JP2722114B2 - Method and apparatus for continuously forming large-area functional deposition film by microwave plasma CVD - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention is to generate uniform microwave plasma over a large area, and to decompose and excite raw material gas by a plasma reaction caused by the microwave plasma. The present invention relates to a method and an apparatus for continuously forming a large-area functional deposition film by using the method.

More specifically, there is provided a method and apparatus capable of dramatically increasing the utilization efficiency of the raw material gas and capable of continuously forming a functional deposition film having high uniformity at high speed over a large area. Can realize mass production of large-area thin-film semiconductor devices such as photovoltaic elements at low cost.

[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.

However, it is expected as a power generation method to replace thermal power generation,
In nuclear power, which has already entered the practical period,
Serious radioactive contamination, which is typified by the Chernobyl nuclear power plant accident, harms the human body and invades the natural environment, threatening the future spread of nuclear power generation. There are even countries that have banned laws.

In addition, the use of fossil fuels, such as coal and petroleum, is steadily increasing in order to meet the increasing demand for electricity even with thermal power generation. It raises the concentration of greenhouse gases such as carbon dioxide and causes global warming, and the annual average temperature of the earth is steadily rising.
The Energy Agency) has proposed reducing CO2 emissions by 20% by 2005.

Against this background, the artificial increase in developing countries and the accompanying increase in electricity demand are inevitable.
The power supply issue has to be considered on a global scale, coupled with the increase in power consumption per capita due to the further promotion of electronics in lifestyles in advanced countries.

Under such circumstances, the power generation method using solar cells using sunlight does not cause the above-mentioned problems such as radioactive contamination and global warming, and the sunlight falls all over 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, so that it can respond to future increases in power demand without causing environmental destruction. Attention has been paid to a clean power generation system, and various research and developments have been made for practical use.

By the way, for a power generation method using a solar cell, in order to establish it as one that meets the power demand, the solar cell to be used has sufficiently high photoelectric conversion efficiency and excellent characteristic stability, and It is basically required to be mass-produced.

By the way, in order to supply necessary electricity in a general household,
Where a solar cell with an output of about 3 kW per household is required, if the photoelectric conversion efficiency of the solar cell is, for example, about 10%, the area of the solar cell for obtaining the required output is about 30 m ² Becomes For example, in order to supply necessary power in a home of 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 is decomposed by glow discharge to deposit 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 such a method are attracting attention because of their high mass productivity and the possibility that they can be manufactured at a lower cost than solar cells manufactured using single-crystal silicon or the like. Has been made.

In a power generation system using a solar cell, a form in which unit modules are connected in series or in parallel to obtain a desired current and voltage by unitization is often adopted, and disconnection or short circuit does not occur in each module. Is required. 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, be ensured 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, Required to achieve significant reductions in production costs.

As for the solar cell, a semiconductor layer, which is an important component, has a semiconductor junction such as a so-called pn junction or a 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.

Looking at this point, solar cells using thin-film semiconductors such as amorphous silicon, which have attracted attention,
In the production, a source gas containing an element serving as a dopant such as phosphine (PH ₃ ) or diborane (B ₂ H ₆ ) is mixed with silane or the like as a main source gas and glow discharge decomposition is performed to obtain a desired conductive type. A semiconductor film having
It is known that semiconductor bonding can be easily achieved by sequentially laminating these semiconductor films on a desired substrate. For this reason, in order to manufacture an amorphous silicon-based solar cell, a method has been proposed in which an independent film formation chamber for forming each semiconductor layer is provided, and each semiconductor layer is formed in the film formation chamber. ing.

For example, US Pat. No. 4,400,409 discloses a continuous plasma CVD apparatus employing a roll-to-roll method. According to this device,
A plurality of glow discharge regions are provided, and a sufficiently long flexible substrate having a desired width is arranged along a path in which the substrate sequentially passes through each of the glow discharge regions, and is required in each of the glow discharge regions. While depositing and forming a conductive type semiconductor layer,
It is stated that by continuously transporting the substrate in the longitudinal direction, an element having a semiconductor junction can be continuously formed. In this specification, a gas gate is used to prevent a dopant gas used for forming each semiconductor layer from being diffused or mixed into another glow discharge region. Specifically, the respective glow discharge regions each other, separated from each other by a slit-shaped separation passageway, and further the separation passage, for example, Ar, means adopted for forming the flow of exhaust gas such as H ₂ . From this, it can be said that this roll-to-roll system is suitable for mass production of semiconductor devices.

However, since the formation of each semiconductor layer is performed by a plasma CVD method using RF (radio frequency), it is naturally a limit to improve the film deposition rate while maintaining the characteristics of a continuously formed film. There is. 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 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.

In addition, Japanese Patent Application Laid-Open No. 61-288074 discloses a deposited film forming apparatus using an improved roll-to-roll method. 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 device 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 the thermal energy must be reduced. Although it is necessary to increase the supply amount, there is also a limit to a method for supplying a large amount of heat energy uniformly, and a method for generating a large amount of highly reactive active species and introducing it to the reaction space without loss.

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

For example, U.S. Pat.Nos. 4,517,223 and 4,50
No. 4,518 discloses a method of depositing and forming a thin film on a substrate having a small area in a microwave glow discharge plasma under a low pressure. Not only can high-quality deposited films be prevented by preventing the polymerization of active species that cause a decrease in film characteristics, but also the generation of powders such as polysilane in plasma can be suppressed.
Although it is said that the deposition rate can be dramatically improved, no specific disclosure has been made in forming a uniform deposited film over a large area.

On the other hand, U.S. Pat.No. 4,729,341 discloses a low-pressure microwave plasma CVD for depositing and forming a photoconductive semiconductor thin film on a large-sized cylindrical substrate by a high-power process using a pair of radiation-type waveguide applicators. Although a method and an apparatus are disclosed, the large-area substrate is limited to a cylindrical substrate, that is, a drum as a photoreceptor for electrophotography, and is applied to a large-area and long substrate. Absent.

In addition, the manufacturing process of the deposited film is a batch type, and the amount of the deposited film formed in a single preparation is limited, and the method relates to a method of continuously forming a large amount of the deposited film on a large-area substrate. No disclosure.

By the way, since plasma using microwaves has a short microwave wavelength, energy non-uniformity is likely to occur, and there are various problems that must be solved for increasing the area.

For example, an effective means for equalizing microwave energy is to use a slow-wave circuit, which has an abrupt increase in the microwave coupling to the plasma as the lateral distance of the microwave applicator increases. It has a unique problem that a significant reduction 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 to make the energy density near the surface of the substrate uniform has been attempted. For example, U.S. Pat.
No. 3 and 4,521,717 disclose 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.

Some proposals have been made to maintain plasma uniformity (ie, energy uniformity). The proposals are, for example, from the Journal of Vacuum Technology.
Science Technology) B-4 (January-February 1986) 295
Page-298 and B-4 of the magazine (January-February 1986) 126
See page-130. According to these reports, microwave plasma disk sources (MP
A microwave reactor called DS) has been proposed.
That is, the plasma has a disk-like or tablet-like shape, and its diameter is a function of the microwave frequency. And those reports disclose the following contents. That is, first, the plasma disk source can be changed by the microwave frequency. However, in the microwave plasma disc source which is designed to operate at 2.45 GHz, the plasma confinement diameter is at most about 10 cm, a most 118cm ³ about even if the plasma volume, the large area I can't say at all. The report also states that
In systems designed to operate at frequencies as low as 5 MHz, the lower frequency provides a plasma diameter of about 40 cm and a plasma volume of 2000 cm ³ . The report further reports that the lower frequency, e.g., 400 MHz
It is said that the discharge can be expanded to a diameter of more than 1 m by operating at. However, a device which achieves this content requires a very expensive specific device.

In other words, a large-area plasma can be achieved by lowering the frequency of the microwave, but a high-power microwave power supply in such a frequency range has not been generalized and is difficult to obtain. Very 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 using microwaves, a method of arranging an electromagnet around a cavity resonator and satisfying ECR (Electron Cyclotron Resonance) conditions is disclosed in Japanese Patent Laid-Open No. 55-141729. Japanese Patent Application Laid-Open No. 57-133636 and Japanese Patent Application Laid-Open No. 57-133636, and various reports have been made by academic societies and the like that various types of semiconductor thin films are formed using this high-density plasma. Microwave EC
R plasma CVD equipment has been commercialized.

However, in these methods using ECR, since a magnet is used to control the plasma, the non-uniformity of the plasma due to the wavelength of the microwave and the non-uniformity of the magnetic field distribution are also added. It is technically difficult to form a uniform deposited film on a substrate having a large area. In addition, when the device is enlarged for the purpose of increasing the area, the electromagnets naturally used also increase in size, resulting in an increase in weight and space,
Further, there are various problems that must be solved for practical use, such as measures against heat generation and the necessity of a DC stabilized power supply with a large current.

Furthermore, the characteristics of the deposited film formed are not at a level that can be said to be equivalent to those formed by the conventional RF plasma CVD method, and the deposited film is formed in a space where ECR conditions are satisfied. The characteristics and the deposition rate are extremely different between a deposited film formed in a so-called divergent magnetic field space outside the ECR condition and a deposited film formed outside the ECR condition. Therefore, this method is particularly suitable for the fabrication of semiconductor devices requiring high quality and uniformity. It can not be said.

The aforementioned U.S. Pat.Nos. 4,517,223 and 4,729,3
In the specification of No. 41, regarding obtaining a high density plasma,
It is disclosed that there is a need to maintain a very low pressure. 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, early provision of a novel microwave plasma process that solves the various problems of the above-described microwave means is desired.

By the way, thin-film semiconductors are used not only for solar cells as described above, but also for thin-film transistors (TFTs) for driving pixels of liquid crystal displays, which have large areas or long lengths such as photoelectric conversion elements and switching elements for contact image sensors. It is also suitably used for the production of thin film semiconductor devices that need to be used, and is partially used as a key component for the image input / output device. By providing a deposited film formation method,
It is expected that it will become more widely spread.

[Object of the invention]

The present invention overcomes the above-mentioned problems in the conventional thin film semiconductor device forming method and apparatus and provides a novel method and apparatus for forming a functional deposition film uniformly and at high speed over a large area. The purpose is to do so.

Another object of the present invention is to provide a method and an apparatus for continuously forming a functional deposition film on a belt-shaped member.

A further object of the present invention is to provide a method and 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.

Still 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 and apparatus for forming a photovoltaic device having a high efficiency and a high photoelectric conversion efficiency continuously on a relatively wide and long substrate. Is what you do.

[Structure and effect of the invention]

The present inventors have solved the above-mentioned problems in the conventional thin film semiconductor device forming apparatus and have conducted intensive studies to achieve the object of the present invention. Through a support / transport ring for forming a roller curved portion, and a support / transport roller for forming a curved end end, the support / transport roller is curved leaving a gap between the rollers, and the belt-shaped member is bent. A column-shaped film forming chamber as a side wall is formed, and microwave applicator means for emitting microwave energy in a direction parallel to a traveling direction of the microwave are opposed to both end faces of the film forming chamber. A pair is disposed, and a source gas for forming a deposited film is further introduced into the film forming chamber, and the pressure in the film forming chamber is reduced by exhausting gas from a gap left between the pair of supporting / transporting rollers. Under specified vacuum Holding and radiating the microwave energy from the microwave applicator means substantially parallel to the front wall, it was found that microwave plasma could 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-described findings, and continuously forms a large-area functional deposited film by a microwave plasma CVD method having the following points. Methods and apparatus.

The method of the present invention is as follows. That is, while continuously moving the band-shaped member in the longitudinal direction, a column-shaped film-forming space having the moving band-shaped member as a side wall is formed in the middle thereof, and the deposited film is formed in the film-forming space via a gas supply means. The raw material gas for formation is introduced, and at the same time, the microwave energy is radiated from the microwave applicator means for radiating the microwave energy in a direction parallel to the traveling direction of the microwave to radiate the microwave plasma, The microwave plasma CVD method is characterized in that it is generated in a film forming space, and forms a deposited film on the surface of the continuously moving strip-shaped member constituting the side wall exposed to the microwave plasma. This is a method of continuously forming a functional deposition film having a large area.

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

And it is arrange | positioned at one side or both sides among the both end surfaces of the pillar-shaped film-forming space formed with the said strip | belt-shaped member as a side wall.
The microwave energy is radiated into the deposition space via at least one or more of the microwave applicator means.

Also, 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 airtightness between the microwave applicator means and the film forming space is maintained by the microwave permeable member.

Further, in the case where the microwave applicator means is disposed so as to face each other at the both end surfaces, the microwave energy radiated from one microwave applicator means is not received by the other microwave applicator means. Deploy.

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

Further, the source gas for forming a deposited film introduced into the film forming space is exhausted from 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. To do.

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 continuously formed in the longitudinal direction. While moving, via a curved portion forming means for bending in the middle, the band-shaped member is formed as a side wall, and has a columnar film-forming chamber capable of holding the inside thereof substantially in a vacuum, Microwave applicator means for emitting microwave energy in a direction parallel to the traveling direction of the microwave for generating microwave plasma in the film formation chamber, and exhaust means for exhausting the film formation chamber Means for introducing a source gas for forming a deposited film into the film forming chamber, and temperature control means for heating and / or cooling the strip-shaped member, wherein the microphone of the strip-shaped member is provided. An apparatus for continuously forming a functional deposited film, wherein a deposited film is continuously formed on a surface exposed to microwave plasma.

In the apparatus of the present invention, the bending portion forming means includes at least one or more sets of a bending start end forming means and a bending end end forming means, wherein the bending start end forming means and the bending end end forming means are provided. The belt-shaped member is disposed with a gap left in the longitudinal direction.

The curved portion forming means is constituted by at least a pair of support / transport rollers and a support / transport ring,
The pair of support / transport rollers are disposed in parallel with a gap left in the longitudinal direction of the belt-shaped member.

In the apparatus of the present invention, on one or both sides of both end surfaces of a columnar film forming chamber formed with the band-shaped member as a side wall,
At least one or more of said microwave applicator means are provided.

And, the microwave applicator means is disposed in a direction perpendicular to the end face.

In the apparatus of the present invention, the film forming chamber and the microwave applicator are air-tightly separated from each other at the tip of the microwave applicator, and the microwave energy radiated from the microwave applicator is supplied to the microwave applicator. A microwave permeable member that allows transmission into the membrane chamber is provided.

In the device 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.

When the microwave applicator means is disposed to face each other on both end surfaces of the film forming chamber,
The planes including the long sides of the rectangular and / or elliptical waveguides connected to the microwave applicator means, the planes including the long axis, or the planes including the long side and the planes including the long axis are parallel to each other. It is arranged not to become.

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 to each other. Is established.

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

[Experiment]

Various experiments were performed on the generation conditions of microplasma for uniformly forming a functional deposition film on a belt-shaped member using the apparatus of the present invention, and will be described in detail 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 by the procedure described in Production Example 1 to be described later. We investigated the stability of microwave plasma and the degree of leakage of microwave to the outside of the deposition chamber.

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

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. The rectangular waveguide 111 is provided on the front side in the drawing, and the rectangular waveguide 112 is provided on the back side. O is the center of the curved shape and A-
A 'represents a plane including the central axis of the supporting / transporting rollers 102 and 103, and a plane perpendicular to this is designated as HH'. A plane B- parallel to the plane including the long side of the rectangular waveguide 111
The angle between B ′ 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 mounting angle of the rectangular waveguide 112. Here, the mounting angles θ ₁ , θ of the rectangular waveguides 111, 112
₂ if each exceeds 180 °, H if 180 ° or less
−H ′, the arrangement is 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 also equivalent.

In the present invention, the distance between the curved ends of the belt-shaped member defined by the support / transport rollers 102 and 103 is defined as a gap L.

Under the microwave plasma discharge conditions shown in Table 1, the second
Experiments and evaluations were performed on the stability and the like of microwave plasma under various combinations of θ ₁ and θ ₂ shown in the table.

Note that the microwave leakage is measured using the support / transport roller 10
A microwave detector was installed at a location about 5 cm away from the gap of 2,103, and the evaluation was performed.

 The evaluation results were 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 formation chamber were greatly changed. Specifically, θ ₁
And / or when θ ₂ is 0 °, the microwave leakage is the largest and the discharge state is unstable. At about 15 °, the microwave leakage is small but the discharge state is unstable. It is. At 30 ° or more, the leakage of the milo wave disappeared 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 in parallel to each other, the oscillation does not depend on the amount of microwave leakage. Power supply noise due to abnormalities increases, and discharge becomes unstable. In this discharge experiment, the case where the band-shaped member 101 was stationary and 1.2 m / min
, And no particular difference was observed in the discharge stability between the two.

Further, among the microwave plasma discharge conditions, the type and flow rate of the raw material gas, the microwave power, the inner diameter of the curved shape,
Even when the pressure in the film forming chamber was changed variously, there was no particular difference in the amount of microwave leakage and discharge stability caused by the arrangement of the rectangular waveguide.

EXPERIMENTAL EXAMPLE 2 In this experimental example, the apparatus shown in FIG. 6 was used and the supporting / transporting rollers shown in FIG.
The effect of changing the gap L between 102 and 103 on microwave plasma stability and film thickness distribution was 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.
The temperature control mechanisms 106a to 106e are operated so that the surface temperature of the belt-shaped member 101 becomes 250 ° C.
cm / min.

Table 3 shows the results of evaluating 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 band-shaped member and at 20 cm in the longitudinal direction, and the distribution was evaluated.

From these results, the capacity adjustment of the exhaust pump was not performed, and the pressure inside 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 width direction of the belt-shaped member. Was found to change significantly. Experimental Example 1
It was also found that microwave leakage also occurred when the gap L was too large even if the arrangement was such that microwave leakage did not occur. The reason why the microwave leakage from the gap L is reduced is that the dimension of the gap L is preferably equal to or less than 1/2 wavelength of the microwave wavelength, more preferably 1/4 wavelength.
It was when the wavelength was not more than the 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. 4, which had a high deposition rate and a good film thickness distribution among the prepared samples, had a deposition rate of about 100 mm / sec.
The source gas utilization efficiency calculated from the amount of the film deposited on the belt-shaped member is 55% of the total flow rate of the source gas used.
%Met.

Further, in the microwave plasma discharge conditions, when the microwave power, the inner diameter of the curve formation, and the like are variously changed, the film thickness distribution and the discharge stability are slightly changed, but are caused by the size of the gap L. Could not be a solution to the essential problem of

Experimental Example 3 In this experimental example, as in Experimental Example 1, the apparatus shown in Apparatus Example 2 was used, and the stability and the film thickness distribution of the microwave plasma when the inner diameter of the formed curved shape was changed. Was examined. For the inner diameter of the curved shape
Except for various changes in the range shown in the table, the 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 °.
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 set to 35 cm / min.

Table 4 shows the results of evaluating 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 band-shaped member and at 20 cm in the longitudinal direction, and the distribution was evaluated.

From these results, by changing the inner diameter of the curved shape without changing other discharge conditions, the discharge state changes, and the film thickness distribution of the deposited film formed changes remarkably, especially in the width direction of the band-shaped member. I found out. 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, it was found that, even when the microwave power, the pressure in the film forming chamber, and the like among the microwave plasma discharge conditions were variously changed, the film thickness distribution and the discharge stability were affected by the respective parameter changes. .

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 microwave when the source gas flow rate and the microwave power were variously changed. The stability of 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 are both arranged at 60 ° and 60 °.

Table 5 shows the results of evaluating 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 any case, when the microwave power is reduced, the pressure in the film formation chamber is reduced, or the flow rate of H ₂ as the source gas is increased, the discharge becomes unstable or almost no longer occurs. Indicates the limit value. Therefore, conversely, the microwave power, the pressure in the film forming chamber, or the SiH ₄
It has been found that the discharge becomes more stable when the flow rate is increased. In addition, in this discharge experiment, when the belt-shaped member 101 was stopped and when the belt-shaped member 101 was transported at a transport speed of 1.2 m / min, there was no particular difference in discharge stability between the two.

EXPERIMENTAL EXAMPLE 5 In this experimental example, similarly to Experimental Example 1, using the apparatus shown in Apparatus Example 2 and changing the width dimension of the band-shaped member, the effect on the stability and film thickness distribution of the microwave plasma, and the like. Was examined.

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 were the same as those shown in Table 1, and the type of rectangular waveguide was changed to EIAJ, WRI-32.
The mounting angles θ ₁ and θ ₂ were both set to 60 ° and 60 °. The surface temperature of the belt-like member was 25
The temperature was set to 0 ° C., and the transfer speed was set to 50 cm / min.

In addition, the microwave applicator was provided only on one side for samples Nos. 15 to 17, and a pair of microwave applicators was provided facing each other for samples Nos. 18 to 21.

Table 6 shows the results of evaluating 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 dimension of the belt-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.

Further, among the microwave plasma discharge conditions, when the type and flow rate of the source gas, the microwave power, the film forming chamber pressure, and the like are variously changed, the stability of the microwave plasma and the film thickness distribution are changed by each parameter change. It turned out to be affected.

Summary of Experimental Results In the method and apparatus of the present invention, the stability and uniformity of the microwave plasma are determined, for example, by the shape of the microwave applicator and the type and arrangement of the waveguide connected thereto,
Since various parameters such as the pressure in the deposition chamber during deposition, microwave power, degree of confinement of microwave plasma, volume and shape of discharge space are maintained intricately, only a single parameter can be used. Although it is difficult to find the optimum condition, the following tendency and condition range were found from the results of this experiment.

Regarding the pressure of the film forming chamber, preferably, 1.5 mTorr to 10
It was found that the pressure was 0 mTorr, more preferably 3 mTorr to 50 mTorr. With respect to microwave power, preferably 250
× 2W to 3000 × 2W, more preferably 300 × 2W to 1000 × 2
It turned out to be W. Regarding the inner diameter of the curved shape,
It has been found that it 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.

In addition, it is understood that when the amount of microwave leakage from the microwave plasma region increases, the stability of the microwave plasma is lacking, and the gap L between the curved ends of the belt-shaped member is preferably equal to or less than 1/2 wavelength of the microwave. It has been found that it is desirable to set the wavelength to preferably 1/4 wavelength or less.

Hereinafter, the method of the present invention will be described in more detail based on the facts found by the aforementioned [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.

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

When the width of the band-shaped member is relatively narrow, uniformity of the microwave plasma generated in the film forming space is maintained even by radiating the microwave energy from one side, but the width of the band-shaped member is For example, one of the microwave wavelengths
In the case of exceeding the wavelength, it is preferable to emit 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, and the columnar film formation space is similar to a so-called waveguide. It is desirable to have a structure. 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, as the formation of both end surfaces of the 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, It is preferable that the microwave energy radiated into the film forming space is transmitted to the film forming space almost uniformly, and the shape is circular, elliptical, square,
It is desirable that the shape be similar to a polygonal shape, be substantially symmetrical, and have a relatively smooth curved shape. Of course, the end face shape may be discontinuous 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.

Furthermore, in the method of the present invention, while efficiently transmitting microwave energy in the film forming space,
In order to stably generate, maintain and control the microwave plasma, it is desirable that the microwave transmission mode in the microwave applicator means is a single mode. Specifically, TE ₁₀ mode, TE ₁₁ mode, eH ₁ mode, TM ₁₁ mode, there may be mentioned a TM ₀₁ mode or the like, preferably TE ₁₀ mode, TE ₁₁ mode, eH ₁ mode is used. These transmission modes may be used alone or in combination. Further, microwave energy is transmitted to the microwave applicator means via a waveguide capable of transmitting the above-mentioned transmission mode. Furthermore,
The microwave energy is radiated into the film-forming space via an airtight microwave permeable member provided at a distal end portion of the microwave applicator means.

In the method 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 space, and the raw material gas is exhausted from the gap, and Is maintained at a predetermined reduced pressure state,
The dimensions of the gap require special consideration so that sufficient exhaust conductance is obtained and that microwave energy radiated into the film formation space does not leak out of the film formation space.

Specifically, the direction of the electric field of the microwave traveling in the microwave applicator means, the central axis of the support / transport roller as the bending start end forming means, and the support / transport roller as the bending end end forming means The microwave applicator means is arranged so that the planes including the central axis of the microwave applicator are 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.

Furthermore, the maximum dimension of the opening width in the longitudinal direction of the band-shaped member of the gap left between the bending start end forming means and the bending end end forming means is preferably 1/2 wavelength or less of the microwave wavelength, More preferably, it is desirable to set the wavelength to 1/4 wavelength or less.

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 received by the other microwave applicator means. The received microwave energy reaches the microwave power supply connected to the other microwave applicator means, thereby damaging the microwave power supply or causing an abnormality in microwave oscillation. Special care must be taken to prevent 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 radiated from only one of both end faces of the film forming space, it is necessary to prevent leakage of microwave energy from the other end face, The end face may be sealed with a conductive member, or a wire mesh whose hole diameter is preferably 1/2 wavelength or less, more preferably / 4 wavelength or less, of the wavelength of the microwave used,
It is desirable to cover with a punching board or the like.

In the method of the present invention, the microwave energy radiated into the film formation space has a strong correlation with the pressure in the film formation space, though it depends on the type of the source gas introduced into the film formation space. However, it tends to decrease significantly as the distance from the microwave permeable member provided in the microwave applicator increases. 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.

In the method of the present invention, the microwave applicator means has a traveling direction of radiated microwave energy,
It is desirable to arrange the film-forming space perpendicular to the end face of the film-forming space so as to be substantially parallel to the side wall of the film-forming space formed by the strip-shaped member. It is desirable that the microwave applicator is disposed at a position substantially equidistant from the side wall, but the position at which the microwave applicator is disposed is particularly limited when the curved shape of the side wall is asymmetric. There is no. 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 belt-shaped member, the stability of the microwave plasma generated therein, it is preferable that a constant shape is always maintained in order to maintain uniformity, It is desirable that the belt-shaped member is supported by the bending start end forming means and the bending end end forming means so as not to cause wrinkles, slack, lateral displacement and the like. And
In addition to the bending start end forming means and the bending end end forming means, a support means for maintaining 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.

It is desirable to use a flexible member capable of continuously forming the curved shape as the band-shaped member, and to form a smooth shape at the curved start end, the curved end end, and the middle curved portion.

The source gas for forming a deposited film introduced into the film forming space by the gas supply means is efficiently exhausted to the outside of the film forming space, and the inside of the space is set to a pressure at which the microwave plasma is uniformly generated. To be kept.

In order to uniformly and stably generate and maintain the microwave plasma in the columnar deposition space, the shape and volume of the deposition space, the type and flow rate of the source gas introduced into the deposition space, Although there are optimal conditions for the pressure in the film formation space, the amount of microwave energy radiated into the film formation space, and the matching of microwaves, etc., these parameters are organically connected to each other. However, it is desirable to set preferable conditions as appropriate.

That is, according to the method of the present invention, a film-forming space having a 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 of the film-forming space is formed. Microwave applicator means are arranged so that microwave energy can be radiated almost uniformly in the width direction of the band-shaped member constituting the side wall, and the conditions for generating and maintaining microwave plasma are adjusted and optimized, so that a large area can be obtained. 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 deposition space is formed in a columnar shape, and the sidewall thereof continuously moves, but also functions as a structural material, and
This is to serve also as a substrate or a support for forming a deposited film.

Here, the function as a structural material is a function of physically and chemically isolating an atmosphere space for film formation, that is, a film formation space and an atmosphere space not involved in film formation. For example, to form an atmosphere having a different gas composition and its state, to restrict the flow direction of the gas,
This means a function of forming atmospheres with different pressure differences.

That is, in the method of the present invention, the band-shaped member is curved to form the side wall of the columnar film-forming space, and the other remaining wall surfaces, that is, both of the end surfaces and the gap left on a part of the side wall are formed. A source gas for forming a deposited film and microwave energy are supplied into the film formation space from any location, and the gas is exhausted, thereby confining the microwave plasma in the film formation space and forming the side wall. A functional deposition film is formed on a strip-shaped member to be formed, and the strip-shaped member itself plays an important function as a structural material for isolating a film-forming space from an external atmosphere space not involved in film-forming. In addition, it 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 mainly formed in the film forming space. It functions only as a member on which a precursor for formation or the like is deposited, and does not function as a structural material constituting the film forming space as in the method of the present invention.

Further, in the conventional method such as RF plasma CVD, sputtering, 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. In addition, isolation from an external atmosphere space that is not involved in film formation is insufficient, and it cannot be said that the material functions as a structural material.

On the other hand, the method of the present invention uses a band-shaped member capable of functioning as a substrate or a support for forming a functional deposited film as a side wall of the film-forming space, exhibits a function as the structural material, and has a structure on the band-shaped member. This also enables continuous formation of a functional deposited film on the substrate.

In the method of the present invention, the side wall of the columnar space is formed by using the band-shaped member, and microwave energy is radiated almost uniformly in the width direction of the band-shaped member into the columnar space, so that the microwave is generated in the columnar space. By confining
Microwave energy is efficiently consumed in the columnar space, uniform microwave plasma is generated, and the uniformity of the deposited film formed is enhanced. 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 set in the film formation space 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. Condition is set to be different from 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 inside and outside 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. It is effective to provide a means that does not cause leakage. As a means for preventing microwave leakage, a gap portion connecting the inside and outside of the film forming space is sealed with a conductive member,
The hole diameter is preferably 波長 wavelength or less of the microwave to be used, more preferably 金 wavelength or less, and may be covered with a punching board, and the maximum dimension of the gap connecting the inside and outside of the film forming space is micro. It is desirable that the wavelength of the wave is preferably 以下 wavelength or less, more preferably 1 wavelength or less.
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, and has a great effect. .

Hereinafter, the configuration and features of the microwave plasma CVD apparatus of the present invention will be described in further detail in order.

According to the apparatus of the present invention, by being confined by the band-shaped member moving in the microwave plasma region, the precursor contributing to the formation of the deposited film generated in the microwave plasma region can be produced in a high yield on the substrate. Since the film can be captured on the upper surface and the deposited film can be continuously formed on the belt-shaped member, the utilization efficiency of the raw material gas for forming the deposited film can be dramatically improved.

Furthermore, since uniform microwave plasma is generated in the film forming space using the microwave applicator means of the present invention, the uniformity of the deposited film formed in the width direction of the band-shaped member is excellent. Needless to say, by continuously transporting the belt-shaped member substantially in the direction perpendicular to the longitudinal direction of the microwave applicator means, the uniformity of the deposited film formed in the longitudinal direction of the belt-shaped base band can be improved. Will also be excellent.

In addition, 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 the long belt-shaped member, and the interface characteristics can be formed. , It is possible to manufacture a laminated device having excellent characteristics.

In the apparatus of the present invention, when the band-shaped member functions as a structural material, the outside of the film formation chamber may be air, but a functional deposition film formed by the inflow of air into the film formation chamber. In this case, an appropriate air inflow prevention means may be provided. Specifically, an O-ring, a gasket, a helicflex, a mechanically sealed structure using a magnetic fluid, or the like, or a diluted 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.
When connecting the apparatus of the present invention to a plurality of other deposited film forming means and continuously depositing deposited films on the belt-like member, it is desirable to connect the respective apparatuses using gas gate means or the like. 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 depressurized state or a pressurized state. However, when the band-shaped member is greatly deformed by a pressure difference from the film forming chamber, an appropriate auxiliary structure is used. A material may be provided in the film forming chamber.
As the auxiliary structural material, it is desirable that the same shape as the side wall of the film forming chamber is formed of a wire, a thin plate, or the like made of metal, ceramic, 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 substantially shaded by the auxiliary structure. It is desirable that the projection area of the material on the strip is designed to be as small as possible.

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

As the material of the belt-shaped member suitably used in the method and the apparatus of the present invention, deformation at a temperature required at the time of forming a functional deposited film by a microwave plasma CVD method,
Less distortion, having the desired strength, it is also preferable to have conductivity, specifically stainless steel, aluminum and alloys, iron and its alloys, copper and its alloys such as thin metal sheets and The composites and metal thin films of different materials and / or SiO ₂ , Si ₃ N ₄ ,
An insulating thin film such as Al ₂ O ₃ or AlN that has been subjected to surface coating by sputtering, vapor deposition, plating, or the like. Also, polyimide, polyamide, polyethylene terephthalate,
Plate or deposit metal simple substance or alloy, transparent conductive oxide (TCO), etc. on the surface of a heat-resistant resin sheet such as epoxy or a composite of these with glass fiber, carbon fiber, boron fiber, metal fiber, etc. Spatter,
One that has been subjected to a conductive treatment by a method such as coating may be used.

As long as the thickness of the band-shaped member is within a range that exhibits a strength that maintains a curved shape formed at the time of conveyance by the conveyance means, the thickness is preferably as thin as possible in consideration of cost, storage space, and the like. Is desirable. Specifically, 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.However, it is preferable to use a relatively thin metal plate to reduce the thickness. However, a desired strength is easily obtained.

Further, the width dimension of the band-shaped member is preferably such that when the microwave applicator is used, the uniformity of the microwave plasma in the longitudinal direction is maintained, and the curved shape is maintained. More specifically, it is preferable that the thickness be 5 cm to 100 cm, more preferably 10 cm to 80 cm.

Furthermore, the length of the belt-shaped member is not particularly limited, and may be a length that can be wound up in a roll shape, and a longer one is made longer by welding or the like. There may be.

In the apparatus of the present invention, as the means for supporting and transporting the belt-like member while continuously bending the belt-like member, the belt-like member does not sag during transportation, wrinkles, lateral displacement, etc.
It is necessary to keep its curved shape 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. Giving a driving force to at least one of the rollers for
The belt-shaped member is transported in the longitudinal direction while maintaining the 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 leek-like one having a saw-tooth-shaped projection provided around it may be used.

Regarding the shape of the support / transport ring, in forming a curved shape, it is preferable that the shape is preferably circular. However, even if it is elliptical, square, or polygonal, the shape is continuously constant. There is no particular problem as long as it has a holding mechanism. Maintaining a constant transport speed is an important point in transporting the curved shape without causing slack, wrinkles, lateral displacement and the like. Therefore, the support
It is preferable that the transport mechanism is provided with a mechanism for detecting the transport speed of the belt-like member and a transport speed adjusting mechanism to which feedback is applied. These mechanisms also have a great effect on controlling the film thickness in manufacturing a semiconductor device.

In addition, the supporting / transporting ring is disposed in the microwave plasma region, although the degree of the exposure is varied depending on the 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 a material 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 obtained by molding a single or composite 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 adhered to the support / transport ring is preferably removed before peeling, scattering, etc. occur, and a chemical or physical method such as wet etching after dry etching or decomposition in a vacuum or bead blasting is performed. Is desirably removed.

The support / transport roller is designed to have a larger area in contact with the belt-shaped member than the support / transport ring, and thus has a higher heat exchange rate with the belt-shaped member. 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, the set temperatures of at least one pair of supporting / transporting rollers may be different. Furthermore,
The incorporation of a transport tension detecting mechanism for the belt-like member in the support / transport roller is also effective in keeping the transport speed constant.

Further, it is preferable that a crown mechanism is provided on the support / transport roller in order to prevent the belt-shaped member from bending, twisting, laterally displacing, and the like at the time of 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 both end surfaces of the columnar deposition chamber formed with the strip-shaped member as a side wall is substantially circular, elliptical, square,
The position where the microwave applicator means is disposed is substantially in the vicinity of the center of the shape, which is a polygonal shape or the like. It is desirable to increase the uniformity of the film. Also, 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 thickness of the deposited film to be 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, and the utilization efficiency of the source gas for forming the deposited film is determined. Is done.
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 source gas used,
Pressure, microwave radiation of microwave applicator,
It is determined by the correlation between the transmission capacity and the total volume of the microwave plasma region, and is difficult to define unambiguously.

When the band-shaped member is used as a substrate for a solar cell, when the band-shaped member is electrically conductive such as a metal, the band-shaped member may be directly used as an electrode for extracting current, or is electrically insulating such as a synthetic resin. In this case, Al, Ag, Pt, Au, Ni, Ti, Mo, W, Fe, V, Cr, Cu, stainless steel, brass, nichrome, SnO ₂ , In ₂ O _{3 , ZnO, SnO 2 -In 2 O} 3 (IT
It is desirable that a so-called metal simple substance or alloy such as O) and a transparent conductive oxide (TCO) are subjected to a surface treatment in advance by a method such as plating, vapor deposition, sputtering or the like to form an electrode for current extraction.

Of course, even if the strip-shaped member is made of an electrically conductive material such as metal, it is possible to improve the reflectance of long-wavelength light on the substrate surface or to interdiffuse constituent elements between the substrate material and the deposited film. 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 the occurrence of a short circuit or forming an interference layer for preventing a 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.

Further, the surface property of the belt-shaped 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 the maximum height (Rmax) is preferably 50.
By setting the angle between 0 ° and 5000 °, light reflection on the surface becomes irregular reflection, and the optical path length of light reflected on the surface is increased.

The microwave permeable member is provided at a distal end portion of the microwave applicator means, separates a vacuum atmosphere in the film forming chamber from outside air in which the microwave applicator means is installed, and exists between the inside and outside thereof. The structure is designed to withstand a certain pressure difference. Specifically, it is desirable that the cross-sectional shape of the microwave in the traveling direction is preferably circular, square, elliptical, flat, bell jar, doublet, or conical.

In addition, the thickness of the microwave transmitting member in the direction in which the microwave travels is determined in consideration of the dielectric constant of the material to be used, so that the reflection of the microwave is minimized.
It is desirable to be designed, for example, if it is a flat plate, it is preferable to make it approximately equal to half the 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, boron nitride,
Glass such as silicon carbide or fine ceramics may be used.

Further, it is preferable that the microwave transmitting member is uniformly cooled in order to prevent heat deterioration (cracking, 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, oil, freon, or the like. The microwave transmitting member may be cooled by a cooling medium such as the above, 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 the deposited film enters the film-forming chamber formed by the belt-shaped member. If the amount of radiation of microwave energy decreases and the amount of change increases significantly compared to immediately after the start of discharge, not only is maintenance of the microwave plasma itself difficult, but also the deposition rate of the deposited film to be formed In some cases, and changes in characteristics and the like may occur. 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 wet-etched or mechanically removed. For example, it may be peeled off and reused, 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 to convert the source gas for forming a deposited film introduced from the gas introducing means into plasma and maintain it. It has a structure that can be used.

Specifically, it is preferable to use a microwave transmission waveguide in which the microwave permeable member is attached to a tip 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. Further, the microwave transmission mode in the microwave applicator means to efficiently transmit microwave energy in the film forming chamber and stably generate, maintain, and control 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, it can be used by appropriately selecting microwave plasma generation conditions such as a source gas, pressure, and microwave power to be used. When the transmission mode is designed to be a single mode, for example, TE ₁₀ mode, TE ₁₁
Mode, eH ₁ mode, TM ₁₁ mode, there may be mentioned a TM ₀₁ mode or the like, preferably TM ₁₀ mode, TE ₁₁ mode, eH ₁ mode is 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 match. Is desirable. The type of the waveguide is appropriately selected depending on the frequency band (band) and mode of the microwave to be used, and it is preferable that at least the cutoff frequency is lower than the frequency to be used. JIS, EIAJ, IEC, JAN and other standards of square waveguide, circular waveguide, elliptical waveguide, etc., 2.45GH
In-house standards for microwaves of z include those having a square cross section and an inner diameter of 96 mm x 27 mm.

In the apparatus of the present invention, since microwave energy supplied from a microwave power supply is efficiently radiated into the film forming chamber through the microwave applicator means, there is a problem regarding a reflected wave caused by a so-called microwave applicator. It is easy to avoid, and in a microwave circuit, it is possible to maintain a relatively stable discharge without using a microwave matching circuit such as a three-stub tuner or an EH tuner. When a strong reflected wave is generated due to abnormal discharge or the like, it is desirable to provide the microwave matching circuit for protecting a microwave power supply.

In the apparatus of the present invention, a gap is left between the bending start end forming unit and the bending end end forming unit in the film forming chamber, and the raw material gas is exhausted from the gap. The gap is designed to be maintained at a predetermined reduced pressure, but the dimensions of the gap are designed so that sufficient exhaust conductance is obtained and microwave energy radiated into the film formation chamber does not leak out of the film formation chamber. Need to be done.

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

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

Further, the maximum dimension of the opening width in the longitudinal direction of the band-shaped member in the gap left between the bending start end forming means and the bending end end forming means is to prevent leakage of microwave energy from the gap. Preferably, the wavelength of the microwave is 1 /
It is desirable that the wavelength be 2 wavelengths or less, more preferably 1/4 wavelength or less.

In the device of the present invention, when a plurality of the microwave applicator means are arranged to face each other, the microwave energy radiated from one microwave applicator means is received by the other microwave applicator means. The received microwave energy reaches the microwave power supply connected to the other microwave applicator means, thereby damaging the microwave power supply or causing an abnormality in microwave oscillation. Must be arranged so as not to exert

Specifically, the microwave applicator means is disposed 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 waveguides are 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 radiating the microwave energy from only one of the two end faces of the film forming chamber, it is necessary to prevent leakage of the microwave energy from the other end face, The end face is sealed with a conductive member, or a wire mesh whose hole diameter is preferably 1/2 wavelength or less, more preferably 1 wavelength or less of the wavelength of the microwave used,
It is desirable to cover with a punching board or the like.

In the apparatus of the present invention, the film formation chamber and / or the isolation container are separated from a vacuum container having another film formation means and a vacuum atmosphere, and the belt-shaped member is continuously conveyed through the inside thereof. The gas gate means is suitably used for the above. 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. Thus, the basic concept can employ the gas gating means disclosed in U.S. Pat. No. 4,438,723, but its capabilities need to be further improved. Specifically, it is necessary to withstand the pressure differential up to 10 ⁶ times, as an exhaust pump large oil diffusion pump exhaust capability, turbo molecular pump, such as a mechanical booster pump is preferably used. In addition, the cross-sectional shape of the gas gate is a slit shape or a shape similar thereto, and the dimensions thereof are calculated and designed 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 in order to enhance the separation ability, and examples thereof include a rare gas such as Ar, He, Ne, Kr, Xe, and Rn or a diluent gas for forming a deposited film such as H ₂ . The flow rate of the gate gas is appropriately determined depending on the conductance of the entire gas gate, the capacity of the exhaust pump to be used, and the like. However, a pressure gradient generally shown in FIGS. 10 (a) and 10 (b) may be formed. In FIG. 10 (a), since there is a point where the pressure becomes maximum almost at the center of the gas gate, the gate gas flows from the center of the gas gate to the vacuum vessel side on both sides, and in FIG. Since there is a point at the center where the pressure is minimum,
The gate gas is exhausted from the center 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.

In the apparatus of the present invention, the deposition film forming means disposed in another vacuum vessel connected to the isolation vessel by the gas gate means includes RF plasma CVD, sputtering and reactive sputtering, and ion plating. Means for realizing a method used for forming a so-called functional deposited film, such as a plating method, a photo CVD method, a thermal CVD method, a MOCVD method, an MBE method, and an HR-CVD method. And, of course, it is also possible to connect the means of the microwave plasma CVD method of the present invention and 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 device of the present invention is preferably 2.45 GHz, which is preferably used for consumer use, but is relatively easily available even in other frequency bands. Anything can be used. In addition, in order to obtain a stable discharge, the oscillation mode is preferably a so-called continuous oscillation, and the ripple width thereof is preferably within 30%, more preferably within 10% in a used output region.

In the apparatus of the present invention, the continuous formation of the deposited film without exposing the film forming chamber and / or the isolation container to the atmosphere can prevent impurities from being mixed on the basis of stable characteristics of the formed deposited film. It is valid. 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.

Hereinafter, a specific processing method will be described with reference to the drawings.

9 (1) (i) to 9 (4) (x)
The figure shows a schematic view for explaining the outline of the band-shaped member processing chamber and the operation at the time of film formation of the band-shaped member and the like.

In FIG. 9, reference numeral 901a denotes a band-shaped member processing chamber (A) provided on the feeding side of the band-shaped member, and 901b denotes a band-shaped member processing chamber (B) provided on the winding side of the band-shaped substrate. Viton rollers 907a, 907b, cutting blades 908a, 908
b, welding jigs 909a and 909b are stored.

That is, FIG. 9 (part 1) (i) shows a state at the time of normal film formation, in which the belt-shaped member 902 is moved in the direction of the arrow in the figure.
The roller 907a, the cutting blade 908a, and the welding jig 909a do not contact the belt-shaped member 902. Reference numeral 910 denotes a connecting means (gas gate) for connecting to a belt-shaped member storage container (not shown), and reference numeral 911 denotes a connecting means (gas gate) for connecting to a vacuum container (not shown).

FIG. 9 (part 1) and (ii) show a first step for exchanging a new band-shaped member after the film-forming step on one band of the band-shaped member is completed. First, the belt-shaped member 902 is stopped,
The roller 907a is moved in the direction of the arrow from the position shown by the dotted line in the drawing to make close contact with the band-like member 902 and the wall of the band-like member processing chamber 901a. In this state, the band-shaped member storage container and the film forming chamber are air-tightly separated. Next, the cutting blade 908a is operated in the direction of the arrow in the figure to cut the band-shaped member 902. This cutting blade 908a is mechanical,
The belt-shaped member 902 can be electrically or thermally cut by any one of them.

FIG. 9 (part 1) (iii) shows a state in which the strip-shaped member 903 cut and separated is wound up toward the strip-shaped member storage container.

The above-described cutting and winding steps may be performed in either a vacuum state or an atmospheric pressure leak state in the belt-shaped member storage container.

FIG. 9 (part 2) (iv) shows a process in which a new band-shaped member 904 is fed in and connected to the band-shaped member 902. The ends of the belt-shaped members 904 and 902 are brought into contact with each other and a welding jig is formed.
Welded connection at 909a.

In FIG. 9 (part 2) and (v), the inside of the band-shaped member storage container (not shown) is evacuated, and after the pressure difference from the film forming chamber is sufficiently reduced, the roller 907a is moved to the band-shaped member 902 and the band-shaped member processing chamber. (A) shows a state in which the belt-shaped members 902 and 904 are being wound away from the wall of 901a.

 Next, the operation on the winding side of the belt-shaped member will be described.

FIG. 9 (part 3) and (vi) show the state at the time of normal film formation, but each jig is arranged substantially symmetrically as described with reference to FIG. 9 (part 1) and (i).

FIG. 9 (part 3) (vii) shows that after the film forming process on one band of the band-shaped member is completed, this is taken out and replaced with an empty bobbin for winding the band-shaped member subjected to the next film forming process. The steps for performing the steps are shown.

First, the belt-shaped member 902 is stopped, and the roller 907b is moved in the direction of the arrow from the position shown by the dotted line in the figure, so that the belt-shaped member 90
2 and in close contact with the wall of the band-shaped member processing chamber 901b. In this state, the band-shaped member storage container and the film forming chamber are air-tightly separated. Next, the cutting blade 908b is operated in the direction of the arrow in FIG.
Cut 2 The cutting blade 908b is made of any of those capable of mechanically, electrically, and thermally cutting the strip-shaped base 902.

FIG. 9 (part 3) (viii) shows a state in which the strip-shaped member 905 that has been cut and separated after the film-forming step is wound up toward the strip-shaped member storage container.

The above-described cutting and winding steps may be performed in either a vacuum state or an atmospheric pressure leak state in the belt-shaped member storage container.

FIG. 9 (part 4) (x) shows a step in which the pre-winding strip 906 attached to the new winding bobbin is fed in and connected to the strip 902. The end portions of the preliminary winding band member 906 and the band member 902 are brought into contact with each other, and are connected by welding with a welding jig 906b.

In FIG. 9 (part 4) (X), the inside of the band-like member storage container (not shown) is evacuated, and after the pressure difference with the film forming chamber is sufficiently reduced, the roller 907b is moved to the band-like member 902 and the band-like member processing. It shows a state in which the belt-shaped members 902 and 906 have been wound away from the wall of the chamber (B) 901b.

As the functional deposited film continuously formed in the method and the apparatus of the present invention, a so-called group IV semiconductor thin film such as Si, Ge, C, or a so-called group IV alloy semiconductor such as SiGe, SiC, SiSn Thin film, GaAs, GaP, GaSb, InP, InAs, etc., so-called II
Group IV compound semiconductor thin film, and ZnSe, ZnS, ZnTe, CdS, CdS
e, a so-called II-VI compound semiconductor thin film such as CdTe.

As the material gas for forming a functional deposited film used in the method and the apparatus of the present invention, hydrides, halides, organometallic compounds, etc. of the constituent elements of the above-mentioned various semiconductor thin films are preferably introduced into the film formation chamber in a gaseous state. Those that can be introduced in are selected and used.

Of course, these raw material compounds can be used alone or in combination of two or more. These starting compounds are rare gases such as He, Ne, Ar, Kr, Xe, and Rn, and H ₂ , HF, and HCl.
May be introduced as a mixture with a diluent gas such as

Further, the semiconductor thin film formed continuously can perform valence electron control and forbidden band width control. Specifically, a raw material compound containing an element serving as a valence electron controlling agent or a forbidden band width controlling agent may be used alone or mixed with the deposited film forming raw material gas or the diluent gas and introduced into the film formation chamber. .

The raw material gas for forming a deposited film and the like are formed by a gas introduction pipe having a single or a plurality of gas discharge holes at a tip end thereof disposed in a columnar film forming chamber formed by the band-shaped member. It is uniformly discharged into the film chamber and turned into plasma by microwave energy to form a microwave plasma region. As the material constituting the gas introduction tube, a material that is not damaged in microwave plasma is preferably used. Specific examples include heat-resistant metals such as stainless steel, nickel, titanium, tungsten, vanadium, and nichrome, and those obtained by spraying ceramics such as alumina and silicon nitride on these metals.

In the apparatus of the present invention, the deposited film forming source gas introduced into the columnar film forming chamber from the gas introduction pipe is partially or entirely decomposed to generate a deposited film forming precursor,
Although a deposited film is formed, an undecomposed raw material gas or a gas having a different composition due to decomposition needs to be quickly 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 interval is preferably 1/2 wavelength or less of the wavelength of the microwave used, in order to prevent microwave leakage, more preferably It is desirable that the wavelength be equal to or less than 1/4 wavelength.

(Example of device)

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 shows a schematic perspective schematic view of a microwave plasma CVD apparatus of the present invention.

Reference numeral 101 denotes a belt-shaped member, and rollers 102 and 103 for supporting and transporting.
The film is conveyed in the direction of the arrow () in the figure while continuously maintaining a cylindrical shape by the support / transfer rings 104 and 105, and the film formation chamber 116 is continuously formed. 106a to 106e are temperature control mechanisms for heating or cooling the belt-shaped member 101,
Temperature control is performed independently of each other.

In this device example, the microwave applicators 107, 10
8 are provided facing each other, the microwave transmitting members 109 and 110 are provided at the tip portions thereof, and the rectangular waveguides 111 and 112 are respectively provided on the surfaces including the center axis of the supporting / transporting rollers. On the other hand, they are arranged such that the planes including the long sides are not perpendicular 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 supporting / transporting ring 104 for the purpose of explanation, but is arranged in the direction of the arrow in the figure when forming a deposited film.

113 is a gas introduction pipe, and 114 is an exhaust pipe, which is connected to an exhaust pump (not shown). 115a and 115b are isolation passages that are provided when the apparatus of the present invention is connected to a container or the like including other film forming means.

The support / conveyance rollers 102 and 103 have a built-in conveyance conveyance detection mechanism and a tension detection adjustment mechanism (both not shown).
While maintaining the conveying degree of the belt-shaped member 101 constant, its curved shape is also kept constant.

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

FIG. 2 is a schematic sectional view for specifically explaining the microwave applicator means 107 and 108.

Reference numeral 200 denotes a microwave applicator, which is a rectangular waveguide 208 from a microwave power supply (not shown) from the left arrow direction in the figure.
The microwave is transmitted via the.

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

In this device example, the inner shape of the inner cylinder 204 is cylindrical, and the inner diameter and the length in the traveling direction of the microwave 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 shape of the inner cylinder 204 may be a prismatic shape.

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

The shape of the isolation container is not particularly limited as long as each of the constituent jigs shown in the device example 1 can be incorporated, but a cubic shape, a rectangular parallelepiped shape, a cylindrical shape, or the like is suitably used. 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. . In addition, 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, a device having the same configuration as in Apparatus Example 1 except that the shape of the microwave applicator is changed to a prismatic shape can be given. 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 In this apparatus example, there can be mentioned an apparatus having the same configuration as in apparatus example 2, except that the prismatic microwave applicator means used in apparatus example 3 is used.

Apparatus Examples 5 and 6 In this apparatus example, there can be mentioned those having the same configuration as in Apparatus Examples 1 and 2 except that an elliptical column-shaped microwave applicator is used instead of the cylindrical microwave applicator.

Apparatus Example 7 In this apparatus example, as shown in FIG. 3, vacuum containers 301 and 30 for feeding and winding the belt-shaped member 101 into the microwave plasma CVD apparatus for forming a deposited film shown in Apparatus Example 2.
A device in which 2 is connected using gas gates 321 and 322 can be mentioned.

300 is an isolation container, 303 is a bobbin for feeding a belt-like member,
Reference numeral 304 denotes a bobbin for winding the belt-like member, and the belt-like member is conveyed in a direction indicated by an arrow in FIG. Of course, it is also possible to convey the sheet by reversing them. Further, in the vacuum vessels 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. Reference numerals 312 and 313 denote temperature adjusting mechanisms used for preheating or cooling the belt-shaped member. 307, 308, 309 are throttle valves for adjusting the displacement, 310, 311, 320 are exhaust pipes,
Each is connected to an exhaust pump (not shown). 314,31
5 is a pressure gauge, 316,317 is a gate gas inlet pipe, 318,319
Reference numeral denotes a gate gas exhaust pipe, and a gate gas and / or a source gas for forming a deposited film are exhausted by an exhaust pump (not shown).

Apparatus Example 8 In this apparatus example, as shown in FIG. 4, two more microwave plasma CVs of the present invention are added to the apparatus shown in Apparatus Example 7.
Isolation container 300-a with built-in deposition film forming equipment by D method,
One that can connect 300-b to both sides to form a stacked device can be mentioned.

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.

401,402,403,404 are gas gates, 405,406,407,408
, 409, 410, 411, 412 are gate gas exhaust pipes.

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

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

Apparatus Example 13 In this apparatus example, as shown in FIG. 5, two conventional RF plasma CVD apparatuses are connected to both sides of the apparatus shown in Apparatus Example 7 so that a stacked device can be manufactured. Can be cited.

Here, 501 and 502 are vacuum vessels 503 and 504 are cathode electrodes for RF application, 505 and 506 are gas introduction tubes and heaters, 507 and 508 are halogen lamps for heating a substrate, 509 and 510 are anode electrodes, and 51 is an anode electrode.
1,512 is an exhaust pipe.

Apparatus Examples 14 and 15 In this apparatus example, a microwave applicator is provided only on one end surface of one side of the film forming chamber in a case where a relatively narrow band-shaped member is used in the apparatus shown in the apparatus examples 1 and 2. Can be mentioned. However, in this case, the other end face has a wire mesh for preventing microwave leakage,
A patching board, a thin metal plate and the like are provided.

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

Further, there may be mentioned a device in which the devices shown in the device example 8 are connected in a double or triple connection, a device in which a deposition film forming means by the RF plasma CVD method is mixed and connected.

Further, in the apparatus shown in the apparatus example 1 or 2, two pairs or more microwave applicators are disposed on both end faces of the film forming chamber to form a larger microwave plasma region, and the transfer rate of the belt-shaped member is increased. There is no change, and an apparatus that can form a relatively thick functional deposited film 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. 8A to 8D schematically show typical examples of the layer structure.

In the example shown in FIG. 8A, the lower electrode 80 is
2, n-type semiconductor layer 803, i-type semiconductor layer 804, p-type semiconductor layer 8
05, a photovoltaic element 800 in which a transparent electrode 806 and a collecting electrode 807 are formed in this order. In this photovoltaic element, it is assumed that light enters from the transparent electrode 806 side.

In the example shown in FIG. 8B, 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 on a light-transmitting support 801. This is the photovoltaic element 800 '. In this photovoltaic element, it is assumed that light is incident from the light-transmitting support 801 side.

An example shown in FIG. 8C is a so-called tandem configuration in which two pin-junction photovoltaic elements 811 and 812 using two types of semiconductor layers having different band gaps and / or layer thicknesses as i-layers are stacked. Type photovoltaic element 813. Reference numeral 801 denotes a support, and the lower electrode 802, the n-type semiconductor layer 803, the i-type semiconductor layer 804, the p-type semiconductor layer 805, the n-type semiconductor layer 808, the i-type semiconductor layer 809, the p-type semiconductor layer 810, and the transparent electrode 806 And current collecting electrode 8
07 are laminated in this order, and it is assumed that light is incident from the transparent electrode 806 side in this photovoltaic element.

The example shown in FIG. 8 (D) is a so-called so-called “layered structure” in which three pin-junction photovoltaic elements 820, 821 and 823 using three kinds of semiconductor layers having different band gaps and / or layer thicknesses as i-layers are stacked. This is a triple type photovoltaic element 824. 801
Denotes a support, and the lower electrode 802, the n-type semiconductor layer 803, the i-type semiconductor layer 804, the p-type semiconductor layer 805, the n-type semiconductor layer 814, i
Semiconductor layer 815, p-type semiconductor layer 816, n-type semiconductor layer 817,
The i-type semiconductor layer 818, the p-type semiconductor layer 819, the transparent electrode 806, and the current collecting electrode 807 are stacked in this order, and it is assumed that light is incident from the transparent electrode 806 side in this photovoltaic element. .

In each of the photovoltaic elements, the n-type semiconductor layer and the p-type semiconductor layer can be used in a different order of lamination depending on the purpose.

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

Support The support 801 used in the present invention is preferably made of a material that is flexible and capable of forming a curved shape, and may be conductive or electrically insulating. Good. Further, they may be translucent or non-translucent, but when light is incident from the support 801 side, they are translucent. It is necessary.

Specifically, the band-shaped member used in the present invention can be mentioned, by using the band-shaped member,
It is possible to reduce the weight, improve the strength, and reduce the transportation space of the manufactured solar cell.

Electrodes In the present photovoltaic element, 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 The lower electrode 802 used in the present invention has a different surface to which light for generating photovoltaic power is irradiated depending on whether the material of the support 801 is translucent or not (for example, When 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 a layer configuration as shown in FIGS. 8A, 8C and 8D, it is provided between the support 801 and the n-type semiconductor layer 803. 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. 8 (B), a light-transmitting support 801 is used, and light enters from the support 801 side. Therefore, for the purpose of current extraction and light reflection at the electrode, A lower 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.

As electrode materials, Ag, Au, Pt, Ni, Cr, Cu, Al, Ti, Zn, Mo,
Metals such as W or alloys thereof are mentioned, and thin films of these metals are formed by vacuum evaporation, electron beam evaporation, sputtering, or the like. Further, 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 prevention 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 small resistance value so that the lower electrode provided with the semiconductor layer interposed therebetween. To prevent a short circuit generated due to a defect such as a pinhole between 802 and the transparent electrode 806,
In addition, there can be obtained an effect of generating multiple interference by the thin film and confining the incident light in the photovoltaic element.

(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 a white fluorescent lamp into the semiconductor layer. The sheet resistance is desirably 100Ω or less so that the output of the photovoltaic element does not become a resistance component. As a material having such properties, Sn
Metal oxides such as O ₂ , In ₂ O ₃ , ZnO, CdO, Cd ₂ SnO ₄ , ITO (In ₂ O ₃ + SnO ₂ ), and metals such as Au, Al, Cu etc. Metal thin film and the like. 8th transparent electrode
In FIGS. 8A, 8C and 8D, they are stacked on the p-type semiconductor layer 805, and in FIG. 8B, they are stacked on the substrate 801. It is necessary to choose a good one. These fabrication methods include:
A resistance heating evaporation method, an electron beam heating evaporation method, a sputtering method, a spray method, or the like can be used, and is appropriately selected as desired.

(Iii) Current collecting electrode The current collecting electrode 807 used in the present invention is a transparent electrode 8
06 is provided on the transparent electrode 806 for the purpose of reducing the surface resistance value. Ag, Cr, Ni, Al, Ag, Au, Ti, Pt,
Examples include thin films of metals such as Cu, Mo, and W or alloys thereof. These thin films can be stacked and used. In addition, to ensure a sufficient amount of light incident on the semiconductor layer,
The shape and area are appropriately designed.

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

Further, as a sheet resistance value, preferably 50Ω or less,
More preferably, it is desirably 10Ω or less.

i-type semiconductor layer As the semiconductor material constituting the i-type semiconductor layer suitably used in the photovoltaic element manufactured by the present invention, a-Si: H, a-Si: F, a-Si: H: F , a-SiC: H, a-SiC: F, a
−SiC: H: F, a−SiGe: H, a−SiGe: F, a−SiGe: H: F, poly-Si:
In addition to so-called group IV and group IV alloy-based semiconductor materials such as H, poly-Si: F, and poly-Si: H: F, so-called compound semiconductor materials such as II-VI and III-V are included.

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 according to the present invention, the semiconductor material constituting the above-mentioned i-type semiconductor layer Obtained by doping a valence electron controlling agent.

(Production example)

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 The continuous microwave plasma CVD apparatus (FIG. 3) shown in Apparatus Example 7 was used to continuously deposit an amorphous silicon film.

First, a SUS430BA strip-shaped substrate (width 45 cm ×
A wound bobbin 303 having a length of 200 m and a thickness of 0.25 mm) is set, and the substrate 101 is placed on the gas gate 321 and the isolation container 300.
The tension was adjusted to the extent that there was no slack by passing the vacuum container 302 having the substrate take-up mechanism through the medium transfer mechanism and further through the gas gate 322.

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 activated and evacuated to about 10 ⁻³ Torr, and then the temperature control mechanisms 106a and 106b are further activated. While maintaining the surface temperature of the belt-like member at 250 ° C., the pressure was reduced to 5 × 10 ⁻⁶ Torr or less by an oil diffusion pump (not shown) (HS-32 manufactured by Varian).

Table 7 shows the conditions such as the shape and the curved shape of the microwave applicator.

When sufficient degassing was performed, 450 sccm of SiH ₄ , 5 sccm of SiF ₄ and 100 sccm of H ₂ were introduced from a gas introduction pipe (not shown), and the opening of the throttle valve attached to the oil diffusion pump was adjusted. Pressure in the isolation container 300 to 5 mTorr
Held. When the pressure becomes stable, 2.45GH (not shown)
0.85kW × 2 effective power from microwave power supply of z specification
Applicator provided with a pair of microwaves facing each other
The light was emitted into the film formation chamber from 107 and 108. Immediately, the introduced source gas was turned into plasma to form a plasma region, and the plasma region did not leak out of the gap between the supporting / transporting rollers 102 and 103 toward the isolation container. Also, microwave leakage was not detected.

Therefore, the supporting / transporting rollers 102 and 103 and the supporting / transporting rings 104 and 105 (both driving mechanisms are not shown) were activated, and the transport speed of the substrate 101 was controlled to be 0.6 m / min.

The gas gates 321 and 322 have gate gas inlet pipes 316 and 3 respectively.
Flow 50sccm H ₂ gas as the gate gas from 17, the exhaust hole 3
The gas was exhausted from an oil diffusion pump (not shown) from 18, 18 and 318, and the internal pressure of the gas gate was controlled to 1 mTorr.

A deposited film was formed continuously for 30 minutes after the start of transport. Since a long substrate was used, another deposited film was continuously formed after the end of the present production example, and after all the depositions were completed, the substrate was taken out by cooling and formed in the present production example. When the thickness distribution of the deposited film on the substrate was measured in the width direction and the longitudinal direction, it was within 5%, and the deposition rate was 125 ° / sec on average. In addition, a part of it is cut out and FT-IR (1720X manufactured by Perkin-Elmer)
It was measured infrared absorption spectrum by a reflection method using the observed absorption at 2000 cm ^-1 and ^{630cm -1 a-Si: H:} F
The absorption pattern was unique to the film. In addition, RHEED (JEM-1
(00SX, manufactured by JEOL Ltd.), the film was evaluated for crystallinity and found to be halo and amorphous. The amount of hydrogen in the film was determined using a hydrogen-in-metal analyzer (EMGA-1100, manufactured by HORIBA, Ltd.) and found to be 20 ± 2 atomic%.

Production Example 2 Following the deposition film forming step performed in Production Example 1, the introduction of the used raw material gas was stopped, and the internal pressure of the isolation container 300 was evacuated to 5 × 10 ⁻⁶ Torr or less. As shown), SiH ₄ 100sccm, GeH ₄ 80sccm, SiF ₄ 3s
ccm, introducing H ₂ 100 sccm, holding the internal pressure to 10 mTorr,
Microwave power is 0.5kW × 2 and transfer speed is 30cm / min
Amorphous silicon germanium films were continuously deposited under the same deposition film forming conditions except that the above conditions were adopted.

After the end 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 averaged 49Å / sec.

Also, cut out a part, it was measured infrared absorption spectrum by a reflection method using FT-IR (Perkin Elmer 1720X), 2000cm ^-1, 1880cm ^-1 and 630cm
Absorption was observed at ^-1 and the absorption pattern was unique to the a-SiGe: H: F film. Furthermore, when the crystallinity of the film was evaluated by RHEED (JEM-100SX, manufactured by JEOL Ltd.), it was found that the film was halo and amorphous. In addition, hydrogen analyzer in metal (EMGA-110
0, manufactured by Horiba, Ltd.), the amount of hydrogen in the film was determined to be 15 ± 2 atomic%.

Production Example 3 Following the deposition film forming step performed in Production Example 1, the introduction of the used raw material gas was stopped, and the internal pressure of the isolation container 300 was evacuated to 5 × 10 ⁻⁶ Torr or less. than _{shown), SiH 4 140sccm, CH 4} 20sccm, SiF 4 5sc
cm, H ₂ 300 sccm were introduced, the internal pressure was maintained at 22 mTorr, and the microwave power was changed to 1.1 kW × 2, and the amorphous silicon carbide film was continuously deposited under the same deposition film forming conditions.

After the end 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 averaged 42Å / sec.

Further, a part thereof was cut out, and an infrared absorption spectrum was measured by a reflection method using FT-IR (1720X manufactured by Perkin-Elmer Co., Ltd.) to find that it was 2080 cm ⁻¹ , 1250 cm ⁻¹ , 960 c
m ^-1, a-SiC observed absorption at 777cm ^-1 and 660cm ^-1: H: F
The absorption pattern was unique to the film. In addition, RHEED (JEM-1
(00SX, manufactured by JEOL Ltd.), the film was evaluated for crystallinity and found to be halo and amorphous. The amount of hydrogen in the film was determined using a hydrogen-in-metal analyzer (EMGA-1100, manufactured by HORIBA, Ltd.) to be 14 ± 2 atomic%.

Production Example 4 Following the deposition film forming process performed in Production Example 1, the introduction of the used raw material gas was stopped, and the internal pressure of the isolation container 300 was evacuated to 5 × 10 ⁻⁶ Torr or less. From the illustration), 220 sccm of SiH ₄ , 40 sccm of BF ₃ (3000 ppm H ₂ dilution), 25 sccm of SiF ₄ and 600 sccm of H ₂ were introduced, and the internal pressure was increased.
A continuous deposition of a p-type microcrystalline silicon film was performed under the same deposition film forming conditions except that the pressure was maintained at 7 mTorr and the microwave power was 1.2 kW × 2.

After the end 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 averaged 60Å / sec.

Also, cut out a part, it was measured infrared absorption spectrum by a reflection method using FT-IR (Perkin Elmer 1720X), observed absorption at 2100 cm ^-1 and 630cm ^-1 μC-Si: H : Absorption pattern peculiar to the F film.
Further, when the crystallinity of the film was evaluated by RHEED (JEM-100SX, manufactured by JEOL Ltd.), it was found to be ring-shaped and non-oriented polycrystalline. In addition, hydrogen analyzer in metal (EMGA-110
0, manufactured by Horiba Seisakusho), the amount of hydrogen in the film was determined to be 4 ± 1 atomic%.

Production Example 5 Following the deposition film forming step performed in Production Example 1, the introduction of the used raw material gas was stopped, and the internal pressure of the isolation container 300 was evacuated to 5 × 10 ⁻⁶ Torr or less. From the illustration), SiH ₄ 320sccm, PH ₃ (1% H ₂ dilution) 27
sccm, SiF ₄ 5sccm, introducing H ₂ 5 sccm, a pressure 8mTorr
, And continuous deposition of an n-type amorphous silicon film was performed under the same deposition film forming conditions except that the microwave power was set to 0.8 kW × 2.

After the end 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 averaged 86Å / sec.

Further, a portion cut out, was measured infrared absorption spectrum by a reflection method using FT-IR (Perkin Elmer 1720X), absorption was observed at 2000 cm ^-1 and 630 cm ^-1, a-Si The absorption pattern was specific to the: H: F film. Furthermore, when the crystallinity of the film was evaluated by RHEED (JEM-100SX, manufactured by JEOL Ltd.), it was found that the film was halo and amorphous. The amount of hydrogen in the film was determined using a hydrogen in metal analyzer (EMGA-1100, manufactured by HORIBA, Ltd.).
tomic%.

Production Example 6 In Production Example 1, instead of the SUS430BA band-shaped substrate,
PET (polyethylene terephthalate) belt-like substrate (width 45c)
m × length 100m × thickness 0.9mm) and the substrate surface temperature is 210
An amorphous silicon film was continuously deposited by exactly the same operation except that the temperature was changed to ° C.

The substrate was taken out after cooling, and the film thickness distribution was measured within the width direction and the longitudinal direction to be within 5%, and the deposition rate was 120 ° / sec on average. In addition, a part of it is cut out and FT-IR (1720X manufactured by Perkin-Elmer)
The use, by measurement of infrared absorption spectrum by the reference transmission method, observed absorption at 2000 cm ^-1 and ^{630cm -1, a-Si: H} : was absorbing pattern specific to F film. Further, the amount of hydrogen in the film was determined from the absorption attributed to Si-H near 2000 cm ^-1 and found to be 25 ± 2 atomic%.

Furthermore, when the crystallinity of the film was evaluated by RHEED (JEM-100SX, manufactured by JEOL Ltd.), it was found that the film was halo and amorphous.

The other 20 portions were randomly cut out, and for each of them, a comb-shaped Al-made gap electrode (width: 250 μm, length: 5 mm) was deposited by resistance heating evaporation, and AM-1 light (100 mW
/ cm ² ) Photocurrent value under irradiation and dark current value in dark
The light conductivity σp (S / cm) and the dark conductivity σd (S / cm) were measured using a 4140B,
0.5) × 10 ⁻⁵ S / cm and (1.5 ± 0.5) × 10 ⁻¹¹ S / cm.

Production Example 7 In this production example, a Schottky junction diode having the layer configuration shown in the schematic sectional view of FIG. 7 was produced using the apparatus shown in FIG.

Here, 701 is a substrate, 702 is a lower electrode, 703 is an n ⁺ type semiconductor layer, 704 is a non-doped semiconductor layer, 705 is a metal layer, 706,
Reference numeral 707 denotes a current extraction terminal.

First, a SUS430BA strip-shaped substrate similar to that used in Production Example 1 was set in a continuous sputtering apparatus, and a Cr (99.98%) electrode was used as a target to deposit a Cr thin film of 1300 mm.
A lower electrode 702 was formed.

Subsequently, the strip-shaped member was sent out in the vacuum vessel 301 of the continuous deposition film forming apparatus shown in FIG.
Set to 03, with the Cr thin film deposited side facing down, wrap the end around the winding bobbin 304 in the vacuum vessel 302 via the isolation vessel 300, and tension it so that it does not slack. Adjustments were made.

The conditions such as the curved shape of the substrate and the microwave applicator in this production example were the same as those shown in Table 7.

Thereafter, roughing and high vacuuming operations similar to those of Production Example 1 were performed by an exhaust pump (not shown) through the exhaust pipes 309, 310, and 311 of the respective vacuum vessels. At this time, the surface temperature of the belt-shaped member is
The temperature was controlled by the temperature control mechanisms 106a and 106b so that the temperature became 250 ° C.

When sufficient degassing is performed, 300 sccm of SiH ₄ , ₄ sccm of SiF ₄ , PH ₃ / H ₂ (1% H
₂ dilution) 44Sccm, introducing H ₄ 40 sccm, by adjusting the opening degree of the throttle valve 709, the internal pressure of the isolation container 300 held in 8 mTorr, where the pressure is stabilized, immediately 0.8kW from a microwave power supply (not shown) X2 microwaves were emitted from a pair of microwave applicators 107 and 108. The transfer was started at the same time when the plasma was generated, and the deposition operation was performed for 5 minutes while transferring from the left side to the right side in the drawing at a transfer speed of 60 cm / min. Thereby, n ⁺ as n ⁺ semiconductor layer 703
^{+ An} a-Si: H: F film was formed on the lower electrode 702.

During this time, H ₂ was flowed through the gas gates 321 and 322 as a gate gas at a flow rate of 50 sccm, and the gas was exhausted from an exhaust hole 318 by an exhaust pump (not shown).

Stop supplying microwaves and introducing raw material gas,
After stopping the conveyance of the belt-shaped member, the internal pressure of the isolation container 300 is reduced to 5 × 1
After evacuated to 0 ^-6 Torr or less, than again the gas introduction pipe to introduce _{SiH 4 320sccm, SiF 4 6sccm,} H 2 60sccm,
The opening degree of the throttle valve 309 is adjusted to maintain the internal pressure of the isolation container 300 at 6 mTorr. When the pressure is stabilized, a microwave of 0.7 kW × 2 is immediately supplied from a microwave power supply (not shown) to the pair of microwave applicators 107 and 108. More radiated. Transfer started at the same time as the plasma was generated, 60 cm
The stacking operation was performed for 5.5 minutes while transporting reversely from right to left in the figure at a transport speed of / min. This gives n ⁺
a as a non-doped semiconductor layer 704 on the a-Si: H: F film
-A Si: H: F film was laminated.

After all deposition operations are completed, supply of microwaves and supply of source gas is stopped, and transport of substrates is stopped.
The residual gas in 0 was exhausted, and the substrate was taken out after cooling.

A permalloy mask having a diameter of 5 mm was randomly adhered to 10 portions of the substrate, and an Au thin film as the metal layer 705 was vapor-deposited by 80 ° by an electron beam vapor deposition method. Then, the current extraction terminals 706 and 707 were bonded using a wire bonder.
The diode characteristics were evaluated using 0B.

As a result, good diode characteristics were shown, with a rectification ratio of about 6 digits at a diode factor n = 1.2 ± 0.05 and ± 1V.

Production Example 8 In this production example, a pin-type photovoltaic element having a layer structure shown in the schematic sectional view of FIG. 8A was produced using the apparatus shown in FIG.

The photovoltaic element has a photovoltaic device in which a lower electrode 802, an n-type semiconductor layer 803, an i-type semiconductor layer 804, a p-type semiconductor layer 805, a transparent electrode 806, and a collecting electrode 807 are formed in this order on a substrate 801. Element 800. In this photovoltaic element, the transparent electrode 8 was used.
It is assumed that light enters from the 06 side.

First, a PET-made strip-shaped substrate similar to that used in Production Example 6 was set in a continuous sputtering apparatus, and an Ag (99.99%) electrode was used as a target, and a 1000-mm Ag thin film was continuously formed.
1.2μm using ZnO (99.999%) electrode as target
Was deposited by sputtering to form a lower electrode 802.

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 7. Table 8 shows conditions such as the curved shape of the substrate in the isolation container 300 at this time.

In the isolation containers 300-a and 300-b, the n-type a-Si: H: F film and the p ⁺ -type μc were deposited under the deposition film forming conditions shown in Table 9.
-A Si: H: F film was formed.

First, microwave plasma is generated in each film forming chamber, and the belt-shaped member 101 is transported from the left side to the right side in the drawing at a transport speed of 55 cm / min when stabilized by discharge or the like, and continuously, n, i, p A mold semiconductor layer was formed by lamination.

After laminating and forming a semiconductor layer over the entire length of the belt-shaped member 101, take out after cooling, and further, with a continuous modularization device
A 35 cm × 70 cm solar cell module was continuously produced.

For the fabricated solar cell module, AM1.5 (100mW
/ cm ²⁾ was subjected to characteristic evaluation under optical irradiation, obtained from 8.3% or more in the photoelectric conversion efficiency, further variations in the characteristics among the modules was accommodated within 5%.

In addition, the rate of change of the photoelectric conversion efficiency from the initial value after 500 hours of continuous irradiation with AM1.5 (100 mW / cm ² ) light was measured.
Within 10%.

By connecting these modules, a 3 kW power supply system was made.

Production Example 9 In this production example, in the pin-type photovoltaic device produced in Production Example 8, an a-SiGe: H: F film was used instead of the a-Si: H: F film as the i-type semiconductor layer. Is shown.

The a-SiGe: H: F film was formed by the same operation and method as in Production Example 2 except that the transport speed was 52 cm / min and the surface temperature of the belt-shaped member was 200 ° C. The layers and the modularization process are performed by the same operation and method as in Production Example 8,
A solar cell module was manufactured.

For the fabricated solar cell module, AM1.5 (100mW
/ cm ² ) When the characteristics were evaluated under light irradiation, a photoelectric conversion efficiency of 7.3% or more was obtained, and the variation in characteristics between modules was within 5%.

In addition, the rate of change of the photoelectric conversion efficiency from the initial value after 500 hours of continuous irradiation with AM1.5 (100 mW / cm ² ) light was measured.
Within 10%.

By connecting these modules, a 3 kW power supply system was made.

Production Example 10 In this production example, an a-SiC: H: F film was used instead of the a-Si: H: F film as the i-type semiconductor layer in the pin-type photovoltaic device produced in Production Example 8. Here is an example.

The a-SiC: H: F film was formed by the same operation and method as in Production Example 3 except that the transfer speed was 50 cm / min and the surface temperature of the belt-shaped member was 200 ° C. The layers and the modularization process are performed by the same operation and method as in Production Example 8,
A solar cell module was manufactured.

For the fabricated solar cell module, AM1.5 (100mW
/ cm ²⁾ was subjected to characteristic evaluation under optical irradiation, obtained over 6.6% in photoelectric conversion efficiency had more variation in the characteristics among the modules accommodated within 5%.

In addition, the rate of change of the photoelectric conversion efficiency from the initial value after 500 hours of continuous irradiation with AM1.5 (100 mW / cm ² ) light was measured.
Within 10%.

These modules can be connected to create a 3 kW power supply system.

Production Example 11 In this production example, a photovoltaic element having a layer configuration shown in FIG. 11 (C) was produced. At the time of fabrication, 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. (Not shown).

The band-shaped member was made of the same material and processed as used in Production Example 1, and the lower cell was produced in Production Example 9.
The upper cell had the same layer configuration as that manufactured in Production Example 8, and the conditions for forming the deposited film of each semiconductor layer are shown in Table 10. The modularization process was performed by the same operation and method as in Production Example 8 to produce a solar cell module.

For the fabricated solar cell module, AM1.5 (100mW
/ cm ²⁾ was subjected to characteristic evaluation under optical irradiation, obtained over 10.3% in the photoelectric conversion efficiency had more variation in the characteristics among the modules accommodated 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 ² ) light for 500 hours was within 9%.

By connecting these modules, a 3 kW power supply system was made.

Production Example 12 In this production example, a photovoltaic device having a layer configuration shown in FIG. 11 (C) 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 gas gates. A device (not shown) was used.

Note that the band-shaped member used was the same material and processed as used in Production Example 1, and the lower cell was Production Example 8
The upper cell had the same layer configuration as that manufactured in Production Example 10, and the conditions for forming the deposited film of each semiconductor layer are shown in Table 11. The modularization process was performed by the same operation and method as in Production Example 8 to produce a solar cell module.

For the fabricated solar cell module, AM1.5 (100mW
/ cm ²⁾ was subjected to characteristic evaluation under optical irradiation, obtained over 10.2% in the photoelectric conversion efficiency had more variation in the characteristics among the modules accommodated 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 ² ) light for 500 hours was within 9%.

By connecting these modules, a 3 kW power supply system was made.

Production Example 13 In this production example, a photovoltaic element having a layer configuration shown in FIG. 11D was produced. In manufacturing, the isolation containers 300-a ', 300', 300-b ', 300-a ", 300", and 30 "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 O-b ″ was further connected in this order via a gas gate was used.

The band-shaped member was made of the same material and processed as used in Production Example 1, and the lower cell was produced in Production Example 9.
The intermediate cell has the same layer configuration as that of the production cell of Production Example 8, and the upper cell has the same layer constitution as that of the production cell of Production Example 10. The modularization process was performed by the same operation and method as in Production Example 8 to produce a solar cell module.

For the fabricated solar cell module, AM1.5 (100mW
/ cm ²⁾ was subjected to characteristic evaluation under optical irradiation, obtained over 10.4% in the photoelectric conversion efficiency had more variation in the characteristics among the modules accommodated within 5%.

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

By connecting these modules, a 3 kW power supply system was made.

[Summary of Effects of the Invention] 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 the width direction of the band-like member constituting the side wall of the film formation space, Microwave applicator means for emitting microwave energy in a direction parallel to the traveling direction of the wave,
By confining the deposition space with the microwave plasma, a large-area functional deposition film can be formed continuously and with good uniformity.

By confining the microwave plasma in the film forming space by the method and apparatus of the present invention, the stability and reproducibility of the microwave plasma are improved, and the utilization efficiency of the source gas for forming the deposited film is dramatically increased. Can be. Further, by continuously transporting the band-shaped member,
By changing the shape, length, and transfer speed of the curve in various ways, a deposited film having an arbitrary film thickness can be continuously deposited with good uniformity over a large area.

ADVANTAGE OF THE INVENTION According to the method and apparatus of this invention, a functional deposition film can be formed continuously and with good uniformity on the surface of a comparatively wide and long strip-shaped member. Therefore, it can be suitably used especially as a mass production machine for large area solar cells.

In addition, since a deposited film can be formed continuously without stopping discharge, good interface characteristics can be obtained when a stacked device or the like is manufactured.

In addition, it becomes possible to form a deposited film under a low pressure, suppress generation of polysilane powder, and suppress polymerization of active species, so that defects are reduced, film characteristics are improved, and film characteristics are stable. Improvement can be achieved.

Therefore, it is possible to improve the operation rate and the yield, and mass-produce inexpensive and highly efficient solar cells.

Further, the solar cell manufactured by the method and the apparatus of the present invention has high photoelectric conversion efficiency and has less 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. 3 to 5 are general schematic views of one example of the continuous microwave plasma CVD apparatus of the present invention. FIG. 6 is a schematic sectional view for explaining the mounting angle of the rectangular waveguide in the present invention. FIG. 7 is a schematic cross-sectional view of a Schottky junction diode manufactured in the present invention. FIGS. 8A to 8D are schematic cross-sectional views of a pin-type photovoltaic device (single, tandem, triple) manufactured in the present invention. FIGS. 9 (i) to 9 (X) are views for explaining a method of processing a belt-shaped member. FIG. 10 is a diagram schematically showing a pressure gradient of the gas gate means in the present invention. 1 to 9, 101... A belt-shaped member, 102, 103.
5 ... Conveying ring, 106a-e ... Temperature control mechanism, 107,1
08 …… Microwave applicator, 109,110 …… Microwave permeable member, 111,112 …… Square waveguide, 113 …… Gas introduction pipe, 114 …… Exhaust pipe, 115a, b …… Isolation passage, 116 ……
Deposition chamber, 200 ... Microwave applicator, 201,202 ...
... Microwave transmitting member, 203a, b ... Microwave matching disk, 204 ... Inner cylinder, 205 ... Outer cylinder, 206 ... Fixing ring, 207 ... Chalk flange, 208 ... Square waveguide Tube, 20
9 ... cooling medium, 210 ... O-ring, 211 ... groove, 212 ...
Metal seal, 213, 214… Cooling air inlet / outlet, 30
1,302,501,502… Vacuum container, 303… Delivery bobbin, 304… Winding bobbin, 305, 306… Transport roller, 307, 308, 309… Throttle valve, 310, 311, 31
8,319,320 …… Exhaust hole, 312,313 …… Temperature adjustment mechanism, 314,
315… Pressure gauge, 316,317,405,406,407,408 …… Gate gas inlet pipe, 321,322,401,402,403,404 …… Gas gate, 4
09,410,411,412… Gate gas exhaust pipe, 503,504… Cathode electrode, 505,506… Gas inlet pipe, 507,508… Halogen lamp, 509,510… Anode electrode, 511,512… Exhaust pipe, 701,801… Support, 702,802 …… Lower electrode, 703,
803,808,814,817 ... n-type semiconductor layer, 704,804,809,815,8
18 i-type semiconductor layer, 705 metal layer, 706,707 ... current extraction terminal, 800,800 ', 811,812,820,821,823 p
in-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 photovoltaic element, 901a ...... Band-shaped member processing chamber (A), 901b ... Band-shaped member processing chamber (B), 902,903,904,905,906 ... Band-shaped member, 907
a, 907b …… Roller, 908a, 908b …… Cutting blade, 909a, 909b
…… Welding jig, 910,911,912,913 …… Connection means.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Toshimitsu Kariya 3- 30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Yasushi Fujioka 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inside (72) Inventor Tetsuya Takei 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (72) Inventor Hiroshi Echizen 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. ( 56) References JP-A-61-288074 (JP, A) JP-A-62-294181 (JP, A) JP-A-59-100516 (JP, A) JP-A-59-68925 (JP, A) Sho 61-263120 (JP, A) JP-A Sho 63-114973 (JP, A)

Claims (20)

(57) [Claims] 1. A column-shaped film-forming space having a side wall formed by the moving band-like member is formed in the middle of the belt-like member while moving the band-like member continuously in the longitudinal direction. At the same time, the microwave energy is radiated by microwave applicator means for radiating the microwave energy in a direction parallel to the traveling direction of the microwave. Microwave plasma CVD, wherein plasma is generated in the film-forming space, and a deposited film is formed on the surface of the continuously moving strip-shaped member constituting the side wall exposed to the microwave plasma. A method in which a large-area functional deposition film is continuously formed by a method. 2. In the middle of the moving band-shaped member, the band-shaped member is interposed between the curved start-end forming unit and the curved end-end forming unit using a curved start end forming unit and a curved end end forming unit. The method for continuously forming a large-area functional deposition film according to claim 1, wherein the band-shaped member is curved so as to form a side wall of the film-forming space while leaving a gap in a longitudinal direction of the 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 a columnar deposition 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. A large area functional deposition film according to claim 3, wherein said microwave applicator means is disposed perpendicular to said end face to radiate said microwave energy in a direction parallel to said side wall. Method to form the target. 5. A large area functional deposition film according to claim 1, wherein said microwave energy is radiated through a microwave transmitting member provided at a tip portion of said microwave applicator means. Method to form the target. 6. The large-area functional deposition film according to claim 5, wherein the microwave-permeable member keeps the microwave applicator means and the film-forming space airtight. How to form. 7. In a case where the microwave applicator means is disposed so as to face each other on the both end faces,
4. The method for continuously forming a large-area functional deposition film according to claim 3, wherein the arrangement is such that microwave energy emitted from one microwave applicator means is not received by the other microwave applicator means. 8. A large area functional deposition film according to claim 1, wherein microwave energy radiated into said columnar deposition space is prevented from leaking out of said deposition space. how to. 9. A gap left in the longitudinal direction of the belt-like 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. 10. The method according to claim 1, wherein a conductive treatment is performed on at least one surface of the strip-shaped member. 11. An apparatus for continuously forming a functional deposited film on a continuously moving strip member by a microwave plasma CVD method, wherein the strip member is continuously moved in a longitudinal direction thereof. 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 film formation A means for introducing a deposition film forming source gas into the chamber; and a temperature control means for heating and / or cooling the strip-shaped member, wherein the microwave plug of the strip-shaped member is provided. An apparatus for continuously forming a functional deposited film, wherein a deposited film is continuously formed on a surface on a side which is exposed to the zuma. 12. The curving portion forming means comprises at least one set of a curving start end forming means and a curving end forming means, wherein the curving start end forming means and the curving end forming means comprise: 12. The continuous functional deposition film forming apparatus according to claim 11, wherein the apparatus is disposed with a gap left in the longitudinal direction of the band-shaped member. 13. The curved portion forming means comprises at least a pair of supporting / transporting rollers and a supporting / transporting ring, wherein the pair of supporting / transporting rollers leave a gap in the longitudinal direction of the band-shaped member. Claims that are arranged in parallel
13. The apparatus for continuously forming a functional deposition film according to item 12. 14. The function according to claim 11, 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. 15. The continuous functional deposition film forming apparatus according to claim 14, wherein said microwave applicator means is disposed in a direction perpendicular to said end face. 16. An airtight separation between the film forming chamber and the microwave applicator means at a distal end portion of the microwave applicator means, and applying microwave energy radiated from the microwave applicator to the film applicator means. 12. The continuous functional deposition film forming apparatus according to claim 11, further comprising a microwave permeable member that allows transmission into a room. 17. The apparatus for continuously forming a functional deposition film according to claim 11, wherein at least one surface of the belt-shaped member is subjected to a conductive treatment. 18. An apparatus for continuously forming a functional deposited film according to claim 14, wherein microwave energy is transmitted to said microwave applicator means via a rectangular and / or elliptical waveguide. 19. When the microwave applicator means is disposed opposite to each other on 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. Comrades including sides,
19. The continuous functional deposition film forming apparatus according to claim 18, wherein the planes including the long axis or the plane including the long side and the plane including the long axis are arranged so as not to be parallel to each other. 20. An angle between a plane including a long side and / or 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 perpendicular to the plane. 20. The apparatus for continuously forming a functional deposition film according to claim 19, wherein the apparatus is arranged so as not to be disturbed.