JP2810529B2 - Method and apparatus for forming deposited film - Google Patents

Description

Description: TECHNICAL FIELD The present invention uses a novel microwave energy supply device capable of generating a uniform microwave plasma over a large area, and a plasma reaction caused by the new microwave energy supply device.
The present invention relates to a method and an apparatus for continuously forming a large-area composition-controlled functional deposition film by decomposing and exciting a source gas.

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 Prior 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,
Severe radioactive contamination, which is harmful to the human body and harms the natural environment, as typified by the accident at the Chernobyl nuclear power plant, threatened the future spread of nuclear power generation. Some countries have even 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.
In the advanced nations, coupled with the increase in power consumption per capita due to the further promotion of electronics in lifestyles, the problem of power supply must be considered on a global scale.

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 problems have been made toward its 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 electric power to 100,000 households, a solar cell having an area of 3,000,000 m ² is required.

For this reason, a gaseous source gas such as silane, which is easily available, is used, and this 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 doing so are attracting attention because they are rich in mass productivity and can be manufactured at a lower cost than solar cells manufactured using single crystal silicon, etc. Has been made.

In a power generation system using a solar cell, a format 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 and short-circuit do 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, is ensured at least at the stage of producing the unit module. From the viewpoint of facilitating the module design and simplifying the module assembly process, it is possible to provide a semiconductor deposition film having excellent characteristics uniformity over a large area, thereby increasing the mass productivity of solar cells. A significant reduction in production costs will be achieved.

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 its production, phosphine (PH ₃ ), diborane (B
A semiconductor film having a desired conductivity type is obtained by mixing a source gas containing an element serving as a dopant such as ₂ H ₆ ) with silane or the like as a main source gas and subjecting the mixture to glow discharge decomposition. It is known that a semiconductor junction can be easily achieved by sequentially laminating the semiconductor films. From this fact, it has been proposed to provide an independent film formation chamber for forming each semiconductor layer and to form each semiconductor layer in the film formation chamber for manufacturing an amorphous silicon solar cell. Have been.

By the way, U.S. Pat.
A continuous plasma CVD apparatus employing a roll-to-roll system is disclosed. According to this apparatus, a plurality of glow discharge regions are provided, and a sufficiently long flexible substrate having a desired width is arranged along a path through which the substrate sequentially passes through each of the glow discharge regions. It is stated that the element having a semiconductor junction can be continuously formed by continuously transporting the substrate in the longitudinal direction while depositing and forming a semiconductor layer of a conductivity type required in the discharge region. In this specification, a gas gate is used to prevent a dopant gas used for forming each semiconductor layer from diffusing and mixing into another glow discharge region. Specifically, 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 a flow of scavenging 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, a predetermined plasma is always generated over a large area and the plasma is uniformly maintained when a deposition process is performed on a substantially long substrate. There is a need to. 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 connecting 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.

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 the use of a slow-wave circuit, which has an abrupt microwave coupling to the plasma as the microwave applicator increases in lateral distance. It has a unique problem that a drop 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. 4,521,717 discloses such a method. In the former, it is described that the slow-wave circuit needs to be inclined at a certain angle with respect to the substrate, but the transmission efficiency of microwave energy to plasma is not satisfactory. Further, in the latter, it is disclosed that two slow wave circuits are provided in a plane parallel to the base body in a non-parallel manner. That is, it is desirable that the planes perpendicular to the center of the microwave applicator cross each other in a plane parallel to the substrate to be processed and on a straight line perpendicular to the moving direction of the substrate. In order to avoid interference between the two applicators, each of them is displaced laterally to the direction of movement of the substrate by half the length of the waveguide crossbar.

Some proposals have been made to maintain plasma uniformity (ie, energy uniformity). The proposals are, for example, from the Journal of Bakiyum Science Technology (Journal
of Vacuum Science Technology) B-4 (January 1986-
(Feb.) 295-298 and B-4 (January 1986-
(February) found in the report on pages 126-130. According to these reports, a microwave reactor called a microwave plasma disk source (MPDS) 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 a microwave plasma disk source designed to operate at 2.45 GHz, the confinement diameter of the plasma is no more than 10
cm, and the plasma volume is at most about 118 cm ³ , which cannot be said to be a large area at all. The report also states that in systems designed to operate at frequencies as low as 915 MHz, lower frequencies provide a plasma diameter of about 40 cm and a plasma volume of 2000 cm ³ . The report may further include a lower frequency, e.g.,
By operating at 400MHz, the discharge can be expanded to a diameter exceeding 1m. 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 volume 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.

Accordingly, there is a need for an early provision of a new microwave applicator that solves the various problems of the microwave means described above.

By the way, thin-film semiconductors have a large area or a long size, such as thin-film transistors (TFTs) for driving pixels of liquid crystal displays, photoelectric conversion elements for contact-type image sensors, and switching elements, in addition to the above-mentioned applications for solar cells. 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.

It is another object of the present invention to provide a method and an apparatus for forming a functional deposition film having a chemical composition that changes continuously in the longitudinal direction from a continuously moving strip 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.

Yet another object of the present invention is to provide a microwave applicator that can generate 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.

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

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

[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 research to achieve the object of the present invention. A state in which microwave applicator means for emitting or transmitting with directivity in one vertical direction is included in a microwave transmitting member, and the inner peripheral wall of the microwave applicator means is not in contact with the microwave applicator means. When a microwave is supplied from a microwave power supply to the microwave applicator means, a raw material gas for forming a deposited film is introduced into the film formation chamber, and a predetermined pressure is maintained. It has been found that uniform microwave plasma can be generated in the longitudinal direction of the applicator means in the film forming chamber.

The present invention has been completed as a result of further studies based on the above-mentioned findings, and it is to form a large-area functional deposited film continuously by a microwave plasma CVD method which is based on the following. Methods and apparatus.

The method of the present invention is as follows. That is, the band-shaped member is moved in the longitudinal direction, and a film-forming space having a side wall on the band-shaped member is formed on the way, and at least two or more kinds of deposited films having different compositions are formed in the formed film-forming space. Microwave applicator means for separately introducing each of the source gases through a plurality of gas supply means and simultaneously radiating or transmitting microwave energy uniformly in one direction perpendicular to the direction in which the microwaves travel. Thereby, the microwave energy is radiated or transmitted toward the band-shaped member in the film forming space to generate microwave plasma in the film forming space, and constitutes the side wall exposed to the microwave plasma. A method for forming a deposited film by a microwave plasma CVD method, wherein a deposited film is formed on the belt-shaped member.

In the method of the present invention, the moving strip-shaped member
On the way, using the curved start end forming means and the curved end end forming means, the band-shaped member is left with a gap in the longitudinal direction of the band-shaped member between the curved start end forming means and the curved end end forming means. The member is curved to form a side wall of the film forming space.

Then, microwave energy may be radiated or transmitted into the film forming space from a gap left in the longitudinal direction of the band-shaped member between the bending start end forming unit and the bending end end forming unit. Alternatively, the microwave energy is applied to the film forming space by projecting the microwave applicator means into the film forming space from one of both end surfaces of a columnar film forming space formed with the band-shaped member as a side wall. You may make it radiate | transmit or transmit in space.

The microwave energy radiated or transmitted from the microwave applicator means is radiated or transmitted into the film deposition space via a microwave permeable member provided between the film deposition space and the applicator means. To

In a range not to contact the microwave permeable member,
The microwave applicator means is disposed close to and substantially parallel to the width direction of the band-shaped member so as to radiate or transmit microwave energy into the columnar deposition space.

The microwave applicator radiates or transmits microwave energy uniformly to a length substantially equal to the width direction of the band-shaped member.

The microwave applicator means is separated from the microwave plasma generated in the film forming space via the microwave permeable member.

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

In the method of the present invention, each of the gas supply means is disposed in parallel with a width direction of a band-shaped member constituting the side wall, and the deposited film forming raw material gas is discharged in one direction toward the adjacent band-shaped member. To do.

Further, the apparatus of the present invention is a deposition film forming apparatus for moving a belt-shaped member in the longitudinal direction and forming a deposited film on the belt-shaped member in the middle thereof, wherein the deposition-film forming apparatus moves the belt-shaped member in the longitudinal direction to support the belt-shaped member. The belt-like member is provided as a wall functioning as a wall provided with a set of rollers arranged in parallel with each other with a predetermined space between them in the longitudinal direction from the feeding mechanism to the winding mechanism. Film-forming space forming means for supporting the band-shaped member to form a film space; and the band-shaped member arranged in the film-forming space with directivity in one direction perpendicular to the direction in which microwaves travel. Microwave applicator means connected to the film formation space to generate microwave plasma in the film formation space by uniformly introducing microwave energy toward the film formation space, and generating the microwave plasma in the film formation space. My A separating unit for separating the applicator unit from the microwave plasma, an exhaust unit for exhausting the inside of the film forming space, and at least two or more for introducing a deposition film forming material gas into the film forming space. An apparatus for forming a deposited film, comprising: gas supply means; and temperature control means for heating or cooling the belt-shaped member.

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 according to the aspect of the invention, the separation unit may be disposed substantially parallel to a gap left between the bending start end forming unit and the bending end end forming unit, and may be disposed outside the film forming chamber. Alternatively, one of the two end surfaces of the columnar film forming chamber formed with the band-shaped member as a side wall may protrude into the film forming chamber substantially in parallel with the width direction of the band-shaped member. .

The separating means may be substantially cylindrical or substantially semi-cylindrical.

On the other hand, the microwave applicator means is disposed so as to be separated from the peripheral wall of the separation means and included in the inside of the separation means.

In the apparatus of the present invention, the separating means is provided with a cooling means, and the cooling means is an air flow flowing along an inner peripheral surface of the separating means.

Further, the cooling means may be configured concentrically with the separating means so as to have a conduit structure provided inside the separating means and capable of flowing a cooling medium between the separating means.

In the apparatus of the present invention, the microwave applicator means is a microwave transmission waveguide, and the microwave energy is applied to the film forming chamber substantially uniformly in a longitudinal direction of the microwave application direction. A substantially rectangular hole is provided for directing radiation in one direction perpendicular to.

In addition, at least one or more rectangular holes are formed on one surface of the waveguide, and microwaves are radiated from the holes.

When a plurality of rectangular holes are formed, these holes are arranged at intervals in the longitudinal direction of the waveguide.

In addition, the rectangular hole may be a single rectangular having a large aspect ratio, the size of which is greater than one wavelength of microwave and substantially the entire width and the longitudinal direction of the rectangular waveguide. Approximately equal in length.

Then, microwave energy is uniformly radiated from the rectangular hole in a length direction of at least one wavelength of the radiated microwave in the longitudinal direction of the waveguide.

Shutter means are provided in the square hole to ensure that microwave energy is emitted from the square hole at substantially uniform density over the entire length of the microwave applicator.

In the apparatus of the present invention, the microwave plasma is confined in a column-shaped film forming chamber formed by bending the band-shaped member.

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

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

Further, the microwave energy of the present invention may be evanescent microwave energy.

In the apparatus of the present invention, the microwave applicator means is an elongated slow-wave circuit waveguide, and the slow-wave circuit waveguide introduces evanescent microwave energy substantially uniformly in the longitudinal direction into the film forming chamber. It has a ladder-like structure for transmitting.

The length of the ladder-like structure is substantially equal to the length of the band-shaped member in the width direction.

The ladder-like structure has a structure in which evanescent microwave energy is transmitted uniformly over at least one wavelength of the microwave transmitted in the longitudinal direction.

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

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

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

[Experiment]

Using the apparatus of the present invention, in order to examine the generation conditions of microwave plasma and the relative positional relationship between the strip-shaped member and the separating means for uniformly forming a functional deposition film on the strip-shaped member, The experiments described were performed.

Experimental Examples 1 to 9 In the apparatus having the configuration shown in the apparatus example 1, the transfer ring was used.
The side of 104, 105 is an exhaust hole, connected to an exhaust pump (not shown), using various waveguides and microwave applicator means of hole processing dimensions shown in Table 1, and the microwave shown in Table 2 Experiments and evaluations were performed on plasma stability and the like under plasma discharge conditions. Table 3 shows the evaluation results.
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 Examples 10 to 18 In the apparatus having the structure shown in the apparatus example 5, the arrangement of the band-shaped member and the microwave applicator was arranged as shown in FIG. 5 (b), and the various waveguides shown in Table 1 were used. Experiments and evaluations were performed on the stability of plasma and the like using a microwave applicator having a tube and hole processing dimensions and under microwave plasma discharge conditions shown in Table 4.

Table 5 shows the evaluation results. 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 Examples 19 to 28 In the apparatus having the configuration shown in the apparatus example 3, the transfer ring was used.
The exhaust holes 104 and 105 are connected to an exhaust pump (not shown), and various waveguides and holes shown in Table 6 and those having a processing size of the shutter are used. The microwave plasma shown in Table 2 is used. Experiments on plasma stability under discharge conditions,
An evaluation was performed. Table 7 shows the evaluation results. In addition, in this discharge experiment, when the belt-shaped member 101 was stationary and when the belt-shaped member 101 was transported at a transport speed of 1.2 m / min, no particular difference was observed in the discharge stability between the two. .

EXPERIMENTAL EXAMPLES 29-38 In the apparatus having the construction shown in Apparatus Example 7, various waveguides, holes, and microwave processing applicators having a shutter processing dimension shown in Table 6 were used, and microwave plasma shown in Table 4 was used. Experiments and evaluations were performed on plasma stability and the like under discharge conditions. Table 8 shows the evaluation results. In addition,
In this discharge experiment, a test was performed when the belt-shaped member was stationary and when the belt was transported at a transport speed of 1.2 m / min, but no particular difference was observed in the discharge stability between the two.

Comparative Experimental Examples 1 to 4 In Experimental Examples 2, 7, 21 and 25, among the microwave plasma discharge conditions shown in Table 2, other conditions were not changed and only the pressure was variously changed as shown in Table 9. Then, the state of the plasma at that time was evaluated from the viewpoint of stability, uniformity, and the like. Regarding the evaluation, ◎ indicates the case where the most stable state was obtained, や indicates that there was no practical problem although the stability was somewhat poor, and △ indicates that there was a practical problem due to lack of stability and uniformity.
In the case where no discharge was performed or abnormal discharge or the like was present and it was not practical, the results were ranked as x, and the evaluation results are shown in Table 9.

As can be seen from these, it is understood that stable and uniform microwave plasma is formed in a relatively wide pressure range.

It should be noted that there was no particular change in these results even when the belt-shaped member was stationary or when the belt-shaped member was transported at a transport speed of 1.5 m / min.

Comparative Experimental Examples 5 to 8 In Experimental Examples 2, 7, 21, and 25, of the microwave plasma discharge conditions shown in Table 2,
By changing only the microwave power as shown in the table,
The state of the plasma at that time was evaluated from the viewpoints of stability, uniformity, etc., ◎ when the most stable state was obtained, ○ when the stability was somewhat lacking, but there was no practical problem,
Stability and lack of uniformity and a problem in practical use are rated as △, and no discharge or abnormal discharge etc. are impractical and are ranked as × .The evaluation results are shown in Table 10. Indicated.

As can be seen from these, it is understood that stable and uniform microwave plasma is formed in a relatively wide microwave power range.

It should be noted that there was no particular change in these results even when the belt-shaped member was stationary or when the belt-shaped member was transported at a transport speed of 1.5 m / min.

Comparative Experimental Examples 9 to 12 In Experimental Examples 2, 7, 21 and 25, among the microwave plasma discharge conditions shown in Table 2, other conditions were not changed and only L ₁ and L ₂ were used as shown in Table 11. Is changed in various ways, and the state of the plasma at that time is evaluated from the viewpoint of stability, uniformity, etc., and the case where the most stable state is obtained is ◎, slightly unstable, although there is no practical problem although it lacks uniformity. The case was rated as 、, the stability and uniformity were not practical due to lack of uniformity, and the case where there was no discharge or abnormal discharge, etc. was impractical and ranked as ×. The results of the evaluation are shown.

As can be seen from these, when at least one of L ₁ and L ₂ is larger than 1/4 wavelength of the microwave, microwave plasma flickers or microwave leakage increases, It can be seen that when the wavelength is four wavelengths or less, a stable and uniform microwave plasma is formed.

It should be noted that there was no particular change in these results even when the belt-shaped member was stationary or when the belt-shaped member was transported at a transport speed of 1.5 m / min.

Comparative Experimental Examples 13 to 16 In Experimental Examples 2, 7, 21 and 25, of the microwave plasma discharge conditions shown in Table 2, the other conditions were used without changing other conditions.
Only L ₃ as shown in Table while varying, when the stability conditions of the plasma to the, and evaluated in terms of such uniformity, the most stable and if the state has been obtained ◎, somewhat stability, uniformity If there is no practical problem but lacks, there is a rating of ○, if there is a practical problem with lack of stability and uniformity, and if it is not practical due to no discharge or abnormal discharge, etc. Table 12 shows the evaluation results.

As can be seen, L ₃ is 1/1 of the wavelength of the microwave.
It can be seen that the discharge becomes unstable at two wavelengths or less, but that stable and uniform microwave plasma is formed at half wavelength or more.

However, when L ₁ and L ₂ were larger than / 4 wavelength and L ₃ was too large, microwave leakage was large and discharge was unstable.

It should be noted that there was no particular change in these results even when the belt-shaped member was stationary or when the belt-shaped member was transported at a transport speed of 1.5 m / min.

Comparative Experimental Examples 17 to 20 In Experimental Examples 2, 7, 21, and 25, of the microwave plasma discharge conditions shown in Table 2,
As shown in the table, only the inner diameter of the curved shape was changed variously, and the state of the plasma at that time was evaluated from the viewpoint of stability, uniformity, etc., and when the most stable state was obtained, ◎, somewhat stable , A case where there is no practical problem with lack of uniformity, a case where there is a practical problem with lack of uniformity, and a case where it is not practical due to no discharge or abnormal discharge etc. The results were ranked and the evaluation results are shown in Table 13.

As can be seen from these, it is understood that uniform microwave plasma is formed stably up to a relatively large inner diameter.

It should be noted that there was no particular change in these results even when the belt-shaped member was stationary or when the belt was conveyed at a conveyance speed of 1.5 m / min.

Comparative Experimental Examples 21 to 24 In Experimental Examples 11, 18, 30, and 37, among the microwave plasma discharge conditions shown in Table 4, the other conditions were the same.
As shown in the table, only the pressure was variously changed, and the state of the plasma at that time was evaluated from the viewpoint of stability, uniformity, etc., and the case where the most stable state was obtained was evaluated as ◎, somewhat stable, uniformity Rank a case where there is no practical problem with lacking, 、, a case where there is a practical problem with lack of stability and uniformity, and a case where it is impractical due to no discharge or abnormal discharge etc. Table 14 shows the evaluation results.

As can be seen from these, it is understood that stable and uniform microwave plasma is formed in a relatively wide pressure range.

It should be noted that there was no particular change in these results even when the belt-shaped member was stationary or when the belt-shaped member was transported at a transport speed of 1.5 m / min.

Comparative Experimental Examples 25 to 28 In Experimental Examples 11, 18, 30, and 37, among the microwave plasma discharge conditions shown in Table 4, the other conditions were the same.
By changing only the microwave power as shown in the table,
The state of the plasma at that time was evaluated from the viewpoints of stability, uniformity, etc., ◎ when the most stable state was obtained, ○ when the stability was somewhat lacking, but there was no practical problem,
Stability, lack of uniformity and a problem in practical use are rated as △, and no discharge or no practical use due to the above discharge etc. are ranked as ×, and those evaluation results are shown in Table 15. Indicated.

As can be seen from these, it is understood that stable and uniform microwave plasma is formed in a relatively wide microwave power range.

It should be noted that there was no particular change in these results even when the belt-shaped member was stationary or when the belt-shaped member was transported at a transport speed of 1.5 m / min.

Comparative Experimental Examples 29 to 32 In Experimental Examples 11, 18, 30, and 37, among the microwave plasma discharge conditions shown in Table 4, the other conditions were not changed.
As shown in the table, only L ₄ was changed variously, and the state of the plasma at that time was evaluated from the viewpoint of stability, uniformity, etc., and the case where the state was most stably obtained was ◎, somewhat stable, A case where there is no practical problem with lack of uniformity is indicated by 、, a case where there is a practical problem with lack of stability and uniformity is indicated by △, and a case where impractical due to no discharge or abnormal discharge etc. is indicated by × The results were ranked and the evaluation results are shown in Table 16.

As can be seen from these, L ₄ is stable in almost half wavelength or less in the range of wavelength of the microwave, it can be seen that uniform microwave plasma is formed.

It should be noted that there was no particular change in these results even when the belt-shaped member was stationary or when the belt-shaped member was transported at a transport speed of 1.5 m / min.

Comparative Experimental Examples 33 to 36 In Experimental Examples 11, 18, 30, and 37, among the microwave plasma discharge conditions shown in Table 4, other conditions were not changed.
As shown in the table, only the inner diameter of the curved shape was changed variously, and the state of the plasma at that time was evaluated from the viewpoint of stability, uniformity, etc.を, when there is no practical problem with lack of uniformity, △, when there is a practical problem with lack of stability and uniformity,
Cases in which no discharge was performed or abnormal discharge or the like was impractical due to abnormal discharge were ranked as x, and the evaluation results are shown in Table 17.

As can be seen from these, it is understood that a stable and uniform microwave plasma is formed in a range where the inner diameter is up to about five times the diameter of the separation means.

It should be noted that there was no particular change in these results even when the belt-shaped member was stationary or when the belt-shaped member was transported at a transport speed of 1.5 m / min.

Comparative Experimental Examples 37 to 40 In Experimental Examples 1 and 37, except that the punching board for confining the microwave region was changed to one obtained by spraying alumina on the surface of a SUS316L thin plate, the other discharge conditions were not changed, and the plasma was not changed. When the same evaluation was performed for the stability and the like, no particular difference was found in any case.

Outline of Experimental Results In the method and apparatus of the present invention, the stability and uniformity of the microwave plasma are determined by, for example, the type and shape of the microwave applicator, the pressure in the deposition chamber during deposition, the microwave power, and the microwave plasma. Since various parameters such as the degree of confinement, the volume and the shape of the discharge space are intricately entangled, it is difficult to find the optimum conditions with only a single parameter.
The following trends and condition ranges were found.

Regarding pressure, preferably 1-3 mTorr to 200-500
Torr, more preferably 3-10 mTorr to 100-200 mTorr. Regarding microwave power, preferably 300-700W to 3000-5000W, more preferably 300-7W
It turned out that it was 00W-1500-3000W. Further, the inner diameter of the curved shape is almost stable by being set to preferably about 5 times, more preferably about 4 times the length of the outer peripheral wall of the separation means exposed to the microwave plasma region. As a result, it was found that uniform microwave plasma was maintained.

Also, it has been found that when the amount of microwave energy leaking from the microwave plasma region increases, the stability of the plasma is lacking, and the gap formed by either the curved end of the belt-shaped member or the separating means is preferably 1 μm of the microwave. It has been found that it is desirable to set the wavelength to not more than / 2 wavelength, more preferably not more than 1/4 wavelength.

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 walls of the columnar film-forming space formed by bending the band-shaped member using the curved start end forming unit and the curved end-end forming unit in the middle of the moving band-shaped member. The moving belt-shaped member is formed, 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 band-shaped member.

In the method of the present invention, in order to uniformly generate microwave plasma in the columnar deposition space, microwave applicator means capable of uniformly radiating or transmitting microwave energy in the width direction of the band-shaped member. From either one of both end surfaces in the columnar film-forming space, in a direction substantially parallel to the width direction of the band-shaped member, or between the bending start end forming means and the bending end end forming means. It is desirable to dispose in close proximity almost parallel to the gap left in the longitudinal direction. From the microwave applicator means, microwave energy is radiated or transmitted with directivity in one direction perpendicular to the traveling direction of the microwave, but in any case, the columnar film forming space The microwave energy radiated or transmitted into the inside is reflected and scattered by the band-like member constituting the side wall, uniformly fills the film forming space, and is simultaneously introduced by the gas supply means. Since the gas is efficiently absorbed, uniform microwave plasma can be formed.

However, in order to stably generate the microwave plasma with good reproducibility, the microwave energy is efficiently radiated or transmitted into the film formation space, and the microwave energy leaks from the film formation space. Care must be taken to prevent the occurrence of

For example, in the former case, a gap left in the longitudinal direction of the band-shaped member between one end face of the applicator unit that is not protruded and the curved start end forming unit and the curved end end forming unit of the band-shaped member. It is necessary to prevent leakage of microwave energy from the like, and the end face and the gap are sealed with a conductive member, or the hole diameter is preferably 1/2 wavelength or less of the wavelength of microwave used. It is preferable to cover the wire with a wire mesh having less than 1/4 wavelength or a punching board.

When projecting the microwave applicator means into the film forming space, it is desirable that the microwave applicator means be disposed at a position substantially equidistant from the side wall, but when the curved shape of the side wall is asymmetric, etc. Is not particularly limited.

In the latter case, the direction in which the microwave energy is radiated or transmitted from the microwave applicator means with directivity is left between the bending start end forming means and the bending end end forming means of the band-shaped member. It must be suitable for the gap. Then, in order to efficiently radiate or transmit the microwave energy into the columnar deposition space, the longitudinal direction of the band-shaped member in the gap left between the curved start end forming means and the curved end end forming means The minimum dimension of the opening width is preferably 1/4 wavelength or more, more preferably 1/2 wavelength or more of the microwave wavelength.

If the gap and the interval between the microwave applicator means are too large, the amount of microwave energy radiated or transmitted into the film formation space decreases, and the radiated or transmitted microwave energy is reduced. There is a case where the confinement of wave energy becomes insufficient.

However, the radiation or transmission direction of the microwave energy and the opening width, and the interval between the gap and the microwave applicator are important in efficiently supplying the microwave energy into the columnar deposition space. Although it has a meaning but is mutually related, it is preferable to appropriately adjust and arrange so as to maximize the efficiency.

In addition, from both end surfaces of the columnar film-forming space, it is sealed with a conductive member so that microwaves do not leak, or the hole diameter is preferably 1/2 wavelength or less of the wavelength of microwave used, more preferably 1 or less. It is desirable to cover with a wire mesh of / 4 wavelength or less, a punching board or the like.

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

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

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 pressure in the film forming space is such that the microwave plasma is uniformly generated. , But there is no particular limitation on the direction in which the gas is exhausted. However, in the exhaust hole, it is necessary to take care that the microwave does not leak from the location and the source gas is efficiently exhausted. Of course, when the source gas is exhausted from the plurality of exhaust holes, it is preferable to make the gas diffusion, flow type, and the like in the film forming space substantially uniform. It may be restricted.

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

The gas supply means is arranged in parallel with the belt-like member constituting the side wall.

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

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

Examples of the composition-controlled functional deposition film formed by the method of the present invention include SiGe, SiC, GeC, SiSn, GeSn, and SnC.
Group IV alloy semiconductor thin film, so-called II such as GaAs, GaP, GaSb, InP, InAs
Group IV compound semiconductor thin film, ZnSe, ZnS, ZnTe, CdS, CdSe, CdTe
So-called II-VI compound semiconductor thin film, CuAlS ₂ , CuAlSe ₂ , CuAl
Te ₂ , CuInS ₂ , CuInSe ₂ , CuInTe ₂ , CuGaS ₂ , CuGaSe ₂ , CuGaTe, A
gInSe ₂ , AgInTe ₂ etc. so-called I-III-VI compound semiconductor thin film, Zn
So-called II-IV-V compound semiconductor thin film such as SiP ₂ , ZnGeAs ₂ , CdSiAs ₂ , CdSnP ₂ , Cu ₂ O, TiO ₂ , In ₂ O ₃ , SnO ₂ , ZnO, CdO, Bi ₂ O ₃ , CdSnO
₄ Hitoshisho called oxide semiconductor thin film, and may be mentioned those which contains a valence electron controlling element to valence electron control these semiconductor. Further, there may be mentioned a material in which a valence electron controlling element is contained in a so-called group IV semiconductor thin film such as Si, Ge and C. Of course, amorphous semiconductors such as a-Si: H and a-Si: H: F may have different contents of hydrogen and / or fluorine.

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

That is, by changing the forbidden band width and / or the valence electron density in the vertical direction of the deposited semiconductor layer, the carrier traveling property is enhanced, and the carrier recombination at the semiconductor interface is prevented, so that the electrical characteristics are improved. Is improved. In addition, by continuously changing the refractive index to form an optically non-reflective surface, the light transmittance into the semiconductor layer can be improved. Further, by changing the hydrogen content or the like, a structural change is applied to alleviate stress, so that a deposited film having high adhesion to a substrate can be formed.

Further, by forming semiconductor layers having different crystallinities in the lateral direction, for example, a photoelectric conversion element formed of an amorphous semiconductor and a switching element formed of a crystalline semiconductor are simultaneously formed continuously on the same substrate. I can do it.

In the present invention, the deposition film forming source gas used for forming the above-mentioned functional deposition film is appropriately adjusted in its mixing ratio in accordance with the structure of the desired functional deposition film, and is used in the deposition space. To be introduced. A plurality of gas supply means are used for the introduction, but the composition of the deposited film forming source gas introduced from each gas supply means may be different, or may be the same depending on the purpose. Further, the composition may be changed continuously over time.

In order to form a group IV semiconductor or a group IV alloy semiconductor thin film in the present invention, preferably used, as the compound containing a group IV element of the periodic table, Si atom, Ge atom, C atom, Sn atom, Pb atom Compounds, specifically, SiH ₄ , Si
_{2 H 6, Si 3 H 8} , Si 3 H 6, Si 4 H 8, Si 5 H silane compounds such as _{10, SiF 4, (SiF 2} ) 5, (SiF 2) 6, (SiF 2) 4, Si ₂ F ₆ , Si
_{3 F 8, SiHF 3, SiH} 2 F 2, Si 2 H 2 F 4, Si 2 H 3 F 3, SiCl 4, (SiCl
_{2) 5, SiBr 4, (} SiBr 2) 5, Si 2 Cl 6, Si 2 Br 6, SiHCl 3, SiHB
_{r 3, SiHI 3, Si 2} Cl halogenated silane compounds such as ₃ F _3, GeH
_4, Ge ₂ H germane compounds such as _{6, GeF 4, (GeF 2} ) 5, (Ge
F ₂ ) ₆ , (GeF ₂ ) ₄ , Ge ₂ F ₆ , Ge ₃ F ₈ , GeHF ₃ , GeH ₂ F ₂ , Ge ₂ H ₂ F
_{4, Ge 2 H 3 F 3} , GeCl 4, (GeCl 2) 5, GeBr 4, (GeBr 2) 5, Ge 2 C
l ₆ , Ge ₂ Br ₆ , GeHCl ₃ , GeHBr ₃ , GeHI ₃ , germanium halide compounds such as Ge ₂ Cl ₃ F ₃ , CH ₄ , C ₂ H ₆ , methane series hydrocarbon gas such as C ₃ H ₈ , Ethylene hydrocarbon gas such as C ₂ H ₄ and C ₃ H ₆ , cyclic hydrocarbon gas such as C ₆ H ₆ , CF ₄ , (CF ₂ ) ₅ , (CF
₂ ) ₆ , (CF ₂ ) ₄ , C ₂ F ₆ , C ₃ F ₈ , CHF ₃ , CH ₂ F ₂ , CCl ₄ , (CCl ₂ )
_{5, CBr 4, (CBr 2} ) 5, C 2 Cl 6, C 2 Br 6, CHCl 3, CHI 3, C 2 Cl 3
Halogenated carbon compounds such as _{F 3, SnH 4, Sn (} CH 3) tin compounds such as _{4, Pb (CH 3) 4} , Pb (C 2 H 5) Lead compounds such ₆ and the like. These compounds may be used alone or in combination of two or more.

In the present invention, desired composition control is performed by appropriately mixing and using these compounds.

Group IV semiconductors formed in the present invention, or as a valence electron controlling agent used for controlling the valence electrons of the group IV alloy semiconductor, as a p-type impurity, a group III element of the periodic table, for example, B, Al, Ca, In, Tl and the like are mentioned as preferable ones, and as the n-type impurity, elements of the group V of the periodic table, for example, N, P, As, Sb and Bi are preferably mentioned. Particularly, B, Ga, P, Sb and the like are most suitable. The amount of the impurity to be doped is appropriately determined according to desired electrical and optical characteristics.

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

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

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

As the valence electron controlling agent used for controlling the valence electrons of the II-VI group compound semiconductor formed in the present invention, compounds containing elements of the periodic table I, III, IV, V group and the like are effective. Can be mentioned.

Specifically, compounds containing a Group I element include LiC ₃ H ₇ ,
Preferred examples include Li (sec-C ₄ H ₉ ), Li ₂ S, and Li ₃ N.

Compounds containing Group III elements include BX ₃ , B ₂ H ₆ ,
_{B 4 H 10, B 5 H} 9, B 5 H 11, B 6 H 10, B (CH 3) 3, B (C 2 H 5) 3, B 6 H
_{12, AlX 3, Al (CH} 3) 2 Cl, Al (CH 3) 3, Al (OCH 3) 3, Al (CH 3)
_{Cl 2, Al (C 2 H} 5) 3, Al (OC 2 H 5) 3, Al (CH 3) 3 Cl 3, Al (iC
_{4 H 9) 3, Al (} iC 3 H 7) 3, Al (C 3 H 7) 3, Al (OC 4 H 9) 3, GaX 3, G
a (OCH ₃ ) ₃ , Ga (OC ₂ H ₅ ) ₃ , Ga (OC ₃ H ₇ ) ₃ , Ga (OC ₄ H ₉ ) ₃ , Ga (C
_{H 3) 3, Ga 2 H} 6, GaH (C 2 H 5) 2, Ga (OC 2 H 5) (C 2 H 5) 2, In (CH 3)
₃ , In (C ₄ H ₉ ) ₃ , and compounds containing group V elements include NH ₃ , H
_{N 3, N 2 H 5 N} 3, N 2 H 4, NH 4 N 3, PX 3, P (OCH 3) 3, P (OC
_{2 H 5) 3, P (} C 3 H 7) 3, P (OC 4 H 9) 3, P (CH 3) 3, P (C 2 H 5) 3, P (C
_{3 H 7) 3, P (} C 4 H 9) 3, P (OCH 3) 3, P (OC 2 H 5) 3, P (OC 3 H 7) 3, P
(OC ₄ H ₉ ) ₃ , P (SCN) ₃ , P ₂ H ₄ , PH ₃ , AsH ₃ , AsX ₃ , As (OCH ₃ )
_{3, As (OC 2 H 5} ) 3, As (OC 3 H 7) 3, As (OC 4 H 9) 3, As (CH 3) 3, A
s (CH ₃ ) ₃ , As (C ₂ H ₅ ) ₃ , As (C ₆ H ₃ ) ₃ , SbX ₃ , Sb (OC ₂ H ₅ ) ₃ , S
b (OC ₃ H ₇ ) ₃ , Sb (OC ₄ H ₉ ) ₃ , Sb (CH ₃ ) ₃ , Sb (CH ₃ ) ₃ , Sb (C
₃ H ₇ ) ₃ and Sb (C ₄ H ₉ ) ₃ .

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

Of course, these raw materials may be of one kind,
Species or more may be used in combination.

Further, as the compound containing a group IV element, the compounds described above can be used.

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

As the valence electron controlling agent used for controlling the valence electrons of the group III-V compound semiconductor formed in the present invention, compounds containing elements of the periodic table II, IV, VI group and the like are mentioned as effective ones. Can be.

Specifically, as a compound containing a group II element, Zn (C
_{H 3) 2, Zn (C} 2 H 5) 2, Zn (OCH 3) 2, Zn (OC 2 H 5) 2, Cd (CH 3) 2,
Cd (C ₂ H ₅ ) ₂ , Cd (C ₃ H ₇ ) ₂ , Cd (C ₄ H ₉ ) ₂ , Hg (CH ₃ ) ₂ , Hg (C
₂ H ₅ ) ₂ , Hg (C ₆ H ₅ ) ₂ , Hg [C = (C ₆ H ₅ )] ₂ and the like.Examples of compounds containing a Group VI element include NO, N ₂ O, C
_{O 2, CO, H 2 S} , SCl 2, S 2 Cl 2, SOCl 2, SeH 2, SeCl 2, Se 2 B
r ₂ , Se (CH ₃ ) ₂ , Se (C ₂ H ₅ ) ₂ , TeH ₂ , Te (CH ₃ ) ₂ , Te (C ₂ H ₅ ) ₂
And the like.

Of course, these raw materials may be of one kind,
Species or more may be used in combination.

Further, examples of the compound containing a Group VI element include the compounds described above.

The raw material compounds described above in the present invention are He, Ne, Ar, K
It may be introduced as a mixture with a rare gas such as r, Xe, and Rn, and a diluent gas such as H ₂ , HF, and HCl.

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

In the method of the present invention, in order to uniformly and stably generate and maintain the microwave plasma in the columnar film forming space, the shape and volume of the film forming space, the source gas introduced into the film forming space, Although there are optimal conditions for the type and flow rate, the pressure in the film formation space, the amount of microwave energy radiated or transmitted into the film formation space, and the matching of microwaves, these parameters are mutually It is organically connected and is not defined unconditionally, and it is desirable to set preferable conditions as appropriate.

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 side wall of the film-forming space is formed. By providing the microwave applicator means for radiating or transmitting the microwave energy uniformly in the width direction of the belt-shaped member, a large-area functional deposition film can be formed continuously and with good uniformity. .

The point that the method of the present invention is objectively distinguished from the conventional method of forming a deposited film is that the deposition space is formed in a columnar shape, the sidewall thereof continuously moves, and functions as a structural material. The point is that it also serves as a support for formation.

Here, the function as a structural material is, in particular, a function of physically and scientifically isolating an atmosphere space for film formation, that is, a film formation space and an atmosphere space not involved in film formation. This means, for example, the function of forming different atmospheres in the gas composition and the state thereof, limiting the flow direction of the gas, and forming the atmospheres having different pressure differences.

That is, in the method of the present invention, the band-shaped member is curved to form a side wall of a columnar film-forming space, and any of the other remaining wall surfaces, that is, both end faces and a gap left on a part of the side wall are used. By supplying a source gas for forming a deposited film and microwave energy from the location to the inside of the film formation space and exhausting the same, microwave plasma is confined in the film formation space and the side wall is formed. A functional deposition film is formed on the band-shaped member, and the band-shaped member itself plays an important function as a structural material for isolating the film-forming space from an external atmosphere space not involved in film-forming. It can also be used as a support for forming a deposited film.

Therefore, the external atmosphere of the film formation space configured with the band-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 support for forming a deposited film is disposed in a film forming space for forming a deposited film, and is exclusively formed in the film forming space. It functions only as a member on which the precursor of the above 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 methods such as RF plasma CVD and sputtering, the substrate or the support for forming the deposited film may 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 that can function as 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 forms a film on the band-shaped member. This also enables continuous formation of a functional deposition film.

In the method of the present invention, a side wall of a film-forming space on a pillar is formed using the band-shaped member, and microwave energy is uniformly radiated or transmitted in the width direction of the band-shaped member into the column-shaped film-forming space. By confining the microwave in the columnar film forming space, microwave energy is efficiently consumed in the columnar film forming space, and a uniform microwave plasma is generated. The nature also increases. 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.

Of course, even if the band-shaped member is considerably wide, it can cope with the radiation or transmission of microwave energy from the microwave applicator means being kept uniform in the longitudinal direction.

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 it is necessary to prevent the microwave plasma from leaking out of the film formation space. This is also effective in improving the performance and preventing film deposition on unnecessary portions. Specifically, a pressure difference is applied between the inside and outside of the film formation space, an atmosphere of a so-called inert gas having a small ionization cross-sectional area, an atmosphere of H ₂ gas, or the like, or a microwave is actively generated from the inside of the film formation space. It is effective to provide a means that does not cause leakage. As means for preventing microwave leakage, a gap portion connecting the inside and outside of the film forming space is sealed with a conductive member, or the hole diameter is preferably 波長 wavelength or less of the wavelength of microwave used,
More preferably 1/4 wavelength or less wire mesh, 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 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.
Also, by setting the pressure outside the film formation space to be very low compared to the pressure in the film formation space, or by setting the pressure to a very high value, microwave plasma does not occur outside the film formation space. Such conditions can be set.

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. .

In the method of the present invention, the microwave energy is applied by giving a directivity in one direction perpendicular to the traveling direction of the microwave at least substantially uniformly with respect to the length in the width direction of the band-shaped member used from the microwave applicator means. Either a leaky wave type or a slow wave type is preferably used for radiation or transmission. Regardless of the method, care is taken so that the amount of microwave radiation or transmission is uniform in the direction in which the microwave travels. Further, the microwave applicator means separates from microwave plasma generated in the film forming space by a microwave permeable member. By doing so, the microwave energy radiated or transmitted from the microwave applicator means is kept uniform in its longitudinal direction irrespective of changes in the external environment. For example, even in a case where a deposited film is deposited on the outer peripheral wall of the separation means and the absolute amount of microwave transmission changes, the uniformity of the microwave plasma in at least the longitudinal direction is maintained, and By employing a structure in which the separation means can be uniformly and efficiently cooled, it is also possible to avoid local nonuniformity of microwave transmission. Also,
If the cooling of the separating means is sufficiently performed, the method can cope with a considerably high power process.

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 confining the microwave plasma region with the moving band-shaped member, the precursor contributing to the formation of the deposited film generated in the microwave plasma region is formed on the band-shaped member with high yield. Since the capture and further the deposition film can be continuously formed on the belt-like member, the utilization efficiency of the source gas for forming the deposition film can be drastically increased.

Furthermore, by using the microwave applicator means of the present invention, the uniformity of the microwave plasma generated in the longitudinal direction of the microwave applicator means is enhanced, and thus the deposition formed in the width direction of the band-shaped member is improved. Of course, the uniformity of the film is excellent, and the belt-like member is formed in the longitudinal direction of the belt-like substrate by continuously transporting the belt-like member in a direction substantially perpendicular to the longitudinal direction of the microwave applicator means. The uniformity of the deposited film is also excellent.

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

In addition, by using the microwave applicator means of the present invention and changing its pore diameter and aperture ratio variously, it is possible to generate microwave plasma with high uniformity in the longitudinal direction.

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, a mechanical sealing structure using an O-ring, a pocket, a helicopter, a magnetic fluid, or the like, or a diluent gas atmosphere having little or no effect on the characteristics of the deposited film to be formed, Alternatively, it is desirable to provide an isolation container for forming an appropriate vacuum atmosphere around the periphery. In the case of the mechanical sealing structure, special care needs to be taken so that the sealing state can be maintained while the belt-shaped member moves continuously.
In the case where the apparatus of the present invention is connected to a plurality of other deposited film forming means and a deposited film is continuously stacked on the belt-shaped member, it is desirable to connect the respective apparatuses using gas gate means. In the case where only a plurality of the apparatuses of the present invention are connected, the film forming chamber is an independent film forming atmosphere in each apparatus. Therefore, the isolation container may be single or may be provided in each apparatus. good.

In the apparatus of the present invention, the pressure outside the film forming chamber may be in a 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 structure material, it is desirable that the shape substantially the same as the side wall of the film forming chamber is formed of a wire, a thin plate, or the like made of metal, ceramics, reinforced resin, or the like having appropriate strength. In addition, since the auxiliary film is hardly formed on the belt-like member facing the surface of the auxiliary structure that is not exposed to the microwave plasma, the auxiliary structure is 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 structural member into close contact with the band-shaped member, and rotating or moving the auxiliary structural member in synchronization with the transport speed of the band-shaped member, a mesh pattern or the like provided on the auxiliary structural member is transferred onto the band-shaped member. 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,
It is preferable that the material has low distortion and a desired strength, and specifically, a thin plate of a metal such as stainless steel, aluminum and its alloys, iron and its alloys, copper and its alloys, and a composite thereof, and polyimide. , Polyamide, polyethylene terephthalate, epoxy or other heat-resistant resin sheets or composites of these with glass fiber, carbon fiber, boron fiber, metal fibers, etc., and the surfaces of thin sheets of these metals, resin sheets, etc. Metal thin film and / or SiO ₂ , Si ₃ N ₄ , Al ₂ O ₃ , Al
Examples thereof include those obtained by subjecting an insulating thin film of N or the like to a surface coating treatment by a sputter method, a vapor deposition method, a plating method, or the like. 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, preferably
It is desirable that the thickness is 0.01 mm to 5 mm, more preferably 0.02 mm to 2 mm, and most preferably 0.05 mm to 1 mm. Easy to be. The width dimension of the band-shaped member is not particularly limited because the uniformity of the microwave plasma in the longitudinal direction is maintained as long as the microwave applicator means of the present invention is used, but it is to the extent that the curved shape is maintained. Preferably, specifically, preferably from 5 cm to 200
cm, more preferably 10 cm to 150 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, preferably, both ends of the band-shaped member are supported by a support / conveying ring having a desired curved shape, and further curved along the shape, and at least one pair provided in the longitudinal direction of the band-shaped member. By squeezing with a support / transport roller as a bending start end forming means and a bending end end forming means, bending it into a substantially columnar shape, and further applying a driving force to at least one of the support / transport ring and the support / transport roller. The belt-shaped member is conveyed in the longitudinal direction while maintaining the curved shape. The belt may be supported and transported by the support / transport ring only by mere sliding friction, or a sprocket hole may be formed on the belt member, and the support / transport ring may be used. Also, a so-called gear-shaped one having a saw-tooth-shaped projection provided around it may be used.

Regarding the shape of the support / transport ring, it is preferable to form a curved shape, preferably a circular shape, but an elliptical shape, a square shape, and a polygonal shape. 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 on which a field back 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 sputter method, an ion plating method, a CVD method, or the like, or a material formed by processing 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.

It is preferable that the deposited film adhered to the supporting / transporting ring is removed before peeling, scattering, etc. occur, and chemical and physical such as dry etching or post-decomposition wet etching in a vacuum, and bead blasting. It is desirable that it be removed by a technique.

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 supporting / transporting roller in order to prevent the belt-shaped member from being bent, twisted, laterally displaced, and the like during the transportation.

The curved shape formed in the present invention is formed in a columnar shape so as to be close to the separating means or to include the separating 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,
It is desirable to have a polygonal shape or the like and to be substantially symmetrical with respect to the central axis of the microwave applicator means in order to enhance the uniformity of the deposited film. Further, the length of the curved portion determines the volume of the microwave plasma region, and substantially the length of the deposited film formed in correlation with the time during which the band-shaped member is exposed to the microwave plasma region during transportation. The utilization efficiency of the source gas for forming a deposited film is determined based on the ratio of the thickness to the peripheral length of the separation means exposed to the microwave plasma. Therefore, it is desirable that the length of the curved portion is set to preferably not more than five times, more preferably not more than four times the peripheral length of the separating means. In the microwave plasma region, the microwave power density (W / cm ³ ) for maintaining stable microwave plasma depends on the type and flow rate of the raw material gas used, the pressure, microwave radiation of the microwave applicator, It is determined by the correlation between the transmission capacity and the absolute volume of the microwave plasma region, and it is difficult to unambiguously define it.

In the apparatus of the present invention, even if the band-shaped member is not curved and forms a columnar shape, even if it is conveyed in a horizontal or slightly curved shape opposite to the side facing the hole means of the microwave applicator, particularly the microwave is applied. There is no hindrance to the plasma discharge conditions and the like.

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, C, Cr, Cu,
Stainless steel, brass, nichrome, SnO ₂ , In ₂ O ₃ , ZnO,
A so-called simple metal or alloy such as SnO ₂ -In ₂ O ₃ (ITO) and a transparent conductive oxide (TCO) are subjected to surface treatment in advance by plating, vapor deposition, spattering, etc. to form electrodes for current extraction. It is desirable to keep.

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. In the case where 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 formed. It is desirable to deposit and form.

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 fine uneven surface, the uneven shape is spherical, conical, pyramidal, or the like, and its 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.

In the apparatus of the present invention, the separation means is disposed in the vicinity of or protrudes into the film formation chamber, and includes therein a microwave applicator means for radiating or transmitting microwave energy into the film formation chamber. It has. Therefore, the structure is designed to separate the vacuum atmosphere in the film forming chamber from the outside air in which the microwave applicator means is installed, and to withstand the pressure difference existing between the inside and the outside. Specifically, it is preferably a cylindrical shape or a semi-cylindrical shape, and may be a shape having a smooth curved surface as a whole.

In addition, the thickness of the peripheral wall of the separation means is slightly different depending on the material used, but is preferably about 0.5 mm to 5 mm.
mm is desirable. As a material thereof, microwave energy radiated or transmitted from the microwave applicator means can be transmitted into the film formation chamber with a minimum loss, and airtightness which does not cause air to flow into the film formation chamber is generated. Preferred are those having excellent properties, specifically, quartz,
Glass or fine ceramics such as alumina, silicon nitride, beryllia, magnesia, zirconia, boron nitride, and silicon carbide are included.

If the separating means is cylindrical or semi-cylindrical, its diameter (inner diameter) is such that the microwave applicator means used is contained inside it and the microwave applicator means contacts the inner peripheral wall of the separating means. It is desirable that the dimensions be set to the minimum required.

Further, in the separating means, it is desirable to provide a microwave confinement means or a dummy load at an end opposite to a side where the microwave applicator means is inserted. In the former case, it is preferable to cover most of the portion protruding from the end of the band-like member with a conductive member such as a metal or a wire mesh, and to ground the same. Particularly, at a high power level, inconvenient microwave matching may occur. If there is a possibility, it is preferable to provide the latter means.

Further, in the separating means, it is safe to cover a part protruding on the side where the microwave applicator means is inserted with a conductive member such as a metal or a wire mesh, and to ground the waveguide and the isolation container. Above.

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

Specifically, the cooling means may be an air flow flowing along the inner peripheral surface of the separating means, or a shape substantially similar to the separating means and formed concentrically inside the separating means. A conduit may be formed between the enclosure and the separating means, and a cooling fluid such as water, oil, or freon may flow through the conduit.

On the other hand, the separating means such as the cylindrical shape of the present invention may be used together with a usual slow-wave type microwave applicator, in which case the microwave energy transmitted from the slow-wave type microwave applicator is used. Are coupled into the film forming chamber through an evanescent wave. Thus, by utilizing the separation means having a small thickness and cooling the separation means to a sufficiently low temperature, even when microwave energy of relatively high power is introduced into the film forming chamber, the heat generated Thereby, high-electron-density plasma can be generated without causing breakage such as cracks in the separation means.

Further, in the apparatus according to the present invention, film deposition occurs on at least a portion of the outer peripheral surface of the separation means that is in contact with the microwave plasma region, as on the strip-shaped member. Therefore, although depending on the type and characteristics of the film to be deposited, microwave energy radiated and transmitted from the microwave applicator means is absorbed or reflected by the deposited film, and enters the film forming chamber formed by the belt-shaped member. If the amount of radiation and transmission 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
In some cases, the deposition rate of the deposited film to be formed is reduced or the characteristics are changed. In such a case, the film deposited on the separation means is dry-etched, wet-etched,
Alternatively, the initial state can be restored by removing by a mechanical method or the like. In particular, dry etching is preferably used as a method for removing the deposited film while maintaining a vacuum state. Further, the separation means is rotated while maintaining the vacuum, the portion exposed to the microwave plasma is moved out of the microwave plasma region, and the deposited film is removed in a region different from the microwave plasma region. It is also possible to adopt a continuous method of rotating the microwave plasma region. Further, by continuously feeding a sheet made of a material having a microwave permeability substantially equivalent to that of the separating means along the outer peripheral surface of the separating means, a deposited film is attached and formed on the surface of the sheet. Then, it is also possible to adopt a method of discharging the gas outside the microwave plasma region.

The microwave applicator means in the present invention radiates microwave energy supplied from a microwave power supply into the inside of the film forming chamber to convert the deposited film forming raw material gas introduced from the gas introduction means into plasma and maintain the same. It has a structure that can be used. In particular,
A waveguide having an open end at the end is preferably used. Specific examples of the waveguide include a waveguide for microwave transmission such as a circular waveguide, a square waveguide, and an elliptical waveguide. Here, it is possible to prevent the standing wave from hitting at the end of the waveguide by setting the opening end. On the other hand, even if the end of the waveguide is a closed end, there is no particular problem.

In the device of the present invention, the dimensions of the circular waveguide suitably used for the microwave applicator are appropriately designed depending on the frequency band (band) and mode of the microwave used. In designing, it is preferable that transmission loss in the circular waveguide is small, and that consideration is given so that multiple modes do not occur as much as possible.Specifically, other than EIAJ standard circular waveguide, etc., 2.45 GHz In-house standards for use include those with an inner diameter of 90 mm and 100 mm.

Note that transmission of microwaves from a microwave power supply is relatively easy to use, and it is preferable to use a rectangular waveguide. However, in the conversion unit to the circular waveguide used as a microwave applicator, microwave energy is transmitted. It is necessary to minimize the transmission loss, and specifically, it is preferable to use an electromagnetic horn type waveguide for rectangular or circular conversion.

In the present invention, the type of the rectangular waveguide suitably used for the microwave applicator is appropriately selected depending on the frequency band (band) and mode of the microwave used, and at least the cut-off frequency is used. It is preferable that the frequency is smaller than the frequency, specifically, JIS, EIAL, IEC, JAN and other standard products, as its own standard for 2.45GHz, the inner diameter of the square cross section of 96mm width × 27mm height And the like.

In the apparatus of the present invention, as long as the applicator means of the present invention is used, microwave energy supplied from a microwave power supply is efficiently radiated and transmitted into the film forming chamber, so that a problem related to a so-called reflected wave is easily avoided,
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.
In the case where a strong reflected wave is generated due to abnormal discharge or the like before or after the start of discharge, it is desirable to provide the matching circuit to protect the microwave power supply.

The waveguide has at least one hole means for radiating microwave energy on one side thereof, and these hole means are sized and spaced so as to uniformly radiate microwave energy. It is necessary that they are complete, but they may or may not be complete. Specific dimensions and the like will be disclosed in an experimental example described later.

The shape of the hole means formed in the waveguide is desirably substantially rectangular, and when a plurality of holes are formed at desired intervals in the longitudinal direction from near the end of the waveguide,
By opening or closing some of them, uniform microwave plasma is generated in the width direction of the band-shaped member to be used. At this time, the radiated microwave energy has a length of at least one wavelength or more of the radiated microwave in the longitudinal direction of the waveguide, and is preferably radiated almost equally in the width direction of the band-shaped substrate. Is desirable.

When only one hole means is formed, the aspect ratio of the square is large, and the dimension is larger than one wavelength of microwave in the longitudinal direction of the waveguide, and covers almost the entire width and length. It is desirable to be able to open it. In order to increase the uniformity of the microwave energy radiated in the longitudinal direction, a shutter means for adjusting the aperture is provided. The shape of the shutter means is a strip shape, an elongated trapezoidal shape, a shape in which a part of one side of the strip or the elongated trapezoid is cut off in a half moon shape, etc., and is along the surface shape of the waveguide. Preferably, the material is a metal or a resin subjected to a conductive treatment. Then, the end is fixed to a connecting portion provided near the corner of the hole means on the side near the microwave power source, and the opening degree is adjusted using the connecting portion as a fulcrum. It may be fixed for improving the stability of plasma.

When the hole means having a large aspect ratio is used, it is preferable that the length of the long side is substantially equal to the length in the width direction of the band-shaped member to be used.

Further, it is desirable that the shutter means is grounded to the waveguide only at the connection part, and the waveguide and the shutter means are insulated by insulation means at a place other than the connection part. preferable. If a contact is additionally provided between the shutter means and the rectangular waveguide, this is an arc contact.

The microwave applicator means using the hole means described above is a so-called "leakage wave" type microwave radiating structure.

On the other hand, in the present invention, the microwave applicator may be of a slow wave circuit type. When a slow wave circuit is used, most of the microwave energy is transmitted via an evanescent wave. Therefore, microwave energy has the disadvantage that the amount coupled to the plasma decreases sharply with increasing lateral distance to the microwave structure, but in the present invention the microwave applicator is separated from the plasma region. This can solve this drawback.

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

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

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

FIGS. 5 (a) and 5 (b) are schematic side sectional views showing the arrangement of gas introduction pipes in the apparatus of the present invention. In this drawing, only main constituent members are shown. Further, each device will be described in detail in [Example of device] described later.

The example shown in FIG. 5 (a) is a typical example in which three gas introduction pipes 112a, 112b, 112c as gas supply means are provided in a film forming chamber 504 having a shape. Introductory pipe 11
2a, 112b, and 112c are approximately equidistant from the center O of the film forming chamber 504, and the belt-shaped member 101 is formed at an angle of θ ₁ , θ ₂ , and θ ₃ with reference to the center axis HH ′ of the film forming chamber as shown in FIG. Are arranged in parallel with the width direction. And the gas outlets 503a, 503b,
Reference numerals 503c are directed to the adjacent strip-shaped members 101, respectively.

In this arrangement, the gas introduction pipe 112b is connected to the center line H of the film formation chamber 116.
Although it is arranged on H ', it may be arranged at any position shifted to the left or right as desired. In addition, gas introduction pipe 112a,
The distances from the center O of 112b and 112c may be equal or different from each other. Angles θ ₁ , θ ₂ , θ ₃
May also be equal or different from each other.

Raw materials gases for forming a deposited film, which are appropriately mixed as required, are introduced into each of the gas introduction pipes 112a, 112b, 112c while being independently controlled.

The gas outlets 503a, 503b, and 503c are formed in a line on the side surface of each gas introduction pipe at substantially equal intervals, but according to the increase or decrease of the gas introduction amount, the width of the deposited film formed in the width direction is increased. The intervals may be changed as appropriate to improve the uniformity.

Of course, the number of gas introduction pipes may be two or four or more. Further, a rectifying plate may be provided in the film forming chamber in order to improve the separation of the introduced film forming material gas in the film forming chamber.

The example shown in FIG. 5 (b) is a typical example in which three gas introduction pipes 112a, 112b, 112c as gas supply means are provided in a columnar film formation chamber 505. Gas introduction pipes 112a, 112b,
112c is substantially equidistant from the outer peripheral surface of the separation means 109 and θ ₁ , as shown in FIG.
They are arranged at angles of θ ₂ and θ ₃ . The distance between the gas introduction pipes 112a, 112b, 112c and the outer peripheral surface of the separation means 109 may be changed as desired. With such an arrangement, the flow path of the deposition film forming source gas discharged from each gas introduction pipe in the film formation chamber is restricted, and the composition controllability of the deposited film to be formed is improved.

The magnitudes of the angles θ ₁ , θ ₂ , θ ₃ are appropriately determined according to the desired composition of the deposited film.

The number of gas introduction pipes may be two or four or more. The gas outlet is opened similarly to the gas inlet pipe used in FIG. 5 (a).

In the apparatus of the present invention, a bias voltage may be applied to the gas introduction pipe in order to control the plasma potential of the microwave plasma generated in the film formation chamber. The bias voltages applied to the plurality of gas introduction tubes may be equal to each other, or may be different from each other. As the bias voltage, it is desirable to apply a DC, a pulsating current, and an AC voltage alone or by superimposing each of them. In order to effectively apply a bias voltage, it is desirable that the surfaces of both the gas introduction pipe and the belt-shaped member are conductive. By controlling the plasma potential by applying a bias voltage, it is possible to improve plasma stability, reproducibility, film characteristics, and suppress generation of defects.

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, the inside of the film forming chamber and / or the isolation vessel is desirably maintained at a low pressure necessary for operation near the minimum value of the modified Passien 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. Further, the cross-sectional shape of the gas gate is a slit shape or a similar shape, and the dimensions thereof are calculated and designed using a general conductance calculation formula together with the overall length and the exhaust capacity of an exhaust pump to be used. . Furthermore, it is preferable to use a gate gas to enhance the separation capabilities, e.g. Ar, He, Ne, Kr, Xe, diluent gas include a deposited film forming of a rare gas or H ₂ or the like of Rn like. The gate gas flow rate is appropriately determined depending on the conductance of the entire gas gate, the capacity of the exhaust pump used, and the like.
A pressure gradient as generally shown in FIGS. 6 (a) and 6 (b) may be formed. In FIG. 6 (a), there is a point where the pressure becomes maximum at substantially the center of the gas gate, so that the gate gas flows from the center of the gate gas to the vacuum vessel on both sides, and in FIG. Since there is a point where the pressure becomes minimum at the center, the gate gas is also exhausted from the center of the gas gate together with the deposited film forming raw material gas 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, as the deposited film forming means provided in the other vacuum vessel connected to the isolation vessel by the gas gate means, RF plasma CVD, sputtering, reactive sputtering, ion plating, and the like. Means for realizing a method used for forming a so-called functional deposited film, such as a teeing method, a photo CVD method, a thermal CVD method, a MOCVD method, an MBE method, and an HR-CVD method, can be given. 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. Further, in order to obtain a stable discharge, the oscillation mode is desirably a so-called continuous oscillation, and its ripple width is desirably within 30%, more desirably 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.

(Example of device)

Hereinafter, the device of the present invention will be described with reference to the drawings, using a specific device example of the present invention, but the present invention is not limited thereto.

Apparatus Example 1 FIG. 1 shows a schematic diagram of a microwave plasma CVD apparatus of the present invention.

101 is a belt-shaped member, and supports and transports rollers 102 and 10
While being maintained in a cylindrically curved shape by the support ring 3 and the support / transport rings 104 and 105, the substrate is transported in the arrow direction in the figure.
106 and 107 are temperature control mechanisms for heating or cooling the belt-shaped member 101.

Reference numeral 108 denotes a microwave applicator,
Is separated from the microwave plasma region 113. 110 is a metal tube for preventing microwave leakage, and 111 is a wire mesh for preventing microwave leakage. Reference numerals 112a, 112b, and 112c denote gas introduction tubes, respectively, into which a source gas for forming a deposited film is independently introduced via a microcontroller (not shown). When a bias voltage for controlling the plasma potential is applied, a voltage may be applied to the gas introduction pipe from a DC or AC power supply or the like via a conducting wire. At this time, it is desirable to insert an insulating joint into a part of the gas introduction pipe so that a bias voltage is applied only to the film formation space side. Reference numerals 114 and 115 denote microwave meshes for preventing microwave leakage.
Numeral 113 is confined in a film forming chamber having a curved portion of the belt-shaped member 101 as a side wall. The inside of the microwave plasma region 113 is separated by an exhaust device (not shown) by the separating means 109 and the transport roller 1.
The gas is exhausted through the gap between the wires 02 and 103 and / or the wire meshes 114 and 115 for preventing microwave leakage.

FIG. 2 shows a specific schematic diagram of the microwave applicator means 201 used as the microwave applicator 108.

The circular waveguide 202 has a distal end 203 on one side of which a plurality of (here, for example, five) spaced holes 20 are provided.
4 to 208 are opened, and microwaves travel from the direction of the arrow in the figure. Here, as an example, the hole 205 is the waveguide 2
It shows a state where the lid is closed with a lid made of the same material as 02. By opening and closing several holes in this manner, the microwave energy radiated in the longitudinal direction of the waveguide 202 is made uniform.

Apparatus Example 2 In this apparatus example, an apparatus example in which the apparatus shown in Apparatus Example 1 is disposed in an isolated container can be given. FIG. 4 shows a schematic diagram thereof. Reference numeral 400 denotes an isolation container, the inside of which can be evacuated through an exhaust hole 419 using an exhaust pump (not shown). Reference numerals 401 and 402 denote fixing flanges, which are separation means 1 protruding through both walls of the isolation container 400.
09 is fixed. Fixing flanges 401 and 402 are isolated containers
Like the 400, it is preferably made of a suitable corrosion-resistant material such as stainless steel, and is preferably detachable from the isolation container 400. The fixing flange 401 is attached to the connection flange 404. Connecting flange 4
04 is directly attached to the side wall of the isolation container 400, where an opening 405 almost coextensive with the outer peripheral surface of the cylindrical separating means 109 is opened so that the separating means 109 can be inserted. . At least two O-rings 406 and 407 are attached to the fixing flange 401 to separate the vacuum atmosphere in the isolation container 400 from the outside air. Here, a cooling groove 408 is provided between the O-rings 406 and 407, through which a coolant such as water is circulated,
The rings 406 and 407 can be cooled uniformly. As the material for the O-ring, for example, a material that performs its function at a temperature of 100 ° C. or more, such as viton, is preferably used. Here, it is preferable that the O-ring is provided at a position sufficiently distant from the microwave plasma region, so that the O-ring can be prevented from being damaged at a high temperature.

Reference numeral 110 denotes a metal cylinder. A wire mesh 111 is attached to an open end 409 of the metal cylinder, and an electrical contact with the fixing flange 401 is maintained by a grounding finger 410. Leakage is prevented. The wire mesh 111 also has a role of allowing the cooling air of the separating means 109 to flow out. Note that a dummy load for microwave absorption may be connected to the opening end 409. This is particularly useful where leakage of microwave energy at high power levels occurs.

The isolation container 400 is provided with a fixing flange 402 for fixing similarly to the separating means on a side wall opposite to the side wall on which the fixing flange 401 described above is mounted. 411 is a connection flange, 412 is an opening, 413 and 414 are O-rings, 415 is a cooling groove, 416 is a metal cylinder, and 417 is a ground finger. 418 is a connection plate, which connects the microwave applicator means 108, the microwave power supply and the square, the waveguide 403 for circular conversion, and preferably has a structure without leakage of microwave energy here, For example, a chi-yoke flange can be used.
Further, the square / circular conversion waveguide 403 is connected to the square waveguide 421 via a connection flange 420.

FIG. 5 (a) schematically shows a cross-sectional side view of a transport mechanism of the belt-shaped member 101 in the present example of the apparatus.

Here, the arrangement is such that the outer peripheral surface of the separating means 109 has at least two proximity points, and the hole 2
The figure shows a case where a columnar film forming chamber 504 is formed by being curved in a substantially cylindrical shape with respect to the side facing 08. Support / transport rollers 102 and 103 and support / transport rings 104 (105) are used to maintain the cylindrical shape. Here, the width of the support / transport ring 104 (105) should be as small as possible with respect to the width of the belt-shaped member to be used.
This will increase the effective utilization of the film deposited on the substrate. This is because a film to be deposited on the substrate is deposited on the support / transport ring 104 (105).

Further, wire meshes or thin plates 501, 50 for confining the microwave plasma region are provided on both sides of the support / transport rings 104, 105.
1 'is preferably attached (one side is not shown), and the mesh diameter is preferably less than 1/2 wavelength, more preferably less than 1/4 wavelength of the wavelength of the microwave used, and In the case where the exhaust gas is exhausted from the air, it is desirable that the exhaust gas is of such an extent that the permeation of the source gas can be ensured.

Further, the substrate temperature control mechanisms 106 and 107 are for maintaining the temperature of the belt-shaped member 101 constant while passing through the microwave plasma region, and may be a means capable of both heating and / or cooling. desirable. Further, the substrate temperature control mechanism may have a structure directly in contact with the belt-shaped member in order to increase heat exchange efficiency. In general, the temperature of a part exposed to microwave plasma tends to rise, and the degree of the rise varies depending on the type and thickness of the belt-shaped member to be used.

Further, the gaps L1 and L2 at the close point between the outer peripheral surface of the separating means 109 and the strip-shaped member 101 are emitted at least to prevent leakage of microwave energy therefrom and to confine the microwave plasma region in a curved shape. It is preferable to set shorter than half the wavelength of the microwave.
However, the interval L3 between the bending start end and the bending end end of the band-shaped member 101 is because microwave energy radiated from the microwave applicator 201 is efficiently radiated into the curved region formed by the band-shaped member 101. In addition, it is desirable that the wavelength is set to be longer than 1/4 wavelength of the emitted microwave.

Since the microwave energy radiated from the hole 208 is radiated with directivity in a direction substantially perpendicular to the side facing the hole 208, the radiation direction is directed substantially perpendicular to at least the distance L3. Is preferred.

The three gas introduction pipes 112a, 112b, and 112c are substantially equidistant from the center O of the film forming chamber 504 and are set to be θ with respect to the center axis HH ′ of the film forming chamber.
₁ , θ ₂ , and θ ₃ .

Apparatus Example 3 Next, there can be mentioned a case where the microwave applicator means 301 shown in FIG. 3A is used in the apparatus shown in FIG.

An open end 303 and one elongated rectangular hole 304 are formed in the circular waveguide 302, and microwaves travel from the direction of the arrow in the figure. The hole 304 is larger than one wavelength of the microwave to be used, and is formed substantially over one entire surface of the circular waveguide 302. The open end 303 is provided to avoid standing waves, but there is no problem even if it is sealed. With this structure, the microwave energy can be radiated from the entire surface of the hole 304, but the concentration of the microwave energy particularly at the end of the hole near the microwave power supply is maximized. Therefore, the degree of concentration can be adjusted by using at least one shutter 306 attached to the circular waveguide 302 by the connecting portion 305.
FIG. 3 (b) shows a preferred shape of the shutter 306.
As shown in FIG. 3 (d), a strip shape, a trapezoid shape, and a shape in which one side of the strip shape or the trapezoid shape is cut out in a half-moon shape or the like can be given.

The connecting portion 305 includes a groove 307 opened on the side of the shutter 306 close to the microwave power supply, and a fixing pin 308. An insulator 309 made of glass, Teflon, or the like is provided around the hole 304. These are because the shutter 306 is brought into contact with the waveguide 302 only at the connecting portion 305. Here, when a contact is provided between the partial shutter 306 and the waveguide 302, it becomes an arc contact.

Apparatus Examples 4 and 5 In this apparatus example, as shown in the side sectional view of FIG. 5 (b) in the apparatus examples 1 and 2, a case where the strip-shaped member 101 and the separating means 109 are arranged can be mentioned. .

This arrangement shows a case where the belt-shaped member 101 is concentrically curved along the outer peripheral surface of the separating means 109. Here, it is preferable that wire meshes 502, 502 '(one side not shown) for confining the microwave plasma region are attached to both side surfaces of the support / transport rings 104, 105, and the mesh is used for the microwave used. It is desirable that the wavelength of the wave is preferably not more than 1/2 wavelength, more preferably not more than 1/4 wavelength, and of such an extent that the transmission of the source gas can be ensured.

Furthermore, the surface interval L4 of the band-shaped member 101 at the bending start end and the bending end end of the band-shaped member 101 prevents at least radiation of microwave energy therefrom and confine the microwave plasma region within the curved shape. It is necessary to set the wavelength to be shorter than half the wavelength of the microwave to be used.

The relative arrangement of the separating means 109 and the belt-shaped member 101 is preferably concentric,
As long as 9 is wrapped in the curved shape of the band-shaped member 101, the emitted microwave energy is not particularly hindered because it is confined within the curved shape, and the direction in which the hole 208 is directed is not particularly limited. .

Further, the three gas introduction pipes 112a, 112b, 112c are provided in the region surrounded by the separating means 109 and the strip-shaped member 101 with respect to θ ₁ , θ ₂ , θ _{3 based on} the center axis HH ′ of the film forming chamber. Are arranged at an angle.

Apparatus Examples 6 and 7 In Apparatus Examples 4 and 5, the microwave applicator 20 was used.
One having the same configuration except that 1 is changed to the microwave applicator 301 used in the device example 2 can be mentioned.

Apparatus Examples 8 to 11 In Apparatus Examples 1, 2, 4 and 5, the same configuration can be mentioned except that the microwave applicator 201 is a slow wave circuit type microwave applicator (not shown).

Apparatus Example 12 In this apparatus example, as shown in FIG. 7, vacuum containers 701 and 70 for feeding and winding the strip-like member 101 to the microwave plasma CVD apparatus for forming a deposited film shown in Apparatus Example 2 are used.
2 can be mentioned using gas gates 721 and 722.

Reference numeral 703 denotes a feeding bobbin for the belt-like member, and reference numeral 704 denotes a bobbin for winding the belt-like member. The belt-like member is conveyed in the direction of the arrow in the drawing. Of course, this can be reversed and transported. Reference numerals 706 and 707 denote conveying rollers which also serve to adjust the tension and position the belt-shaped member. 712 and 713 are temperature adjusting mechanisms used for preheating or cooling the belt-shaped member. 70
7, 708, 709 are throttle valves for adjusting the displacement, 710,
Exhaust pipes 711 and 720 are connected to an exhaust pump (not shown). 714 and 715 are pressure gauges, and 716 and 717
Is a gate gas introduction pipe, and 718 and 719 are gate gas exhaust pipes, and a gate gas and / or a source gas for forming a deposited film are exhausted by an exhaust pump (not shown). Reference numeral 723 denotes a film forming chamber having the strip-shaped member 101 as a side wall.

Device Example 13 In this device example, as shown in FIG. 8, two more microwave plasma CVs of the present invention were added to the device shown in Device Example 12.
An example in which isolation containers 400-a and 400-b for forming a deposited film by D are connected to both sides so that a stacked device can be manufactured. Each of the two connected deposited film forming apparatuses is provided with one gas introduction pipe.

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 400.

801, 802, 803, 804 are gas gates, 805, 806, 80, respectively
7 and 808 are gate gas introduction pipes, 809, 810, 811 and 812 are gate gas exhaust pipes, and 813 and 814 are gas introduction pipes.

Apparatus Examples 14 and 15 In Apparatus Examples 12 and 13, the microwave applicator 20
One having the same configuration except that 1 is changed to the microwave applicator 301 used in the apparatus example 3 can be mentioned.

Apparatus Examples 16 and 17 In Apparatus Examples 12 and 13, the microwave applicator was used.
A similar configuration can be mentioned except that a slow wave circuit type microwave applicator (not shown) is used for 201.

Apparatus Example 18 In this apparatus example, as shown in FIG. 9, two conventional RF plasma CVD apparatuses are connected to both sides of the apparatus shown in Apparatus Example 12 so that a stacked device can be manufactured. Can be cited.

Here, 901 and 902 are vacuum vessels, 903 and 904 are cathode electrodes for RF application, 905 and 906 are gas introduction tubes and heaters, 907 and 9
08 is a halogen lamp for substrate heating, 909 and 910 are anode electrodes, and 911 and 912 are exhaust pipes.

Other Apparatus Examples For example, in Apparatus Example 13, an isolation container 40 for forming a deposited film is used.
Apparatus with a combination of the various microwave applicators described above for 0, 400-a, 400-b.

Further, there may be mentioned an apparatus in which the apparatus shown in the apparatus example 13 is connected in two or three stations, an apparatus in which a deposition film forming means by the RF plasma CVD method is mixed and connected.

Further, there can be mentioned, for example, devices in which the arrangement of the strip member and the microwave applicator in the device examples 12 and 13 is the same as that described in the device examples 4 and 5.

Further, in Apparatus Examples 1, 2, 3, 12, 13, etc., an apparatus in which a rectifying plate is provided in a film forming chamber can be mentioned.

An example of a semiconductor device suitably manufactured by the method and apparatus of the present invention is a solar cell. FIGS. 10A to 10D schematically show typical examples of the layer structure.

The example shown in FIG. 10A shows that the lower electrode 10
02, a photovoltaic element 1000 in which an n-type semiconductor layer 1003, an i-type semiconductor layer 1004, a p-type semiconductor layer 1005, a transparent electrode 1006, and a current collecting electrode 1007 are formed in this order. Note that it is assumed that light is incident from the transparent electrode 1006 side in the present photovoltaic element.

In the example shown in FIG. 10B, a transparent electrode 1006, a p-type semiconductor layer 1005, an i-type semiconductor layer 1004, and n
This is a photovoltaic element 1000 ′ in which a mold semiconductor layer 1003 and a lower electrode 1002 are formed in this order. In this photovoltaic element, it is assumed that light is incident from the light-transmitting support 1001 side.

An example shown in FIG. 10 (C) is a so-called pin-type photovoltaic element 1011 and 1012 using two types of semiconductor layers having different band gaps and / or different layer thicknesses as i-layers. This is a tandem photovoltaic element 1013. Reference numeral 1001 denotes a support, and a lower electrode 1002, an n-type semiconductor layer 1003, an i-type semiconductor layer 1004, a p-type semiconductor layer 1005, an n-type semiconductor layer 1008,
The i-type semiconductor layer 1009, the p-type semiconductor layer 1010, the transparent electrode 1006, and the current collecting electrode 1007 are formed in this order, and it is assumed that light is incident from the transparent electrode 1006 side in the present photovoltaic element. .

The example shown in FIG. 10 (D) is configured by laminating three pin-junction photovoltaic elements 1020, 1021, 1023 using three types of semiconductor layers having different band gaps and / or layer thicknesses as i-layers. In addition, a so-called triple type photovoltaic element 1024 is used. 1001 is a support, a lower electrode 1002, an n-type semiconductor layer
1003, i-type semiconductor layer 1004, p-type semiconductor layer 1005, n-type semiconductor layer 1014, i-type semiconductor layer 1015, p-type semiconductor layer 1016, n-type semiconductor layer 1017, i-type semiconductor layer 1018, p-type semiconductor layer 1019,
The transparent electrode 1006 and the current collecting electrode 1007 are stacked in this order, and it is assumed that light is incident from the transparent electrode 1006 side in the present photovoltaic element.

In any of the photovoltaic elements, the n-type semiconductor layer and the p-type semiconductor layer can be used in a different order of lamination according to the purpose.

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

Support The support 1001 used in the present invention is preferably made of a material capable of forming a flexible curved shape, and may be a conductive material or an electrically insulating material. Good. Further, they may be light-transmitting or non-light-transmitting, but when light is incident from the side of the support 1001, they are light-transmitting. It is necessary.

Specifically, the belt-like member used in the present invention can be mentioned, and by using the substrate, a solar cell to be manufactured can be reduced in weight, improved in strength, reduced in transportation space, and the like.

Electrode In the photovoltaic element of the present invention, an appropriate electrode is selected and used depending on the configuration of the element. Examples of these electrodes include a lower electrode, an upper electrode (transparent electrode), and a collecting electrode. (However, the upper electrode referred to here indicates the electrode provided on the light incident side, and the lower electrode indicates the electrode provided opposite to the upper electrode with the semiconductor layer interposed therebetween.) The electrodes are described in detail below.

(I) Lower Electrode As the lower electrode 1002 used in the present invention, the surface on which light for generating photovoltaic light is irradiated differs depending on whether or not the material of the above-described support 1001 is translucent (for example, When the support 1001 is a non-translucent material such as a metal, light for photovoltaic generation is irradiated from the transparent electrode 1006 side as shown in FIG. 1 (A).) Location is different.

Specifically, in the case of a layer configuration as shown in FIGS. 10A, 10C, and 10D, it is provided between the support 1001 and the n-type semiconductor layer 1003. However, when the support 1001 is conductive, the support can also serve as the lower electrode.
However, if the sheet resistance is high even when the support 1001 encounters conductivity, as a low-resistance electrode for extracting current,
Alternatively, the electrode 1002 may be provided for the purpose of increasing the reflectance on the support surface and effectively using incident light.

In the case of FIG. 10 (B), a light-transmitting support 1001 is used, and light enters from the support 1001 side. For the purpose of current extraction and light reflection at the electrode, A lower electrode 1002 is provided to face the support 1001 with the semiconductor layer interposed therebetween.

When an electrically insulating material is used as the support 1001, a lower electrode 1002 is provided between the support 1001 and the n-type semiconductor layer 1003 as an electrode for extracting current.

As electrode materials, Ag, Au, Pt, Ni, Cr, Cu, Al, T
metals such as i, Zn, Mo, W or alloys thereof;
These metal thin films are formed by vacuum evaporation, electron beam evaporation, sputtering, or the like. Also, care must be taken that the formed metal thin film does not become a resistance component 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 1002 and the n-type semiconductor layer 1003. The effect of the diffusion prevention layer is not only to prevent the metal element forming the electrode 1002 from diffusing into the n-type semiconductor layer, but also to provide a slight resistance value, and to provide the semiconductor element between the semiconductor layers. The effect of preventing a short-circuit caused by a defect such as a pinhole between the lower electrode 1002 and the transparent electrode 1006, and generating multiple interference by a thin film and confining incident light in a photovoltaic element can be given. be able to.

(Ii) Upper electrode (transparent electrode) The transparent electrode 1006 used in the present invention has a light transmittance of 85% or more in order to efficiently absorb light from the sun or white fluorescent light into the semiconductor layer. Desirably,
Further, the sheet resistance is desirably 100Ω or less so that the output of the photovoltaic element does not become a resistance component. SnO ₂ as a material having such properties,
Metal thin film made of metal oxide such as In ₂ O ₃ , ZnO, CdO, Cd ₂ SnO ₄ , ITO (In ₂ O ₃ + SnO ₂ ) and metal such as Au, Al, Cu etc. And the like. The transparent electrode is laminated on the p-type semiconductor layer 1005 in FIGS. 10 (A), (C) and (D), and is laminated on the substrate 1001 in FIG. 10 (B). Therefore, it is necessary to select ones having good adhesion to each other. These fabrication methods include:
A resistance heating evaporation method, an electron beam 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 1007 used in the present invention is a transparent electrode.
It is provided on the transparent electrode 1106 for the purpose of reducing the surface resistance value of 1006. Ag, Cr, Ni, Al, Ag, A
A thin film of a metal such as u, Ti, Pt, Cu, Mo, W, or an alloy thereof may be used. These thin films can be stacked and used. The shape and area of the semiconductor layer are appropriately designed so that the amount of light incident on the semiconductor layer is sufficiently ensured.

For example, it is desirable that the shape is uniformly spread 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 The semiconductor material constituting the i-type semiconductor layer suitably used in the present photovoltaic device includes A-Si: H, A-Si: F, A-
Si: H: F, A-SiC: H, A-SiC: F, A-SiC: H: F, A-SiGe: H, AS
iGe: F, A-SiGe: H: F, poly-Si: H, poly-Si: F, poly-Si:
In addition to so-called group IV and group IV alloy semiconductor materials such as H: F, II-
Group VI and III-V so-called compound semiconductor materials and the like can be mentioned.

A-SiGe: H, a-SiGe: F, a-SiGe: H: F, a-SiC: H, a
When a so-called group IV alloy semiconductor such as -Si: F or a-SiC: H: F is used for the i-type semiconductor layer, the bandgap from the light incident side (band gap: Eg ^opt ) is appropriately changed. It has been proposed that the open-circuit voltage (Voc) and the fill factor (FF) can be greatly improved. (20th IEEE PVSC,
1988, A NOVEL DESIGN FOR AMORPHOUS SILICON SOLARSE
LLS, S. Guha. J. Yang et al.) FIGS. 11 (a) to 11 (d) show specific examples of bandgap profiles. The mark → in the figure indicates the light incident side.

The bandgap profile shown in FIG. 11 (a) has a constant bandgap from the light incident side. No.
The bandgap profile shown in FIG. 11 (b) is of a type in which the bandgap on the light incident side is narrow and the bandgap gradually widens, and is effective in improving FF. No.
The bandgap profile shown in FIG. 11 (c) is of a type in which the bandgap on the light incident side is wide and the bandgap gradually narrows, and is effective in improving Voc. The bandgap profile shown in FIG. 11 (d) is of a type in which the bandgap on the light incident side is wide, the bandgap narrows relatively steeply, and spreads again. By combining with FIG. 11 (c), both effects can be obtained simultaneously.

According to the method and apparatus of the present invention, for example, a-Si: H (Eg
^{Using opt} = 1.72 eV) and a-SiGe: H (Eg ^opt = 1.45 eV), an i-type semiconductor layer having a bandgap profile shown in FIG. 11D can be manufactured. Also, a-SiC: H
Using (Eg ^opt = 2.05 eV) and a-Si: H (Eg ^opt = 1.72 eV), an i-type semiconductor layer having a bandgap profile shown in FIG. 11C can be manufactured. I can do it.

Further, a semiconductor layer having a doping profile shown in FIGS. 12 (a) to 12 (d) can be manufactured by the method and the apparatus of the present invention. The mark → in the figure indicates the light incident side.

FIG. 12A shows a profile of a non-doped i-type semiconductor layer. On the other hand, FIG. 12 (b) shows a type in which the Fermi level on the light incident side is closer to the valence band and the Fermi level is gradually closer to the conduction band. Is effective in increasing FIG. 12 (c) shows a type in which the Fermi level gradually approaches the valence band from the light incident side.
When the mold semiconductor layer is provided, the same effect as in the case of FIG. 12 (b) is obtained. FIG. 12 (d) shows a type in which the Fermi level changes to the conduction band due to the valence band almost continuously from the light incident side.

These illustrate the case where the band gap is constant from the light incident side shown in FIG. 11 (a), but FIG. 11 (b)
Also in the case of the bandgap profile shown in FIG. 11 (d), the fermi level can be controlled similarly.

By appropriately designing the bandgap profile and the fermi-level profile, a photovoltaic element having high photoelectric conversion efficiency can be manufactured. In particular, these profiles are desirably applied to the i-type semiconductor layer of the tandem-type or triple-type photovoltaic element shown in FIGS. 10 (c) to 10 (d).

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 Continuous deposition of amorphous silicon germanium was performed using the continuous microwave plasma CVD apparatus (FIG. 7) shown in Apparatus Example 12. The microwave applicator used was No. 13 type.

First, a sufficiently degreased and cleaned SUS430BA strip-shaped substrate (width 60 cm ×
A wound bobbin 703 (length 100 m × thickness 0.2 mm) is set, and the strip-shaped member 101 is attached to the gas gate 721 and the isolation container 40.
The tension was adjusted to a level without sag through the transfer mechanism in FIG. 7 and further through the gas gate 722 to the vacuum vessel 702 having the substrate take-up mechanism. Curved shape of the band-shaped member,
Table 18 shows the conditions such as the arrangement of gas introduction pipes. As the gas supply means, a gas supply means having three gas introduction pipes having the configuration shown in FIG. 5A was used.

Therefore, each of the vacuum vessels 701 and 702 and the isolation vessel 400 are 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. While maintaining the substrate surface temperature at 280 ° C., a vacuum was drawn to 5 × 10 ⁻⁶ Torr or less by an oil diffusion pump (not shown) (HS-32 manufactured by Varian) using 107.

At the time when the degassing was sufficiently performed, the raw material gas for forming the deposited film was introduced from each gas introduction pipe under the conditions shown in Table 19, and the opening of the throttle valve attached to the oil diffusion pump was adjusted. The pressure in the film forming chamber 723 was maintained at 12 mTorr by adjustment. At this time, the pressure inside the isolation container 400 was 4 mTorr. When the pressure stabilizes, apply microwave power of 1.2 kW in effective power from a microwave power supply (not shown) to applicator 3.
Emitted from 01. Immediately, the introduced raw material gas is turned into plasma to form a microwave plasma region, and the microwave plasma region is provided with wire nets 501, 501 'attached to the side surfaces of the transfer rings 104, 105 (wire diameter 1 mm, interval 5 mm). Did not leak out to the vacuum vessel side, and no microwave leakage was detected.

Therefore, the supporting / transporting rollers 102 and 103 and the supporting / transporting rings 104 and 105 (both driving mechanisms are not shown) were started, and the transport speed of the belt-shaped member 102 was controlled to be 1.2 m / min. .

The gas gates 721 and 722 are connected to the gate gas introduction pipe 71.
H ₂ gas was flowed at 50 sccm from 6, 717 as a gate gas, and exhausted from exhaust holes 718, 718 by an oil diffusion pump (not shown), and the gas gate internal pressure was controlled to 1 mTorr.

A deposited film was formed continuously for 30 minutes after the start of transport. In addition, since a long strip-shaped member is used, after the end of this manufacturing example, another deposition film is continuously formed, and after all the depositions are completed, the strip-shaped member is cooled and taken out.
The thickness distribution of the deposited film on the belt-shaped member formed in this production example was measured within 5% in the width direction and the longitudinal direction, and was found to be within 5%. The deposition rate was 44 ° / sec on average.

A part of the substrate on which the deposited film was formed was arbitrarily cut out at six locations, and the composition of the deposited film in the depth direction was analyzed using SIMS (ims-3f manufactured by CAMECA). The depth profile shown in FIG. An isle was obtained, and it was found that a bandgap profile shown in FIG. 11 (b) was formed. The total amount of hydrogen in the film was determined using a hydrogen-in-metal analyzer (EMGA-1100, manufactured by HORIBA, Ltd.) to be 18 ± 2 atomic%.

Production Example 2 Following the deposition film formation process performed in Production Example 1, the introduction of the used raw material gas was stopped, and the internal pressure of the isolation container 400 was evacuated to 5 × 10 ⁻⁶ Torr or less. Under the conditions, the source gas for forming the deposited film is introduced from each gas introduction pipe, the internal pressure is maintained at 10 mtorr, and the microwave power is 1.1 kW
A deposited film was continuously formed under the same conditions except that the above conditions were satisfied.

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 51Å / sec.

Six portions of the substrate on which the deposited film was formed were arbitrarily cut out, and the composition of the deposited film in the depth direction was analyzed using SIMS (ims-3f manufactured by CAMECA). The depth profile shown in FIG. 14 was obtained. An isle was obtained, and it was found that a bandgap profile shown in FIG. 11 (d) was formed. The total amount of hydrogen in the film was determined using a hydrogen-in-metal analyzer (EMGA-1100, manufactured by HORIBA, Ltd.) and found to be 17 ± 2 atomic%.

Production Example 3 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 400 was evacuated to 5 × 10 ⁻⁶ Torr or less. Under the conditions, the source gas for forming the deposited film is introduced from each gas introduction pipe, the internal pressure is maintained at 19 mtorr, and the microwave power is 1.8 kW
A deposited film was continuously formed under the same conditions except that the above conditions were satisfied.

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 55Å / sec.

Six portions of the substrate on which the deposited film was formed were arbitrarily cut out, and the composition of the deposited film in the depth direction was analyzed using SIMS (ims-3f manufactured by CAMECA). The depth profile shown in FIG. 15 was obtained. An isle was obtained, and it was found that the bandgap profile shown in FIG. 11 (c) was formed. The total 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 After the internal pressure of the isolation vessel 400 was evacuated to 5 × 10 ⁻⁶ Torr or less in the same manner as in the deposited film formation process performed in Production Example 1, the deposited film was passed through each gas introduction pipe under the conditions shown in Table 22. A deposition film was formed under the same conditions except that a forming material gas was introduced, the internal pressure was maintained at 6 mtorr, and the microwave power was set to 1.9 kW.

In this production example, the microwave applicator used was No. 18 type.

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 112Å / sec.

Six portions of the substrate on which the deposited film was formed were arbitrarily cut out, and the composition of the deposited film was analyzed in the depth direction using SIMS (ims-3f manufactured by CAMECA). The depth profile shown in FIG. 16 was obtained. An isle was obtained, and it was found that a doping profile almost as shown in FIG. 12 (b) was formed. The total amount of hydrogen in the film was determined using a hydrogen-in-metal analyzer (EMGA-1100, manufactured by HORIBA, Ltd.) and found to be 17 ± 2 atomic%.

Production Example 5 In the continuous microwave plasma CVD apparatus (FIG. 7) shown in Apparatus Example 12, an apparatus in which the arrangement of the band member and the microwave applicator was the same as that described in Apparatus Example 5 was used, and Continuous deposition of as silicon germanium was performed. The microwave applicator used was No. 8 type.

After evacuating the internal pressure of the isolation container 400 to 5 × 10 ⁻⁶ Torr or less in the same manner as in the deposited film formation process performed in Production Example 1, the deposition was performed from each gas introduction pipe under the same conditions as shown in Table 19. A deposition film was formed under the same conditions except that a film forming raw material gas was introduced, the internal pressure was maintained at 11 mtorr, and the microwave power was set at 1.2 kW.

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.

Six parts of the substrate on which the deposited film was formed were arbitrarily cut out, and the composition analysis in the depth direction of the deposited film was performed using SIMS (ims-3f manufactured by CAMECA). And a depth profile similar to Hobo was obtained.
It was found that the handgear profile shown in FIG. In addition, hydrogen analyzer in metal (EMGA-1100,
HORIBA, Ltd.) to determine the total amount of hydrogen in the film
It was 19 ± 2 atomic%.

Production Example 6 In this production example, a pin-type photovoltaic element having a layer configuration shown in the schematic cross-sectional view of FIG. 10A was produced using the apparatus shown in FIG.

The photovoltaic element comprises a substrate 1001, a lower electrode 1002, an n-type semiconductor layer 1003, an i-type semiconductor layer 1004 having a bandgap profile shown in FIG.
5. This is a photovoltaic element 1000 in which a transparent electrode 1006 and a collecting electrode 1007 are formed in this order. Note that it is assumed that light is incident from the transparent electrode 1006 side in the present photovoltaic element.

First, a SUS430BA strip-shaped substrate similar to that used in Production Example 1 was set in a continuous sputter device, and a 1000 mm Ag thin film was continuously formed using an Ag (99.99%) electrode as a target, and ZnO (99.999%) continuously. 1.2 using electrodes as targets
A μm ZnO thin film was sputter-deposited to form a lower electrode 1002.

Subsequently, the strip-shaped substrate on which the lower electrode 1002 was formed was set in the continuous deposition film forming apparatus shown in FIG. 8 in the same manner as in Production Example 1. Table 23 shows conditions such as the curved shape of the substrate in the isolation container 400 at this time. Further, under the conditions shown in Table 24, a source gas for forming a deposited film was introduced from each gas introduction pipe.

In the isolation containers 400-a and 400-b, the n-type a-Si: H: F film and the p ⁺ -type μc-Si: H: F were deposited under the deposition film forming conditions shown in Table 25.
A film was formed.

First, microwave plasma is generated in each film forming chamber, and when the discharge or the like is stabilized, the belt-shaped member 101 is transported from the left side to the right side in the drawing at a transport speed of 48 cm / min. A 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, using a continuous modularization apparatus.
A 35 cm × 70 cm solar cell module was produced continuously.

For the fabricated solar cell module, AM1.5 (100mW
/ cm ² ) When the characteristics were evaluated under light irradiation, a photoelectric conversion efficiency of 7.5% 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.
It fell within 9.5%.

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

Manufacturing Example 7 In this manufacturing example, in the pin-type photovoltaic element manufactured in Manufacturing Example 6, the bandgear shown in FIG. 11C was used instead of the a-SiGe: H: F film as the i-type semiconductor layer. An example using an a-SiC: H: F film having a profile will be described.

The a-SiC: H: F film was prepared by introducing a raw material gas for forming a deposited film from each gas introduction tube under the conditions shown in Table 26, maintaining the surface temperature of the belt-shaped member at 270 ° C., and maintaining the internal pressure at 16 mTorr. The wave power was formed at 1.8 kW. And the transfer speed is 42cm / min
Other semiconductor layers were formed and modularized in the same manner and in the same manner as in Production Example 6, except that the solar cell module was fabricated.

For the fabricated solar cell module, AM1.5 (100mW
/ cm ² ) When the characteristics were evaluated under light irradiation, a photoelectric conversion efficiency of 6.8% 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.
It fell within 9.5%.

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

Manufacturing Example 8 In this manufacturing example, in the pin-type photovoltaic element manufactured in Manufacturing Example 6, the fermilevel shown in FIG. 12B was used instead of the a-SiGe: H: F film as the i-type semiconductor layer. An example using an a-Si: H: F film having a profile will be described.

The a-Si: H: F film was prepared by introducing a raw material gas for forming a deposited film from each gas introduction pipe under the conditions shown in Table 27, maintaining the surface temperature of the belt-shaped member at 270 ° C., and maintaining the internal pressure at 7 mTorr. Wave power
It was formed as 1.3kW. Then, another semiconductor layer was formed and formed into a module by the same operation and method as in Production Example 6 except that the transfer speed was set to 44 cm / min, 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, more than 8.5% in photoelectric conversion efficiency being obtained, further variations in characteristics among modules is 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.
It fell within 9.5%.

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

Production Example 9 In this production example, a photovoltaic element having a layer configuration shown in FIG. 10 (C) was produced. At the time of fabrication, isolation containers 400-a ', 400', and 400-b 'having the same configuration as the isolation containers 400-a, 400, and 400-b in the apparatus shown in FIG. A connected device (not shown) was used.

The band-shaped member was made of the same material and treated as used in Production Example 1, and the lower cell was produced in Production Example 6.
The upper cell has the same layer configuration as that produced in Production Example 8, and the production condition of each semiconductor layer is such that the surface temperature of the belt-like member is 270 ° C., 270 ° C., 260 ° C., 260 ° C. 250
The temperature was the same as in each of the production examples except that the temperature was set at 250 ° C.
The module-forming step was performed in the same operation and method as in Production Example 6 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, more than 10.6% in photoelectric conversion efficiency being obtained, further variations in characteristics among modules is 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 5kW power supply system could be made.

Production Example 10 In this production example, a photovoltaic element having a layer configuration shown in FIG. 10 (C) was produced. At the time of fabrication, in the apparatus shown in FIG. 4, isolation containers having the same configuration as the isolation containers 400-a, 400, and 400-b are connected to the isolation containers 400-a ', 400', and 400-b 'in this order via a gas gate. A connected 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 has the same layer configuration as that produced in Production Example 7, and the production condition of each semiconductor layer is such that the surface temperature of the belt-like member is 260 ° C., 260 ° C., 250 ° C., 250 ° C. 240
The temperature was the same as in each of the production examples except that the temperature was 230 ° C.
The module-forming step was performed in the same operation and method as in Production Example 6 to produce a solar cell module.

For the fabricated solar cell module, AM1.5 (100mW
/ cm ² ) When the characteristics were evaluated under light irradiation, a photoelectric conversion efficiency of 10.5% or more was obtained, and the variation in characteristics among the modules was within 5%.

Further, the rate of change of the photoelectric conversion efficiency with respect to the initial value after continuous irradiation of AM1.5 (100 mW / cm ² ) light for 500 hours was within 9%.

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

Production Example 11 In this production example, a photovoltaic element having a layer configuration shown in FIG. 10D was produced. In the production, the isolation containers 400-a ′, 400 ′, 400-b ′, 400-a ″, 400 ″, having the same configuration as the isolation containers 400-a, 400, 400-b in the apparatus shown in FIG. 400
-b ″ was connected in this order via a gas gate (not shown).

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 6.
The intermediate cell has the same layer configuration as that of the production example 8 and the upper cell has the same layer constitution as that of the production example 7, and the conditions for producing the deposited film of each semiconductor layer are shown in Tables 28 to 29. The module-forming step was performed in the same operation and method as in Production Example 6 to produce a solar cell module.

For the fabricated solar cell module, AM1.5 (100mW
/ cm ² ) When the characteristics were evaluated under light irradiation, a photoelectric conversion efficiency of 10.8% or more was obtained, and the variation in characteristics among the 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 8.5%.

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

[Summary of Effects of the Invention] According to the method of the present invention, a belt-like member constituting a side wall of a film forming space is continuously moved, and two or more kinds of deposited films having different compositions are formed in the film forming space. The raw material gases are separately introduced through a plurality of gas supply means, respectively, and have directivity in the width direction of the band-shaped member forming the side wall of the film forming space, and in one direction perpendicular to the traveling direction of the microwave. The microwave energy is radiated from the microwave applicator means for uniformly radiating or transmitting the microwave energy, and the microwave plasma is confined in the film forming space, thereby forming a large-area composition-controlled functional deposition film. It can be continuously formed with good reproducibility.

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

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 variously changing the shape, length, and transfer speed of the curve, a deposited film having an arbitrary composition distribution and 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, the functional deposition film whose composition is controlled with good uniformity can be formed continuously on the surface of a comparatively wide and long strip-shaped member. Therefore, it can be suitably used particularly as a mass-producing machine for high-efficiency 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 is possible to form a deposited film under a low pressure, which suppresses the generation of polysilane powder and suppresses the polymerization of active species, thereby reducing defects, improving film characteristics, and stabilizing film characteristics. Can be improved.

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

Further, the solar cell manufactured by the method and the apparatus of the present invention has 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. 2 and 3 (a) to (d) are schematic diagrams of the microwave applicator means of the present invention.
FIG. 4 is a schematic cross-sectional view of a microwave plasma CVD apparatus according to the present invention. 5 (a) and 5 (b) are side sectional views schematically showing the arrangement of the belt-shaped member transport mechanism and the gas introduction pipe in the present invention. FIG. 6 is a diagram schematically showing a pressure gradient of gas skating means in the present invention.
Each of FIGS. 7 to 9 is an overall schematic view of an example of the continuous microwave plasma CVD apparatus of the present invention. 10 (A) to 10 (D) are schematic cross-sectional views of a pin type photovoltaic element (single, tandem, triple) manufactured in the present invention. 12 (a) to 12 (d) are views for explaining a method of processing a band-shaped member. FIGS. 11 (a) to 11 (d) are views for explaining a bandgap profile of a deposited film formed according to the present invention. FIG. 13 to FIG. 16 are views showing the depth profiles of the component elements of the deposited films formed in Production Examples 1 to 5 of the present invention. 1 to 10, 101... Belt-shaped members 102 and 103... Transport rollers 104 and 105... Transport rings 106 and 107... Temperature control mechanism 108... Microwave applicator 109. Means 110, 416: Metal cylinder 111: Wire mesh 112a, b, c, 813, 814: Gas introduction tube 113: Microwave plasma region 114, 115: Wire mesh for preventing microwave leakage 201, 301: Micro Wave applicator 202, 303 Circular waveguide 203 End 204, 205, 206, 207, 208, 304 Hole 303 Open end 305 Connection 306 Shutter 307 Groove 308 … Fixing pin 309 …… Insulator 400 …… Isolated container 401, 402 …… Fixing flange 403 …… Square, circular conversion waveguide 404,411 …… Connecting flange 405,412 …… Opening 406,407 , 413, 414 O-ring 408, 415 Cooling groove 409 Open end 410, 417 Ground finger 418 Connection plate 4 19 exhaust port 420 connection flange 421 square waveguide 501, 501 ', 502, 502' wire mesh 701, 702, 901, 902 vacuum container 703 delivery bobbin 704 winding Take-up bobbin 705, 706… Transport rollers 707, 708, 709… Throttle bubble 710, 711, 718, 719, 720… Exhaust vent 712, 713 , 717, 805, 806, 807, 808 ... gate gas inlet pipes 721, 722, 801, 802, 803, 804 ... gas gate 723 ... film forming chambers 809, 810, 811, 812 ... gate gas exhaust pipes 903, 904 ... Cathode electrodes 905, 906 ... Gas introduction tubes 907, 908 ... Halogen lamps 909, 910 ... Anode electrodes 911, 912 ... Exhaust tubes 1000, 1000 ', 1011, 1012, 1020, 1021, 1023 ... pin
Junction type photovoltaic elements 1005, 1010, 1016, 1019 p-type semiconductor layer 1006 top electrode 1007 current collecting electrode 1013 tandem photovoltaic element 1024 triple photovoltaic element

Claims (30)

(57) [Claims] 1. A belt-like member is moved in a longitudinal direction, and a film forming space having a side wall on the band-like member is formed in the middle of the band-like member, and at least two kinds of depositions having different compositions are formed in the formed film-forming space. Each of the film forming source gases is separately introduced through a plurality of gas supply means, and at the same time, the microwave energy is uniformly radiated or transmitted in one direction perpendicular to the microwave traveling direction. The microwave applicator radiates or transmits the microwave energy toward the band-shaped member in the film forming space to generate microwave plasma in the film forming space, and the side wall exposed to the microwave plasma A method for forming a deposited film by microwave plasma CVD, comprising forming a deposited film on the belt-like member constituting the above. 2. In the middle of the band-shaped member, the bending start end forming unit and the bending end end forming unit are used to interpose the band-shaped member between the bending start end forming unit and the bending end end forming unit. The method according to claim 1, wherein the band-shaped member is curved while leaving a gap in a longitudinal direction to form a side wall of the film forming space. 3. A microwave energy is radiated or transmitted into the film forming space from a gap left in a longitudinal direction of the band-shaped member between the bending start end forming means and the bending end end forming means. 3. The method for forming a deposited film according to item 2. 4. The microwave applicator means is inserted into the film-forming space from one of two opposing side surfaces of a film-forming space formed with the band-shaped member as a side wall, and the microwave energy is applied to the film-forming space. The method for forming a deposited film according to claim 1, wherein the deposited film is radiated or transmitted into a film forming space. 5. The microwave energy radiated or transmitted from said microwave applicator means is transmitted through microwave energy provided between said film forming space and said applicator means, and is transmitted through said film forming space. 2. The method according to claim 1, wherein the film is radiated or transmitted into the film forming space via a separation unit that separates the film from outside air. 6. The microwave applicator means is disposed close to and substantially parallel to the width direction of the belt-shaped member within a range not to contact the separation means, and a microwave energy is provided in the film forming space. 6. The method according to claim 5, wherein radiation is transmitted or transmitted. 7. The method according to claim 6, wherein the microwave applicator radiates or transmits uniform microwave energy to a length substantially equal to that of the band-shaped member. 8. The method according to claim 7, wherein the microwave applicator is separated from the microwave plasma generated in the film forming space via the separating means. 9. The method according to claim 1, wherein microwave energy radiated or transmitted into the film formation space is prevented from leaking out of the film formation space. 10. The gas supply means is disposed in parallel with the width direction of the band-shaped member constituting the side wall, and the deposition film forming raw material gas is discharged in one direction toward the adjacent band-shaped member. The method for forming a deposited film according to claim 1. 11. A deposition film forming apparatus for moving a belt-shaped member in a longitudinal direction and forming a deposited film on said belt-shaped member in the middle thereof, wherein said deposition-film forming apparatus is provided between said belt-shaped members in a longitudinal direction to support said belt-shaped member. A film forming space is provided in the middle of moving from the feeding mechanism to the winding mechanism in the longitudinal direction by a set of rollers arranged in parallel with each other with a predetermined space, and the band-shaped member functions as a wall. Film forming space forming means for supporting the band-shaped member for forming, and directing in one direction perpendicular to the traveling direction of the microwave toward the band-shaped member arranged in the film forming space. A microwave applicator connected to the film formation space for uniformly introducing microwave energy to generate microwave plasma in the film formation space; and a microwave plasma generator generated in the film formation space. Separating means for separating the applicator means from the gas; exhaust means for exhausting the inside of the film forming space; at least two or more gas supplies for introducing a deposition film forming material gas into the film forming space And a temperature control unit for heating or cooling the belt-shaped member. 12. The roller comprises a curved portion forming means for curving the band-shaped member, and the curved portion forming means comprises at least one set of a curved start end forming means and a curved end end forming means. 12. The deposition film forming apparatus according to claim 11, wherein the film forming space is provided between the bending start end forming unit and the bending end end forming unit. 13. The roller set has at least a pair of support / transport rollers, wherein the rollers constitute curved portion forming means, and the curved portion forming means has a support / transport ring. 3. The deposited film forming apparatus according to item 1. 14. The separation means is disposed substantially parallel to a gap left between the curved start end forming means and the curved end end forming means, and is disposed outside the film forming chamber. 13. The apparatus for forming a deposited film according to claim 12. 15. The deposited film forming apparatus according to claim 11, wherein said film forming space forming means comprises a set of said rollers and a support conveyance ring disposed between said rollers. 16. The apparatus according to claim 12, wherein said separating means protrudes from one of the side surfaces of said film forming space into said film forming chamber so as to be substantially parallel to a width direction of said strip-shaped member. Deposition film forming equipment. 17. The apparatus of claim 17, wherein said separating means is substantially cylindrical.
12. The deposited film forming apparatus according to 11. 18. An apparatus according to claim 11, wherein said separation means is substantially semi-cylindrical. 19. The microwave applicator means comprising:
18. The deposition film forming apparatus according to claim 17, wherein the deposition film forming apparatus is provided so as to be separated from a peripheral wall of the separating means and included inside the separating means. 20. The deposited film forming apparatus according to claim 11, wherein said separating means is provided with a cooling means. 21. The deposited film forming apparatus according to claim 20, wherein said cooling means is an air flow flowing along an inner peripheral surface of said separating means. 22. The separating means is provided with a cooling means, and the cooling means is provided inside the separating means and has a conduit structure through which a cooling medium can flow between the separating means. , Configured to be concentric with the separating means.
18. The deposited film forming apparatus according to item 17. 23. The microwave applicator means is a waveguide for microwave transmission, and the microwave energy is applied to the waveguide substantially uniformly in the longitudinal direction thereof in a direction perpendicular to the traveling direction of the microwave. 12. The deposited film forming apparatus according to claim 11, wherein a substantially rectangular hole is provided in order to provide directionality and uniformly radiate the direction. 24. The deposited film forming apparatus according to claim 23, wherein at least one of said rectangular holes is formed on one side of said waveguide, and microwaves are radiated from said holes. 25. The deposition film forming apparatus according to claim 24, wherein a plurality of said rectangular holes are arranged at intervals in a longitudinal direction of said waveguide. 26. The deposited film forming apparatus according to claim 25, wherein said rectangular hole is a rectangle provided over the entire space corresponding to the film formation space and larger than one wavelength of microwave. 27. The deposited film forming apparatus according to claim 26, further comprising shutter means corresponding to said rectangular hole. 28. The gas supply means is disposed in parallel with the width direction of the strip-shaped member constituting the side wall.
3. The deposited film forming apparatus according to item 1. 29. The deposited film forming apparatus according to claim 28, wherein the gas supply means is provided with a gas discharge hole directed to a belt-like member constituting the adjacent side wall. 30. The deposited film forming apparatus according to claim 11, wherein the microwave includes an evanescent microwave.