention, a gap is left between the bending start end forming means and the bending end end forming means in the film forming chamber, and the raw material gas is exhausted from the gap.
The film forming chamber is maintained at a predetermined reduced pressure state, but the size of the gap is such that a sufficient exhaust conductance is obtained, and at the same time, the microwave energy radiated into the film forming chamber is out of the film forming chamber. It needs to be designed not to leak.

Specifically, the direction of the electric field of the microwave propagating in the microwave applicator means, the center axis of the supporting / transporting roller as the bending start end forming means, and the support / transporting roller as the bending end end forming means. The microwave applicator means is arranged so that the plane including the central axis of the transport roller is not parallel to each other. That is,
The waveguide connected to the microwave applicator means is arranged such that a surface including a long side or a long axis of the waveguide and a surface including a central axis of the pair of supporting / transporting rollers are not parallel to each other. Arrange.

If microwave energy is to be radiated into the film forming chamber through a plurality of the microwave applicator means, it is necessary that each of the microwave applicator means is disposed as described above. .

Further, the maximum size of the opening width in the longitudinal direction of the band-like member in the gap left between the bending start end forming means and the bending end end forming means prevents the leakage of microwave energy from the gap. In order to prevent this, it is desirable that the wavelength of the microwave is preferably 好 ま し く wavelength or less, more preferably １ ／ wavelength or less.

In the apparatus of the present invention, when a plurality of the microwave applicator means are disposed so as to face each other, the microwave energy radiated from one microwave applicator means is used for the other microwave applicator means. Received, the received microwave energy reaches the microwave power supply connected to the other microwave applicator means, and damages the microwave power supply or causes an abnormality in microwave oscillation. It is necessary to arrange them so as not to cause adverse effects such as the above.

More specifically, the microwave applicator means is provided so that the directions of electric fields of the microwaves traveling in the microwave applicator means are not parallel to each other. That is, the waveguide is arranged such that the long side or the plane including the long axis of the waveguide connected to the microwave applicator means is not parallel to each other.

In the method of the present invention, when microwave energy is emitted from only one of the two end faces of the film forming chamber, it is necessary to prevent microwave energy from leaking from the other end face. It is desirable to seal the end face with a conductive member, or cover the end face with a wire mesh having a hole diameter of preferably 以下 wavelength or less, more preferably １ ／ wavelength or less, a punching board or the like.

In the apparatus of the present invention, the film forming chamber and / or
Alternatively, gas gate means is preferably used to separate and separate the vacuum vessel and the vacuum vessel having another film forming means from the vacuum chamber and to continuously transport the belt-shaped member through them. In the apparatus of the present invention, it is desirable that the inside of the film forming chamber and / or the isolation vessel is maintained at a low pressure necessary for operation near the minimum value of the modified Paschen curve. In many cases, the pressure in another vacuum vessel to be connected is at least substantially equal to or higher than the pressure. Therefore, it is necessary for the gas gate means to have a capability of preventing the mutually used deposition film forming source gases from diffusing due to a pressure difference generated between the containers. Accordingly, the basic concept is described in U.S. Pat. No. 4,438,7.
Although the gas gating means disclosed in No. 23 can be employed, its capacity needs to be further improved. Specifically, it is necessary to be able to withstand a pressure difference of about 10 ⁶ times at the maximum, and an oil diffusion pump, a turbo molecular pump, a mechanical booster pump, or the like having a large exhaust capacity is preferably used as the exhaust pump. Further, the cross-sectional shape of the gas gate is a slit shape or a shape similar thereto,
These dimensions are calculated and designed by using a general conductance calculation formula together with the overall length and the exhaust capacity of the exhaust pump to be used. Further, it is preferable to use a gate gas in combination to enhance the separation ability.
A rare gas such as e, Ne, Kr, Xe, and Rn, or a diluent gas for forming a deposited film such as H ₂ . The gate gas flow rate is appropriately determined depending on the conductance of the entire gas gate, the capacity of the exhaust pump used, and the like.
What is necessary is just to form the pressure gradient as shown in FIG. In FIG. 25, there is a point where the pressure is maximum at substantially the center of the gas gate. Therefore, the gate gas flows from the center of the gas gate to the vacuum vessels on both sides, and in FIG. 26, the pressure becomes minimum at the substantially center of the gas gate. Since there is a point, the gate gas is also exhausted from the central part of the gas gate together with the source gas for forming the deposited film flowing from the containers on both sides. Therefore, in both cases, mutual gas diffusion between the containers on both sides can be minimized. In practice, the optimum conditions are determined by measuring the amount of gas diffused using a mass spectrometer or by analyzing the composition of the deposited film.

[0201] In the apparatus of the present invention, the deposition film forming means provided in the other vacuum vessel connected to the isolation vessel by the gas gate means may be an RF plasma C.
VD method, sputtering method and reactive sputtering method, ion plating method, optical CVD method, thermal CVD
Means for realizing a method used for forming a so-called functional deposited film, such as a method, MOCVD method, MBE method, and HR-CVD method. And, of course, it is also possible to connect means of the microwave plasma CVD method of the present invention and a similar microwave plasma CVD method, select an appropriate means for manufacturing a desired semiconductor device, and connect using the gas gate means. Is done.

The microwave frequency supplied from the microwave power supply used in the apparatus of the present invention is preferably 2.45 GHz which is used for consumer use. Any material that is easily available can be used. Further, in order to obtain a stable discharge, the oscillation mode is desirably a so-called continuous oscillation, and its ripple width is preferably within 30%, more preferably within 10% in a used output region.

In the apparatus of the present invention, the film forming chamber and / or
Alternatively, it is effective to form a deposited film continuously without exposing the isolation container to the atmosphere because the deposited film can be prevented from being mixed with impurities in terms of stable characteristics. However, since the length of the band-shaped member used is limited, it is necessary to perform an operation of connecting the band-shaped member by processing such as welding.
Specifically, such a processing chamber may be provided in the vicinity of the container (the sending side and the winding side) in which the band-shaped member is stored.

[Examples of Apparatus] Hereinafter, specific examples of the present invention will be described with reference to the drawings, but the present invention is not limited to these examples.

Apparatus Example 1 FIG. 1 is a schematic perspective schematic view of a microwave plasma CVD apparatus of the present invention.

Reference numeral 101 denotes a belt-like member, which includes support / transport rollers 102 and 103, a support / transport ring 104,
The film is conveyed in the direction of the arrow (→) in FIG. Reference numerals 106a to 106e denote temperature control mechanisms for heating or cooling the belt-shaped member 101, and the temperature is controlled independently of each other.

In this example of the apparatus, a pair of microwave applicators 107 and 108 are provided so as to face each other, and microwave transmitting members 109 and 110 are provided at their tip portions, respectively. 111, 112
Are arranged such that the planes including the long sides thereof are not perpendicular to the planes including the center axis of the supporting / transporting rollers, and the planes including the long sides are not parallel to each other. . In FIG. 1, the microwave applicator 107 is shown separated from the support / transport ring 104 for the purpose of explanation, but is arranged in the direction of the arrow in the figure when forming a deposited film.

Reference numerals 113a, 113b, and 113c denote gas introduction pipes, into which a raw material gas for forming a deposited film is independently introduced via a mass flow controller (not shown). When applying a bias voltage for plasma potential control,
A voltage may be applied to the gas introduction pipe from a DC or AC power supply via a conductor. At this time, it is desirable to insert an insulating joint into a part of the gas introduction pipe so that a bias voltage is applied only to the film formation space side. An exhaust pipe 114 is connected to an exhaust pump (not shown). 11
Reference numerals 5a and 115b denote isolation passages, which are provided when the apparatus of the present invention is connected to a container or the like including other film forming means.

The support / transport rollers 102 and 103 incorporate a transport feed detecting mechanism and a tension detecting and adjusting mechanism (both are not shown) to keep the transport feed of the belt-shaped member 101 constant and to adjust its curved shape. Is kept constant.

A microwave power supply (not shown) is connected to the waveguides 111 and 112.

FIG. 2 shows the microwave applicator means 10.
7 and 108 are schematic sectional views for specifically explaining the same.

A microwave applicator 200 transmits microwaves from a microwave power supply (not shown) via a rectangular waveguide 208 from the left arrow direction in the figure.

Numerals 201 and 202 are microwave transmitting members, which are fixed to the inner cylinder 204 and the outer cylinder 205 using a metal seal 212 and a fixing ring 206, and are vacuum-sealed. A cooling medium 209 flows between the inner cylinder 204 and the outer cylinder 205, and one end is sealed with an O-ring 210 to uniformly cool the entire microwave applicator 200. I have. As the cooling medium 209, water, freon, oil, cooling air and the like are preferably used. The microwave permeable member 201 has microwave matching disks 203a, 20
3b is fixed. A choke flange 207 having a groove 211 is connected to the outer cylinder 205. 213 and 214 are cooling air introduction holes and / or discharge holes, which are used to cool the inside of the applicator.

In this example of the apparatus, the inner shape of the inner cylinder 204 is cylindrical, and the inner diameter and the length of the microwave in the traveling direction are designed to function as a waveguide. That is, the inner diameter is smaller than the frequency of the microwave used for the cutoff frequency, and is as large as possible within a range in which a plurality of modes do not stand, and the length of the standing wave is preferably within the range. It is desirable that it be designed to have a length that is not too long. Of course, the inner cylinder 20
The shape inside 4 may be prismatic.

Apparatus Example 2 In this apparatus example, there can be mentioned a case where the apparatus shown in Apparatus Example 1 is disposed in an isolated container.

The shape of the isolation container is not particularly limited as long as it can incorporate each of the constituent jigs shown in Example 1 of the apparatus, but a cubic shape, a rectangular parallelepiped shape, a cylindrical shape, or the like is preferably used. Can be An auxiliary gas introduction pipe is provided in a space left between the film formation chamber 116 and the isolation container, and a rare gas, a H ₂ gas, and the like for adjusting pressure for preventing discharge in the space are introduced. . Further, the space may be simultaneously evacuated by an exhaust pump of the film forming chamber 116, or an independent exhaust pump may be connected.

Apparatus Example 3 In this apparatus example, the same configuration as that of the apparatus example 1 except that the shape of the microwave applicator is changed to a prismatic shape can be mentioned. The cross-sectional dimensions of the prismatic microwave applicator may be the same as or different from the dimensions of the waveguide used. Further, it is desirable to increase the frequency of the microwave used as much as possible within a range in which a plurality of modes do not stand.

Apparatus Example 4 This apparatus example has the same configuration as the apparatus example 2 except that the prismatic microwave applicator means used in the apparatus example 3 is used.

Apparatus Examples 5 and 6 In this apparatus example, the same configuration as in Apparatus Examples 1 and 2 except that an elliptic cylindrical microwave applicator is used instead of the cylindrical microwave applicator is used. it can.

Apparatus Example 7 In this apparatus example, as shown in FIG. 3, vacuum containers 301 and 302 for feeding and winding the belt-like member 101 to the microwave plasma CVD apparatus for forming a deposited film shown in Apparatus Example 2. Are connected using gas gates 321 and 322.

In this example of the apparatus, the gas supply means having the structure shown in FIG. 7 is provided. Of course, the gas supply means having the structure shown in FIG. 8 or other gas supply means is provided. Is also good.

Reference numeral 300 denotes a distance container, 303 denotes a feeding bobbin for a belt-like member, and 304 denotes a bobbin for winding the belt-like member. The belt-like member is conveyed in the direction of the arrow in the figure. Of course, this can be reversed and transported. In the vacuum containers 301 and 302, means for winding and feeding interleaving paper used for protecting the surface of the belt-shaped member may be provided. As the material of the interleaving paper, polyimide, Teflon, glass wool, or the like, which is a heat-resistant resin, is preferably used. Reference numerals 306 and 307 denote conveying rollers that also serve to adjust the tension and position the belt-shaped member. 312, 313
Is a temperature adjusting mechanism used for preliminary heating or cooling of the belt-shaped member. Reference numerals 307, 308, and 309 denote throttle valves for adjusting the displacement, and 310, 311, and 320 denote exhaust pipes, each of which is connected to an exhaust pump (not shown).
Reference numerals 314 and 315 denote pressure gauges, reference numerals 316 and 317 denote gate gas introduction pipes, and reference numerals 318 and 319 denote gate gas exhaust pipes. The exhaust gas (not shown) exhausts the gate gas and / or the source gas for forming a deposited film.

Apparatus Example 8 In this apparatus example, as shown in FIG. 4, the isolation apparatus 300-a in which two additional deposition film forming apparatuses by microwave plasma CVD are incorporated in the apparatus shown in the apparatus example 7 is used. , 30
Ob may be connected to both sides to form a stacked device. Each of the two connected deposited film forming apparatuses is provided with one gas introduction pipe.

In this example of the apparatus, the deposited film forming apparatus built in the isolation container 300 is provided with the gas supply means having the structure shown in FIG. 7, but of course the gas supply means having the structure shown in FIG. Alternatively, a gas supply unit having another configuration may be provided.

[0225] In the figure, those denoted by reference numerals a and b are mechanisms having basically the same effects as those used in the isolation container 300.

Reference numerals 401, 402, 403, and 404 denote gas gates, 405, 406, 407, and 408 denote gate gas introduction pipes, and 409, 410, 411, and 412 denote gate gas exhaust pipes, respectively.

Apparatus Examples 9 and 10 In Apparatus Examples 7 and 8, the microwave applicator 20 was used.
One having the same configuration except that 1 was changed to the prismatic microwave applicator used in Apparatus Example 3 or 4 can be mentioned.

Apparatus Examples 11 and 12 Examples may be the same as in Apparatus Examples 7 and 8 except that the microwave applicator is changed to the elliptic columnar microwave applicator used in Apparatus Examples 5 and 6.

Apparatus Example 13 In this apparatus example, as shown in FIG. 5, two RF plasma CVD apparatuses, which are a conventional method, are connected to both sides of the apparatus shown in Apparatus Example 7 to produce a stacked device. One that can be used is exemplified.

[0230] In this example of the apparatus, the gas supply means having the structure shown in Fig. 7 is provided. Of course, the gas supply means having the structure shown in Fig. 8 or other gas supply means is provided. Is also good.

Here, 501 and 502 are vacuum vessels, 50
Reference numerals 3 and 504 denote cathode electrodes for RF application and 505 and 506, respectively.
Is a gas introduction tube / heater; 507 and 508 are halogen lamps for heating the substrate; 509 and 510 are anode electrodes;
Reference numerals 1 and 512 are exhaust pipes.

Apparatus Examples 14 and 15 In this apparatus example, in the apparatus shown in the apparatus examples 1 and 2,
As a case where a relatively narrow band-shaped member is used, there is a case where a microwave applicator is provided only on one end surface of one side of a film forming chamber. In this case, however, a wire mesh for preventing microwave leakage, a punching board, a metal sheet, or the like is provided on the other end face.

Other Apparatus Examples For example, in the apparatus example 8, the isolation container 3 for forming a deposited film is used.
Apparatus in which microwave applicators of various shapes described above in 00, 300-a and 300-b are combined and mounted.

Further, the device shown in the device example 8 was used in two or three units.
Examples of the apparatus include a serially connected apparatus and an apparatus in which the above-described deposition film forming means using the RF plasma CVD method is mixed and connected.

Further, in the apparatus shown in the apparatus example 1 or 2, two or more pairs of microwave applicators are provided on both end faces of the film forming chamber to form a larger microwave plasma region, and the band-shaped member is formed. An apparatus that can form a relatively thick functional deposited film without changing the transport rate can be used.

An example of a semiconductor device suitably manufactured by the method and apparatus of the present invention is a solar cell. FIGS. 9 to 12 schematically show typical examples of the layer structure.

In the example shown in FIG. 9, a lower electrode 802, an n-type semiconductor layer 803, an i-type semiconductor layer 804,
p-type semiconductor layer 805, transparent electrode 806, and current collecting electrode 80
Reference numeral 7 denotes a photovoltaic element 800 deposited and formed in this order.
In this photovoltaic element, it is assumed that light is incident from the transparent electrode 806 side.

An example shown in FIG. 10 shows a light-transmitting support 801.
This is a photovoltaic element 800 'on which a transparent electrode 806, a p-type semiconductor layer 805, an i-type semiconductor layer 804, an n-type semiconductor layer 803, and a lower electrode 802 are formed in this order. In this photovoltaic element, it is assumed that light is incident from the light-transmitting support 801 side.

[0239] The example shown in FIG.
Alternatively, a p-type transistor using two types of semiconductor layers having different layer thicknesses as an i-layer
This is a so-called tandem-type photovoltaic element 813 formed by stacking two in-junction type photovoltaic elements 811 and 812. Reference numeral 801 denotes a support, which includes a lower electrode 802, an n-type semiconductor layer 803, an i-type semiconductor layer 804, and a p-type semiconductor layer 80.
5, an n-type semiconductor layer 808, an i-type semiconductor layer 809, a p-type semiconductor layer 810, a transparent electrode 806 and a current collecting electrode 807 are laminated in this order.
It is assumed that light is incident from the side 6.

In the example shown in FIG.
Alternatively, a p-type transistor using three types of semiconductor layers having different layer thicknesses as i-layers
This is a so-called triple-type photovoltaic element 824 formed by stacking three in-junction type photovoltaic elements 820, 821, and 823. Reference numeral 801 denotes a support, and the lower electrode 80
2, n-type semiconductor layer 803, i-type semiconductor layer 804, p-type semiconductor layer 805, n-type semiconductor layer 814, i-type semiconductor layer 81
5, a p-type semiconductor layer 816, an n-type semiconductor layer 817, an i-type semiconductor layer 818, a p-type semiconductor layer 819, a transparent electrode 806, and a current collecting electrode 807 are stacked in this order. It is assumed that light enters from the side of.

In each of the photovoltaic elements, n
The type semiconductor layer and the p-type semiconductor layer can be used by changing the lamination order of each layer according to the purpose.

Hereinafter, the configuration of these photovoltaic elements will be described.

The support 801 used in the present invention is preferably made of a material which is flexible and can form a curved shape, and may be a conductive material or an electrically insulating material. There may be. Further, they may be light-transmitting or non-light-transmitting, but are light-transmitting when light is incident from the support 801 side. It is necessary.

Specifically, the above-mentioned band-shaped member used in the present invention can be mentioned. By using the band-shaped member, the weight of the solar cell to be manufactured, the strength can be improved, and the transport space can be reduced.

Electrodes In the photovoltaic element of the present invention, appropriate electrodes are selectively used depending on the configuration of the element. Examples of these electrodes include a lower electrode, an upper electrode (transparent electrode), and a collecting electrode. (However, the upper electrode referred to here indicates the electrode provided on the light incident side, and the lower electrode indicates the electrode provided opposite to the upper electrode with the semiconductor layer interposed therebetween.) The electrodes are described in detail below. (I) Lower Electrode As the lower electrode 802 used in the present invention, the surface to which light for generating photovoltaic light is irradiated differs depending on whether or not the material of the support 801 is translucent (for example, In the case where the support 801 is a non-translucent material such as a metal, light for photovoltaic generation is irradiated from the transparent electrode 806 side as shown in FIG. 8A.) Location is different.

Specifically, in the case of the layer structure shown in FIGS. 9, 11 and 12, the support 801 and the n-type semiconductor layer 80 are formed.
3 is provided. However, when the support 801 is conductive, the support can also serve as the lower electrode. However, when the sheet resistance is high even if the support 801 is conductive, the electrode is used as a low-resistance electrode for extracting current or for the purpose of increasing the reflectivity on the support surface and effectively using incident light. 802 may be installed.

In the case of FIG. 10, a light-transmitting support 801 is used. Since light is incident from the support 801 side, the lower part is used for current extraction and light reflection at the electrode. An electrode 802 is provided to face the support 801 with the semiconductor layer interposed therebetween.

When an electrically insulating material is used as the support 801, a lower electrode 802 is provided between the support 801 and the n-type semiconductor layer 803 as an electrode for extracting current.
Is provided.

As the electrode material, Ag, Au, Pt, N
Metals such as i, Cr, Cu, Al, Ti, Zn, Mo and W or alloys thereof are listed, and thin films of these metals are formed by vacuum evaporation, electron beam evaporation, sputtering or the like. Also, care must be taken that the formed metal thin film does not become a resistance component with respect to the output of the photovoltaic element, and the sheet resistance is preferably 50Ω or less, more preferably 10Ω or less.

Although not shown in the figure, a diffusion preventing layer such as conductive zinc oxide may be provided between the lower electrode 802 and the n-type semiconductor layer 803. The effect of the diffusion preventing layer is not only to prevent the metal element forming the electrode 802 from diffusing into the n-type semiconductor layer, but also to provide a slight resistance value so as to sandwich the semiconductor layer. Lower electrode 80
To prevent short-circuiting caused by a defect such as a pinhole between the transparent electrode 806 and the transparent electrode 806, and to produce multiple interference by a thin film to confine incident light in a photovoltaic element. it can.

(Ii) Upper Electrode (Transparent Electrode) The transparent electrode 806 used in the present invention has a light transmittance of 85% or more in order to efficiently absorb light from the sun or white fluorescent light into the semiconductor layer. Desirably, the sheet resistance is desirably 100Ω or less so that the resistance of the output of the photovoltaic element does not become a resistance component. Materials having such characteristics include SnO, InO, ZnO, CdO, CdSnO, and ITO.
Metal oxides such as (InO + SnO), Au, Al,
A metal thin film in which a metal such as Cu is formed into a very thin and translucent shape is exemplified. The transparent electrode is laminated on the p-type semiconductor layer 805 in FIGS. 9, 11 and 12, and is laminated on the substrate 801 in FIG.
It is necessary to select ones with good adhesion to each other. As a manufacturing method thereof, a resistance heating evaporation method, an electron beam evaporation method, a sputtering method, a spray method, or the like can be used, and the method is appropriately selected as desired.

(Iii) Current collecting electrode The current collecting electrode 807 used in the present invention is a transparent electrode 806 for the purpose of reducing the surface resistance of the transparent electrode 806.
Provided above. Ag, Cr, Ni,
Examples thereof include thin films of metals such as Al, Ag, Au, Ti, Pt, Cu, Mo, W, and alloys thereof. These thin films can be stacked and used. The shape and area of the semiconductor layer are appropriately designed so that the amount of light incident on the semiconductor layer is sufficiently ensured.

For example, it is desirable that the shape is uniformly spread on the light receiving surface of the photovoltaic element, and that the area is preferably 15% or less, more preferably 10% or less with respect to the light receiving area.

The sheet resistance is desirably 50 Ω or less, more preferably 10 Ω or less.

I-Type Semiconductor Layer The semiconductor material constituting the i-type semiconductor layer suitably used in the photovoltaic device manufactured according to the present invention includes A-Si: H, A-Si: F, and A-Si: H: F,
A-SiC: H, A-SiC: F, A-SiC: H:
F, A-SiGe: H, A-SiGe: F, A-SiG
e: H: F, poly-Si: H, poly-Si:
In addition to so-called Group 4 and Group 4 alloy-based semiconductor materials such as F and poly-Si: H: F, so-called compound semiconductor materials of Groups 2-6 and 3-5 can be given.

Among them, A-SiGe: H and A-SiGe:
F, A-SiGe: H: F, A-SiC: H, AS
When a so-called Group 4 alloy semiconductor such as i: F or A-SiC: H: F is used for the i-type semiconductor layer, the bandgap (band gap: Eg) from the light incident side is appropriately changed. , Open circuit voltage (Voc), fill factor (FF: fill)
It is proposed that the factor be significantly improved. (20th IEEE PVSC, 1988, A
NOVEL DESIGN FOR AMORPHOU
S SILICON SOLARCELLS, S.I. Gu
ha. J. Yang et al. 13 to 16
Shows a specific example of the band gap profile. The mark → in the figure indicates the light incident side.

The band gap profile shown in FIG. 13 has a constant band gap from the light incident side. The band gap profile shown in FIG. 14 is of a type in which the band gap on the light incident side is narrow and the band gap gradually widens, and is effective in improving FF.
The band gap profile shown in FIG. 15 is of a type in which the band gap on the light incident side is wide and the band gap gradually narrows, and is effective in improving Voc.
The bandgap profile shown in FIG. 16 is of a type in which the bandgap on the light incident side is wide, the bandgap narrows relatively steeply, and expands again. By combining FIG. 14 and FIG. Can be obtained at the same time.

According to the method and apparatus of the present invention, for example, A
-Si: H (Eg ^opt = 1.72 eV) and A-SiG
FIG. 16 using e: H (Eg ^opt = 1.45 eV).
An i-type semiconductor layer having the band gap profile shown in FIG. A-SiC: H (Eg
^opt = 2.05 eV) and A-Si: H (Eg ^opt =
1.72 eV), an i-type semiconductor layer having a band gap profile shown in FIG. 15 can be manufactured.

The method and apparatus of the present invention are used in FIG.
A semiconductor layer having a doping profile shown in FIGS. The mark → in the figure indicates the light incident side.

FIG. 17 shows the profile of a non-doped i-type semiconductor layer. On the other hand, FIG. 18 shows a type in which the Fermi level on the light incident side is closer to the valence band and the Fermi level is gradually closer to the conduction band, which prevents recombination of photogenerated carriers and enhances the traveling properties of the carriers. It is effective. FIG. 19 shows a type in which the Fermi level gradually approaches the valence band from the light incident side. When an n-type semiconductor layer is provided on the light incident side, the same effect as in FIG. 18 is obtained. FIG. 20 shows a type in which the Fermi level changes from the valence band to the conduction band almost continuously from the light incident side.

Although these examples illustrate the case where the band gap is constant from the light incident side shown in FIG. 13, the Fermi level is similarly controlled in the case of the band gap profiles shown in FIGS. Can be.

By appropriately designing the band gap profile and the Fermi level porfile, a photovoltaic element having high photoelectric conversion efficiency can be manufactured. In particular, these profiles are shown in FIGS.
I of the tandem type or triple type photovoltaic element shown in FIG.
It is desirably applied to the type semiconductor layer.

P-type semiconductor layer and n-type semiconductor layer As the semiconductor material constituting the p-type or n-type semiconductor layer suitably used in the photovoltaic device manufactured by the present invention, the above-mentioned i-type semiconductor layer is used. Obtained by doping a valence electron controlling agent into a semiconductor material to be formed.

[Production Examples] Hereinafter, specific production examples using the microwave plasma CVD apparatus of the present invention will be described, but the present invention is not limited to these production examples.

Production Example 1 Using the continuous microwave plasma CVD apparatus shown in the apparatus example 7 in FIG. 3, continuous deposition of amorphous silicon germanium was performed.

First, a sufficiently degreased and cleaned SUS430BA is placed in a vacuum vessel 301 having a substrate sending-out mechanism.
Band-shaped substrate (45cm wide x 200m long x 0.25 thick)
mm), the substrate 101 is passed through the gas gate 321 and the transfer mechanism in the isolation container 300, and further through the gas gate 322 to the vacuum container 302 having the substrate take-up mechanism. The tension was adjusted to an extent that was not enough.

Therefore, each of the vacuum vessels 301 and 302 and the isolation vessel 300 is roughly evacuated by a rotary pump (not shown), and then a mechanical booster pump (not shown) is started to start the operation.
After evacuating to about 0 ^-3 Torr, an oil diffusion pump (Varian HS-32) (not shown) is used to further maintain the surface temperature of the belt-shaped member at 280 ° C. using the temperature control mechanisms 106a and 106b. It was evacuated to 5 × 10 ⁻⁶ Torr or less.

Note that the shape of the microwave applicator was
Table 7 shows conditions such as the curved shape, the arrangement of the gas introduction pipes, and the like. As the gas supply means, a gas supply means having three gas introduction pipes having the structure shown in FIG. 7A was used.

At the time when the degassing was sufficiently performed, the raw material gas for forming the deposited film was introduced from each gas introduction pipe under the conditions shown in Table 8, and the throttle valve attached to the oil diffusion pump was opened. By adjusting the degree, the pressure in the isolation container 300 was maintained at 8 mTorr. When the pressure was stabilized, microwaves having an effective power of 0.05 kW × 2 were emitted from the microwave power supply (not shown) of 2.45 GHz into the film forming chamber from the applicators 107 and 108. The raw material gas immediately introduced is turned into plasma to form a plasma region.
There was no leakage to the isolated container side from the interval of 03.
Also, microwave leakage was not detected.

Accordingly, the supporting / transporting rollers 102, 1
03 and the supporting / transporting rings 104 and 105 (both driving mechanisms are not shown) were started, and the transport speed of the substrate 101 was controlled to be 30 cm / min.

The gas gates 321 and 322 are supplied with H ₂ gas as gate gas through gate gas introduction pipes 316 and 317.
A gas is flowed at 50 sccm, and the gas is exhausted from the exhaust holes 318 and 318 by an oil diffusion pump (not shown).
orr was controlled.

For 30 minutes after the start of transport, a deposited film was formed continuously. In addition, since a long substrate is used, after the end of this manufacturing example, another deposited film is continuously formed, and after all the depositions are completed, the substrate is cooled and taken out.
The thickness distribution of the deposited film on the substrate formed in this manufacturing example was measured within 5% in the width direction and the longitudinal direction, and was found to be within 5%, and the deposition rate was 54 ° / sec on average.

Part of the substrate on which the deposited film is formed
Cut out, SIMS (IMES-3 manufactured by CAMECA)
When the composition analysis in the depth direction of the deposited film was performed using the method f), the depth profiles shown in FIG.
It was found that the band gap profile shown in FIG. 4 was formed. In addition, a hydrogen analyzer in metal (EMGA-
1100, manufactured by Horiba, Ltd.), the total hydrogen content in the film was determined to be 16 ± 2 atomic%.

Manufacturing Example 2 Following the deposited film forming step performed in Manufacturing Example 1,
After stopping the introduction of the used raw material gas and evacuating the internal pressure of the isolation container 300 to 5 × 10 Torr or less, a raw material gas for forming a deposited film is introduced from each gas introducing pipe under the conditions shown in Table 9, and the internal pressure is reduced. Deposited films were continuously formed under the same conditions except that the pressure was maintained at 9 mTorr, the microwave power was 0.55 kW × 2, and the transfer speed was 3 cm / min.

After the completion of this production example and other production examples, the substrate was cooled and taken out, and the film thickness distribution of the deposited film formed in this production example was measured in the width direction and the longitudinal direction. And the deposition rate averaged 62Å /
sec.

Part of the substrate on which the deposited film was formed
Cut out, SIMS (IMES-3 manufactured by CAMECA)
When the composition analysis in the depth direction of the deposited film was performed using f), the depth profiles shown in FIG.
It was found that the band gap profile shown in FIG. 6 was formed. In addition, a hydrogen analyzer in metal (EMGA-
1100, manufactured by Horiba, Ltd.), the total hydrogen content in the film was determined to be 17 ± 2 atomic%.

Manufacturing Example 3 Following the deposited film forming step performed in Manufacturing Example 1,
After stopping the introduction of the used raw material gas and evacuating the internal pressure of the isolation container 300 to 5 × 10 ⁻⁶ Torr or less, the raw material gas for forming a deposited film was introduced from each gas introducing pipe under the conditions shown in Table 10. , The internal pressure was maintained at 18 mTorr, the microwave power was 1.0 kW × 2, and the transport speed was 30 cm / m.
A deposited film was continuously formed under the same conditions except that “in” was set.

After completion of this production example and other production examples, the substrate was cooled and taken out, and the film thickness distribution of the deposited film formed in this production example was measured in the width direction and the longitudinal direction. And the deposition rate averaged 51Å /
sec.

Part of the substrate on which the deposited film was formed
Cut out, SIMS (IMES-3 manufactured by CAMECA)
When the composition analysis in the depth direction of the deposited film was performed using the method f), the depth profiles shown in FIG.
It was found that the band gap profile shown in FIG. 5 was formed. In addition, a hydrogen analyzer in metal (EMGA-
1100, manufactured by Horiba, Ltd.), the total hydrogen content in the film was determined to be 15 ± 2 atomic%.

Production Example 4 The internal pressure of the isolation vessel 300 was evacuated to 5 × 10 Torr or less in the same manner as in the deposited film formation step performed in Production Example 1, and then the deposited film was passed through each gas introduction pipe under the conditions shown in Table 11. A deposition film was formed under the same conditions except that a forming material gas was introduced, the internal pressure was maintained at 8 mTorr, the microwave power was 0.85 kW × 2, and the transfer speed was 60 cm / min.

In this production example, the gas supply means having the structure shown in FIG. 8 was used. Gas introduction pipe 703a
And 703b are arranged at 2 cm left and right from the center of the film forming chamber, and the stainless steel gas rectifying plate is arranged from the center of the space below the film forming chamber to 1 cm above the center of the film forming chamber.

After completion of this production example and other production examples, the substrate was cooled and taken out, and the film thickness distribution of the deposited film formed in this production example was measured in the width direction and the longitudinal direction. The deposition rate averages 122Å
/ Sec.

Part of the substrate on which the deposited film was formed
Cut out, SIMS (IMES-3 manufactured by CAMECA)
When the composition analysis in the depth direction of the deposited film was performed using f), the depth profiles shown in FIG.
It was found that the doping profile shown in FIG. 8 was formed. Also, a hydrogen analyzer in metal (EMGA-110)
0, manufactured by Horiba Seisakusho), and the total amount of hydrogen in the film was determined to be 19 ± 2 atomic%.

Production Example 5 In this production example, a pin type photovoltaic element having a layer structure shown in the schematic sectional view of FIG. 9 was produced using the apparatus shown in FIG.

The photovoltaic element comprises a substrate 801, a lower electrode 802, an n-type semiconductor layer 803, an i-type semiconductor layer 804 having a band gap profile shown in FIG. 16, a p-type semiconductor layer 805, a transparent electrode 806, and a collector. This is a photovoltaic element 800 in which the electrodes 807 are deposited in this order. In this photovoltaic element, it is assumed that light is incident from the transparent electrode 806 side, and the i-type semiconductor layer 80
The hand gap profile of No. 4 was as shown in FIG.

First, the same SUS as used in Production Example 1 was used.
Set the 430BA strip substrate in a continuous sputtering device,
1 using an Ag (99.99%) electrode as a target
000 ° Ag thin film and ZnO (99.9
99%) 1.2 μm Z using electrodes as targets
A lower electrode 802 was formed by sputtering a thin film of nO.

Subsequently, the strip-shaped substrate on which the lower electrode 802 was formed was set in the continuous deposition film forming apparatus shown in FIG. 4 in the same manner as in Production Example 1. At this time, the conditions such as the curved shape of the substrate in the isolation container 300 are set in the
It is shown in the table. Further, under the conditions shown in Table 13, a source gas for forming a deposited film was introduced from each gas introduction pipe.

In the isolation containers 300-a and 300-b, the n-type a-S
An i: H: F film and a p ⁺ type μc-Si: H: F film were formed.

First, microwave plasma is generated in each of the film forming chambers.
1 was transported from the left side to the right side in the drawing at a transport speed of 55 cm / min, and n, i, and p-type semiconductor layers were continuously formed.

After laminating a semiconductor layer over the entire length of the belt-like member 101, the semiconductor layer was taken out after cooling, and a 35 cm × 70 cm solar cell module was continuously produced by a continuous modularization apparatus.

With respect to the manufactured solar cell module,
When the characteristics were evaluated under M1.5 (100 mW / cm ² ) light irradiation, a photoelectric conversion efficiency of 7.6% or more was obtained, and the variation in characteristics between modules was within 5%.

Also, AM1.5 (100 mW / cm ² )
The rate of change of the photoelectric conversion efficiency from the initial value after 500 hours of continuous irradiation with light was measured and found to be within 9.5%.

By connecting these modules, a power supply system of 5 kW could be manufactured.

Manufacturing Example 6 In this manufacturing example, in the pin-type photovoltaic element manufactured in Manufacturing Example 5, a-SiGe: H:
15 shows an example in which an A-SiC: H: F film having a band gap profile shown in FIG. 15 is used instead of the F film.

For the A-SiC: H: F film, a raw material gas for forming a deposited film was introduced from each gas introduction pipe under the conditions shown in Table 15, and the surface temperature of the belt-shaped member was 270 ° C. and the internal pressure was 18 mT.
It was held at orr and the microwave power was formed as 1.2 kW × 2. Then, another semiconductor layer was formed and modularized by the same operation and method as in Production Example 5 except that the transfer speed was set to 50 cm / min, to produce a solar cell module.

With respect to the manufactured solar cell module,
When the characteristics were evaluated under M1.5 (100 mW / cm ² ) light irradiation, a photoelectric conversion efficiency of 6.9% or more was obtained, and the variation in characteristics between the modules was within 5%.

AM1.5 (100 mW / cm ² )
The rate of change of the photoelectric conversion efficiency from the initial value after 500 hours of continuous irradiation with light was measured and found to be within 9.5%.

By connecting these modules, a 5 kW power supply system could be manufactured.

Manufacturing Example 7 In this manufacturing example, in the pin-type photovoltaic element manufactured in Manufacturing Example 5, A-SiGe: H:
An example is shown in which an A-Si: H: F film having a Fermi level profile shown in FIG. 18 is used instead of the F film.

For the A-Si: H: F film, the raw material gas for forming the deposited film was introduced from each gas introduction pipe under the conditions shown in Table 16, and the surface temperature of the belt-shaped member was 270 ° C. and the internal pressure was 8 mTorr.
r, and the microwave power was formed at 0.65 kW × 2. Then, another semiconductor layer was formed and modularized by the same operation and method as in Production Example 5 except that the transfer speed was set to 50 cm / min, to produce a solar cell module.

Regarding the manufactured solar cell module,
When the characteristics were evaluated under M1.5 (100 mW / cm ² ) light irradiation, a photoelectric conversion efficiency of 8.6% or more was obtained, and the variation in characteristics between modules was within 5%.

Also, AM1.5 (100 mW / cm ² )
The rate of change of the photoelectric conversion efficiency from the initial value after 500 hours of continuous irradiation with light was measured and found to be within 9.5%.

By connecting these modules, a 5 kW power supply system could be manufactured.

Production Example 8 In this production example, a photovoltaic element having a layer structure shown in FIG. 11 was produced. In manufacturing, the isolation containers 300-a ', 300', and 300-b 'having the same configuration as the isolation containers 300-a, 300, and 300-b in the apparatus shown in FIG. 4 are further connected in this order via a gas gate. Device (not shown)
Was used.

The belt-shaped member was made of the same material and treated as used in Production Example 1, and the lower cell was produced in Production Example 5 and the upper cell was produced in the same manner as produced in Production Example 7. The semiconductor layer has a layer structure, and the manufacturing condition of each semiconductor layer is such that the surface temperature of the band member is 270 ° C.
Except that the temperature was set to ℃, 260 ℃, 250 ℃, 240 ℃, the same as in the case of each production example. The modularization process was performed in the same operation and method as in Production Example 5, to produce a solar cell module.

About the manufactured solar cell module, A
When the characteristics were evaluated under M1.5 (100 mW / cm) light irradiation, a photoelectric conversion efficiency of 10.5% or more was obtained, and the variation in the characteristics between the modules was within 5%.

Further, the rate of change of the photoelectric conversion efficiency from the initial value after continuous irradiation of AM1.5 (100 mW / cm) light for 500 hours was within 9%.

By connecting these modules, a 5 kW power supply system could be manufactured.

Production Example 9 In this production example, a photovoltaic element having a layer structure shown in FIG. 11 was produced. At the time of fabrication, the isolation containers 300-a ', 300', and 300-b 'having the same configuration as the isolation containers 300-a, 300, and 300-b in the apparatus shown in FIG. A connected device (not shown) was used.

[0310] The band-shaped member used was the same material and processed as used in Production Example 1, and the lower cell was the same as that produced in Production Example 6 and the upper cell was the same as that produced in Production Example 6. The manufacturing conditions of each semiconductor layer are as follows: the surface temperature of the band member is set to 260 ° C., 250 ° C., 25 ° C.
Except for 0 ° C., 240 ° C., 240 ° C., and 230 ° C., it was the same as in each of the production examples. Modularization process is Manufacturing Example 5
By performing the same operation and method as described above, a solar cell module was produced.

[0311] Regarding the manufactured solar cell module, A
When characteristics were evaluated under M1.5 (100 mW / cm ² ) light irradiation, a photoelectric conversion efficiency of 10.4% or more was obtained, and the variation in characteristics between modules was within 5%.

Further, the rate of change of the photoelectric conversion efficiency with respect to the initial value after continuous irradiation of AM1.5 (100 mW / cm) light for 500 hours was within 9%.

By connecting these modules, a 5 kW power supply system could be manufactured.

Production Example 10 In this production example, a photovoltaic element having a layer structure shown in FIG. 12 was produced. In manufacturing, the isolation containers 300-a ', 300', 300-b ', and 3 having the same configuration as the isolation containers 300-a, 300, and 300-b in the apparatus shown in FIG.
A device (not shown) in which 00-a ″, 300 ″, and 300-b ″ were further connected in this order via a gas gate was used.
The band-shaped member was made of the same material and treated as used in Production Example 1, and the lower cell was prepared in Production Example 5.
The intermediate cell has the same layer configuration as that of the production example 7 and the upper cell has the same layer constitution as that of the production example 6, and the conditions for producing the deposited film of each semiconductor layer are shown in Tables 17 and 18. The modularization process was performed in the same operation and method as in Production Example 5, to produce a solar cell module.

With respect to the manufactured solar cell module,
When characteristics were evaluated under M1.5 (100 mW / cm ² ) light irradiation, a photoelectric conversion efficiency of 10.7% or more was obtained, and a variation in characteristics between modules was within 5%.

Further, AM1.5 (100 mW / cm ² )
When the rate of change of the photoelectric conversion efficiency from the initial value after 500 hours of continuous irradiation with light was measured, it was within 8.5%.

By connecting these modules, a 3 kW power supply system could be manufactured.

[0318]

[Table 1]

[0319]

[Table 2]

[0320]

[Table 3]

[0321]

[Table 4]

[0322]

[Table 5]

[0323]

[Table 6]

[0324]

[Table 7]

[0325]

[Table 8]

[0326]

[Table 9]

[0327]

[Table 10]

[0328]

[Table 11]

[0329]

[Table 12]

[0330]

[Table 13]

[0331]

[Table 14]

[0332]

[Table 15]

[0333]

[Table 16]

[0334]

[Table 17]

[0335]

[Table 18]

[0336]

According to the method of the present invention, the belt-like member constituting the side wall of the film formation space is continuously moved, and two or more kinds of raw material gases having different compositions are formed in the film formation space. Are introduced separately via a plurality of gas supply means, respectively, in the width direction of the band-shaped member constituting the side wall of the film forming space,
By radiating microwave energy from microwave applicator means for radiating microwave energy in a direction parallel to the traveling direction of the microwave and confining the microwave plasma in the film forming space,
A large-area functional deposition film whose composition is controlled can be continuously formed with good reproducibility.

Further, a functional deposition film having an arbitrary band gap profile and a doping profile can be efficiently and continuously formed on a belt-like member which moves continuously by the method and the apparatus of the present invention.

The stability and reproducibility of the microwave plasma are improved by confining the microwave plasma in the film forming space by the method and apparatus of the present invention, and the utilization efficiency of the source gas for forming the deposited film is dramatically improved. Can be increased. Furthermore, by continuously transporting the belt-like member, the deposited film having an arbitrary composition distribution and film thickness can be uniformly distributed over a large area by continuously changing the shape, length, and transport speed of the curve. Can be deposited.

According to the method and apparatus of the present invention, it is possible to form a functional deposition film whose composition is controlled with good uniformity continuously on the surface of a relatively wide and long strip-shaped member. Therefore,
In particular, it can be suitably used as a mass-production machine for high-efficiency large-area solar cells.

Further, since the deposited film can be formed continuously without stopping the discharge, good interface characteristics can be obtained when manufacturing a laminated device or the like.

Further, it is possible to form a deposited film under a low pressure, to suppress the generation of polysilane powder, and to suppress the polymerization of active species, thereby reducing defects and
It is possible to improve the film characteristics and the stability of the film characteristics.

Therefore, the operation rate and the yield can be improved.
It becomes possible to mass produce inexpensive and highly efficient solar cells.

Further, the solar cell manufactured by the method and the apparatus of the present invention has a high photoelectric conversion efficiency and has little characteristic deterioration over a long period of time.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of a microwave plasma CVD apparatus of the present invention.

FIG. 2 is a schematic diagram of the microwave applicator means of the present invention.

FIG. 3 is an overall schematic view of an example of a continuous microwave plasma CVD apparatus according to the present invention.

FIG. 4 is an overall schematic view of an example of a continuous microwave plasma CVD apparatus according to the present invention.

FIG. 5 is an overall schematic view of one example of a continuous microwave plasma CVD apparatus of the present invention.

FIG. 6 is a schematic cross-sectional view for explaining a mounting angle of a rectangular waveguide according to the present invention.

FIG. 7 is a schematic side sectional view showing an arrangement of gas introduction pipes in the apparatus of the present invention.

FIG. 8 is a schematic side sectional view showing an arrangement of gas introduction pipes in the apparatus of the present invention.

FIG. 9 is a schematic cross-sectional view of a pin photovoltaic device manufactured in the present invention.

FIG. 10 is a schematic cross-sectional view of a pin photovoltaic device manufactured in the present invention.

FIG. 11 is a schematic cross-sectional view of a pin photovoltaic device manufactured in the present invention.

FIG. 12 is a schematic cross-sectional view of a pin photovoltaic element manufactured in the present invention.

FIG. 13 is a diagram for explaining a band gap profile of a deposited film formed according to the present invention.

FIG. 14 is a diagram for explaining a band gap profile of a deposited film formed according to the present invention.

FIG. 15 is a diagram for explaining a band gap profile of a deposited film formed according to the present invention.

FIG. 16 is a diagram for explaining a band gap profile of a deposited film formed according to the present invention.

FIG. 17 is a diagram illustrating a doping profile of a deposited film formed according to the present invention.

FIG. 18 is a diagram for explaining a doping profile of a deposited film formed according to the present invention.

FIG. 19 is a diagram for explaining a doping profile of a deposited film formed according to the present invention.

FIG. 20 is a diagram for explaining a doping profile of a deposited film formed according to the present invention.

FIG. 21 is a diagram showing a depth profile of a component element of a deposited film formed in a production example of the present invention.

FIG. 22 is a diagram showing a depth profile of a constituent element of a deposited film formed in a production example of the present invention.

FIG. 23 is a diagram showing a depth profile of a deposited film component element formed in a production example of the present invention.

FIG. 24 is a diagram showing a depth profile of a component element of a deposited film formed in a production example of the present invention.

FIG. 25 is a diagram schematically showing a pressure gradient of a gas gate means in the present invention.

FIG. 26 is a diagram schematically showing a pressure gradient of a gas gate means in the present invention.

[Explanation of symbols]

101 Belt-shaped member 102, 103 Transport roller 104, 105 Transport ring 106a-e Temperature control mechanism 107, 108 Microwave applicator 109, 110 Microwave transparent member 111, 112 Rectangular waveguide 113a, b, c, 703a, b Gas introduction pipe 114 Exhaust pipe 115a, b Isolation passage 116 Film deposition chamber 200 Microwave applicator 201, 202 Microwave transparent member 203a, b Microwave matching disk 204 Inner cylinder, 205 Outer cylinder 206 Fixing ring 207 Choke Flange 208 Rectangular waveguide 209 Cooling medium 210 O-ring 211 Groove 212 Metal seal 213, 214 Cooling air introduction / exhaust hole 301, 302, 501, 502 Vacuum container 303 Delivery bobbin 304 Winding bobbin 305, 306 Feed rollers 307, 308, 309 Throttle valves 310, 311, 318, 319, 320 Exhaust holes 312, 313 Temperature control mechanisms 314, 315 Pressure gauges 316, 317, 405, 406, 407, 408 Gate gas inlet pipes 321, 322, 401, 402, 403, 404 Gas gate 409, 410, 411, 412 Gate gas exhaust pipe 503, 504 Cathode electrode 505, 506 Gas introduction pipe 507, 508 Halogen lamp 509, 510 Anode electrode 511, 512 Exhaust hole 701a, b, c, 704a, b Gas outlet 702 Gas rectifier 801 Support 802 Lower electrode 803, 808, 814, 817 n-type semiconductor layer 804, 809, 815, 818 i-type semiconductor layer 800, 800 ', 811, 812, 820, 82 ,
823 pin junction type photovoltaic element 805, 810, 816, 819 p-type semiconductor layer 806 upper electrode 807 current collecting electrode 813 tandem type photovoltaic element 824 triple type photovoltaic element

──────────────────────────────────────────────────続 き Continuation of the front page (51) Int.Cl. ⁶ identification code FI H01L 31/04 H01L 31/04 V (58) Investigation field (Int.Cl. ⁶ , DB name) H01L 21/205 C23C 16 / 50 C23C 16/54 H01L 21/285 H01L 21/31 H01L 21/04

Claims (23)

(57) [Claims] 1. A column-shaped film-forming space having a side wall of the moving band-shaped member is formed in the middle of the band-shaped member while continuously moving the band-shaped member in a longitudinal direction, and at least two films having different compositions are formed in the film-forming space. A microwave in which at least one kind of raw material gas for forming a deposited film is separately introduced through a plurality of gas supply means, and at the same time, microwave energy is radiated in a direction parallel to a traveling direction of the microwave. From the applicator means, the microwave energy is radiated to generate microwave plasma in the film forming space, and the side wall exposed to the microwave plasma constitutes the side wall and continuously moves on the surface of the band-shaped member. Microwave plasma C characterized by forming a deposited film with controlled composition
A method of continuously forming a large-area functional deposition film by a VD method. 2. In the middle of the moving band-like member,
Using the bending start end forming means and the bending end end forming means,
2. The side wall of the film forming space according to claim 1, wherein the band-shaped member is curved by leaving a gap in a longitudinal direction of the band-shaped member between the curve start end forming unit and the curve end end forming unit. A method of continuously forming a large-area functional deposition film. 3. The method according to claim 1, wherein at least one or more of the microwave applicator means disposed on one or both sides of both end surfaces of the columnar film forming space formed with the band-shaped member as a side wall. The method for continuously forming a large-area functional deposition film according to claim 1, wherein wave energy is radiated into the deposition space. 4. The large area functional deposition film according to claim 3, wherein said microwave applicator means is disposed in a direction perpendicular to said end face to radiate said microwave energy in a direction parallel to said side wall. Method to form the target. 5. The microwave applicator means for radiating the microwave energy through a microwave permeable member provided at a tip portion of the microwave applicator means.
5. The method for continuously forming a large-area functional deposition film according to the above. 6. The large-area functional deposition film according to claim 5, wherein the microwave applicator means keeps the airtightness between the microwave applicator means and the film formation space. How to form. 7. The microwave applicator means,
4. The large-sized device according to claim 3, wherein, when the two microwave applicators are disposed so as to face each other, the microwave energy radiated from one microwave applicator is not received by the other microwave applicator. A method of continuously forming a functional deposited film having a large area. 8. The continuous formation of a large-area functional deposition film according to claim 1, wherein the microwave energy radiated into the columnar deposition space is prevented from leaking out of the deposition space. how to. 9. The gas supply means is disposed in parallel with the width direction of the band-like member constituting each of the side walls, and discharges the deposition film forming raw material gas in one direction toward the adjacent band-like member. The method of continuously forming a large-area functional deposition film according to claim 1, wherein 10. A gap left in the longitudinal direction of the band-shaped member between the curved start end forming means and the curved end end forming means, wherein a raw material gas for forming a deposited film introduced into the film forming space is introduced. The method for continuously forming a large-area functional deposition film according to claim 1, wherein the exhaust gas is further exhausted. 11. The method according to claim 1, wherein a conductive treatment is applied to at least one surface of the strip-shaped member. 12. An apparatus for continuously forming a functional deposition film on a continuously moving strip member by a microwave plasma CVD method, wherein said strip member is continuously moved in its longitudinal direction. Through a curved portion forming means for bending in the middle thereof, a column-shaped film forming chamber which is formed with the band-shaped member as a side wall and which can hold the inside thereof substantially in a vacuum, is provided in the film forming chamber. Microwave applicator means for emitting microwave energy in a direction parallel to the traveling direction of microwaves for generating microwave plasma, exhaust means for exhausting the film formation chamber, and The apparatus includes at least two or more gas supply means for introducing a deposition film forming source gas into the chamber, and temperature control means for heating and / or cooling the belt-shaped member. An apparatus for continuously forming a functionally-deposited film, wherein a deposition film having a controlled composition is formed on a surface of the continuously moving belt-like member exposed to the microwave plasma. 13. The bending portion forming means comprises at least one set of a bending start end forming means and a bending end end forming means, and the bending start end forming means and the bending end end forming means, The apparatus for continuously forming a functional deposition film according to claim 12, wherein the apparatus is disposed with a gap left in the longitudinal direction of the band-shaped member. 14. The curved portion forming means includes at least a pair of supporting / transporting rollers and a supporting / transporting ring, wherein the pair of supporting / transporting rollers leave a gap in a longitudinal direction of the band-shaped member. 14. The continuous functional deposition film forming apparatus according to claim 13, wherein the functional deposition film is arranged in parallel. 15. The function according to claim 12, wherein at least one or more of said microwave applicator means is provided on one or both sides of both end faces of a columnar film forming chamber formed with said strip-shaped member as a side wall. Continuous forming device for conductive deposited film. 16. The apparatus for continuously forming a functional deposition film according to claim 15, wherein the microwave applicator is disposed in a direction perpendicular to the end face. 17. At the tip of the microwave applicator, the film forming chamber and the microwave applicator are air-tightly separated, and the microwave energy radiated from the microwave applicator is used for the film formation. The apparatus for continuously forming a functional deposited film according to claim 12, further comprising a microwave transmitting member that transmits the signal to a room. 18. The apparatus for continuously forming a functional deposition film according to claim 12, wherein at least one surface of the belt-shaped member is subjected to a conductive treatment. 19. The apparatus according to claim 15, wherein the microwave energy is transmitted to the microwave applicator means via a rectangular and / or elliptical waveguide. 20. When the microwave applicator means is disposed opposite to each other at both end surfaces of the film forming chamber, the length of the rectangular and / or elliptical waveguide connected to the microwave applicator means is increased. 20. A plane including sides, a plane including a long axis, or a plane including a long side and a plane including a long axis are arranged so as not to be parallel to each other.
The continuous formation apparatus of a functional deposition film according to 1. 21. An angle formed between a plane including a long side and / or a plane including a long axis of the rectangular and / or elliptical waveguide and a plane including a center axis of the pair of supporting and conveying rollers is not perpendicular. 21. The continuous functional deposition film forming apparatus according to claim 20, wherein 22. The apparatus for continuously forming a functional deposition film according to claim 12, wherein the gas supply means is disposed in parallel with a width direction of the belt-shaped member constituting the side wall. 23. The apparatus for continuously forming a functional deposition film according to claim 22, wherein the gas supply means is provided with a gas discharge hole directed to a belt-shaped member constituting the adjacent side wall.