JP2819030B2 - Method and apparatus for continuously forming large-area functional deposition film by microwave plasma CVD - Google Patents

Description

Description: TECHNICAL FIELD [0001] The present invention uses a novel microwave energy supply device capable of generating uniform microwave plasma over a large area, and a plasma reaction caused by the device. The present invention relates to a method and an apparatus for continuously forming a large-area 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. Japanese Patent Application Laid-Open Publication No. 2003-229,1991 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,
Serious radioactive contamination, which is typified by the Chernobyl nuclear power plant accident, harms the human body and invades the natural environment, threatening the future spread of nuclear power generation. There are even countries that have banned laws.

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

Against this background, population growth in developing countries and the accompanying increase in demand for electricity is inevitable.
The power supply problem must be considered on a global scale, coupled with an increase in power consumption per capita due to the further promotion of electronics in lifestyles in advanced countries.

Under such circumstances, the power generation method using solar cells using sunlight does not cause the above-mentioned problems such as radioactive contamination and global warming, and the sunlight falls all over the earth. Energy sources are less unevenly distributed, and relatively high power generation efficiency can be obtained without the need for complicated large-scale facilities, so that it can respond to future increases in power demand without causing environmental destruction. Attention has been paid to a clean power generation system, and various research and developments have been made for practical use.

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

By the way, in order to supply necessary electricity in a general household,
Where a solar cell with an output of about 3 kW per household is required, if the photoelectric conversion efficiency of the solar cell is, for example, about 10%, the area of the solar cell for obtaining the required output is about 30 m ² Becomes For example, in order to supply necessary electric power to 100,000 households, a solar cell having an area of 3,000,000 m ² is required.

For this reason, a gaseous raw material gas such as silane, which is easily available, is used, and is decomposed by glow discharge to deposit a semiconductor thin film such as amorphous silicon on a relatively inexpensive substrate such as glass or a metal sheet. Solar cells that can be manufactured by such a method are attracting attention because of their high mass productivity and the possibility that they can be manufactured at a lower cost than solar cells manufactured using single-crystal silicon or the like. Has been made.

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

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

Looking at this point, solar cells using thin-film semiconductors such as amorphous silicon, which have attracted attention,
In the production, 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. For this reason, in order to manufacture an amorphous silicon-based solar cell, a method has been proposed in which an independent film formation chamber for forming each semiconductor layer is provided, and each semiconductor layer is formed in the film formation chamber. ing.

Incidentally, 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, means for separating the glow discharge regions from each other by a slit-shaped separation passage and further forming a flow of a scavenging gas such as Ar or H _{2 in the} separation passage is employed. . From this, it can be said that this roll-to-roll system is suitable for mass production of semiconductor devices.

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

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

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

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

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

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

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 Journal of Vacuum Science Technology (Journa
l of Vacuum Science Technology) B-4 (January-February 1986) pp. 295-298 and B-4 (January-February 1986) pp. 126-130. Can be According to these reports, microwave plasma disks,
A microwave reactor called 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, microwave plasma discs designed to operate at 2.45 GHz
In the source, the confinement diameter of the plasma is at most
Is about 10cm, at most 118cm ³ even if the plasma volume
This is not enough to say that the area is large. 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 further states that the discharge can be extended to diameters greater than 1 m by operating at lower frequencies, for example 400 MHz. 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. Patent Publication and JP-A-57-133636
And various reports have been made by academic societies on the formation of various semiconductor thin films using this high-density plasma.
ECR plasma CVD equipment has been commercialized.

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

Furthermore, the characteristics of the deposited film formed are not at a level that can be said to be equivalent to those formed by the conventional RF plasma CVD method, and the deposited film is formed in a space where ECR conditions are satisfied. The characteristics and the deposition rate are extremely different between the deposited film outside the ECR condition and the deposited film formed in the so-called scattered magnetic field space, so it is a method suitable for the fabrication of semiconductor devices that require particularly 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 a liquid crystal display and photoelectric conversion elements and switching elements for contact-type image sensors, 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 method and apparatus for forming a thin-film semiconductor device and provides a novel method and apparatus for forming a high-quality functional deposition film uniformly over a large area at a high speed. The purpose is to provide.

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

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

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 method and an apparatus for uniformly controlling plasma potential of a microwave plasma generated over a large area and a large volume with good reproducibility and stability.

It is a further object of the present invention to provide a novel method and apparatus for forming a high-quality functional deposition film having excellent quality and uniformity by controlling the plasma potential of microwave plasma.

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

[Structure and effect of the invention]

The present inventors have solved the above-mentioned problems in the conventional thin film semiconductor device forming apparatus, and have conducted intensive 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. Inject the raw material gas for forming a deposited film into the film forming chamber, maintain a predetermined pressure, and supply a microwave from a microwave power supply to the microwave applicator means,
When a bias voltage is applied to a bias applying unit that is disposed separately from the belt-shaped member, uniform microwave plasma can be generated in the film forming chamber in the longitudinal direction of the applicator unit, and the plasma potential is reduced. The knowledge that it can be controlled was obtained.

The present invention has been completed as a result of further studies based on the above-mentioned findings, and continuously forms a large-area functional deposited film by a microwave plasma CVD method having a main point as described below. Methods and apparatus.

The method of the present invention is as follows. That is, the band-shaped member is moved in the longitudinal direction, a film-forming space having a side wall on the band-shaped member is formed in the middle thereof, and a raw material gas for forming a deposited film is formed in the formed film-forming space via a gas supply unit. At the same time, the microwave energy is uniformly radiated or transmitted in one direction perpendicular to the traveling direction of the microwave by the microwave applicator means, the microwave energy is applied to the microwave in the film forming space. The band-like portion constituting the side wall exposed to the microwave plasma is generated by radiating or transmitting the microwave toward the belt-like member to generate microwave plasma in the film forming space and controlling the plasma potential of the microwave plasma. This is a method for forming a deposited film by a microwave plasma CVD method, which comprises forming a deposited film on a 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.

In the method according to the present invention, the plasma potential is controlled via bias applying means separated from the belt-shaped member.

And the bias applying means is disposed so that at least a part thereof is in contact with the microwave plasma,
A bias voltage is applied to the bias applying unit, and at least a portion of the bias applying unit that is in contact with the microwave plasma is subjected to a conductive treatment.

Further, DC, pulsating current and / or AC are preferably used as the bias voltage.

In the method of the present invention, the bias applying means may also serve as the gas supply means, or may be provided separately from the gas supply means.

The bias applying means is constituted by a single or a plurality of bias rods.

In the method of the present invention, the plasma potential may be controlled by a bias voltage applied to the belt-shaped member, and the gas supply unit is set to a ground potential, and at least a part thereof is arranged so as to be in contact with the microwave plasma. To be installed.

Then, at least a part of the gas supply means which is in contact with the microwave plasma is subjected to a conductive treatment.

In the method of the present invention, microwave energy radiated or transmitted from the microwave applicator means is supplied to the inside of the film formation space via a microwave permeable member provided between the film formation space and the applicator means. To radiate or transmit.

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, at least a conductive treatment is performed on a surface of the belt-shaped member on a side exposed to the microwave plasma.

Further, the device of the present invention is as follows. That is, a deposition film forming apparatus that moves a belt-like member in the longitudinal direction and forms a deposition film on the belt-like member in the middle thereof, and a predetermined space is provided between them in the longitudinal direction to support the belt-like member. It is provided on the way of moving from the feeding mechanism to the winding mechanism in the longitudinal direction by a set of rollers that are separated and arranged in parallel with each other to form a film forming space in which the band-shaped member functions as a wall. Film-forming space forming means for supporting the band-shaped member, and introducing microwave energy toward 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, and the microwave application generated from the microwave plasma generated in the film formation space. Separation means for separating the deposition means, exhaust means for exhausting the inside of the film formation space, gas supply means for introducing a deposition film forming raw material gas into the film formation space, plasma potential of the microwave plasma Biasing means for applying a bias voltage for controlling the temperature, a temperature controlling means for heating or cooling the strip-shaped member, and a bias applying means for controlling the plasma potential of the microwave plasma. This is a deposited film forming apparatus characterized by the following.

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

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

In the apparatus of the present invention, the bias applying means is provided separately from the belt-shaped member.

And the bias applying means is disposed so that at least a part thereof is in contact with the microwave plasma,
A bias voltage is applied to the bias applying unit. At least a part of the bias applying unit that is in contact with the microwave plasma is subjected to a conductive process.

Further, the bias voltage may be DC, pulsating, and / or
Alternatively, AC is preferably used.

In the apparatus of the present invention, the bias applying unit may also serve as the gas supply unit, or may be provided separately from the gas supply unit.

The bias applying means includes one or a plurality of bias rods.

In the apparatus of the present invention, when the bias applying means is also provided as the band-shaped member, the gas supply means is grounded and at least a part thereof is provided so as to be in contact with the microwave plasma.

Then, a conductive treatment is performed on at least a part of the gas supply unit that is in contact with the microwave plasma.

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.

Also, the square hole is provided with shutter means 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, at least a conductive treatment is performed on a surface of the band-shaped member that is exposed to the microwave plasma.

Further, the apparatus of the present invention is an apparatus for continuously forming a functional deposition film on a continuously moving strip member by a microwave plasma CVD method, wherein the strip member is continuously moved in a longitudinal direction thereof. And a column-shaped film-forming chamber formed with the band-shaped member as a side wall and capable of holding the inside of the member substantially at a vacuum, through a curved portion forming means for bending in the middle thereof. Microwave applicator means for transmitting evanescent microwave energy with directivity in one direction perpendicular to the traveling direction of microwaves for generating microwave plasma in the film chamber; and the microwave applicator. Means for transmitting evanescent microwave energy transmitted with directivity in one direction perpendicular to the traveling direction of microwaves into the film forming chamber. Separating means for separating the microwave applicator means from microwave plasma generated in the film forming chamber by the evanescent microwave energy, and exhaust means for evacuating the film forming chamber; Gas supply means for introducing a source gas for forming a deposited film into a chamber, bias applying means for controlling the plasma potential of the microwave plasma, and temperature control means for heating and / or cooling the strip-shaped member A continuous deposition device for a functional deposition film, wherein a deposition film is continuously formed on a surface of the belt-shaped member on a side exposed to the microwave plasma. .

In the apparatus of the present invention, the microwave applicator means is an elongated slow-wave circuit waveguide, and the slow-wave circuit waveguide substantially uniformly emits evanescent microwave energy 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.

[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 member and the separation means, etc., for uniformly forming a high-quality functional deposition film on the strip member. Various experiments were conducted, and will be described in detail below.

Experimental Examples 1 to 9 In this experimental example, in the apparatus having the configuration shown in the apparatus example 1 described later, the side of the transport rings 104 and 105 was used as an exhaust hole, and connected to an exhaust pump (not shown). Experiments and evaluations were performed on the stability of plasma and the like under microwave plasma discharge conditions shown in Table 2 using a waveguide and a microwave applicator having a hole processing dimension.
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 this experimental example, an apparatus having the configuration shown in Apparatus Example 5 described later, in which the arrangement of the band-shaped member and the microwave applicator was arranged as shown in FIG. Experiments and evaluations were performed on the stability of plasma and the like under the microwave plasma discharge conditions shown in Table 4 using microwave applicators having various waveguides and hole processing dimensions 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 this experimental example, in the apparatus having the structure shown in the apparatus example 3 described later, the side of the conveying rings 104 and 105 was used as an exhaust hole, and connected to an exhaust pump (not shown). Experiments and evaluations were performed on the stability of plasma and the like under the microwave plasma discharge conditions shown in Table 2 using waveguides, holes and shutter processing dimensions. Table 7 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 29 to 38 In this experimental example, in a device having a configuration shown in a device example 7 described below, various microwaves and holes shown in Table 6, and microwave applicators having shutter processing dimensions were used.
Further, under the microwave plasma discharge conditions shown in Table 4,
Experiments and evaluations were performed on plasma stability and the like. Table 8 shows the evaluation results. In this discharge experiment,
The test was performed when the belt-shaped member was stopped 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.

Experimental Example 39 In this experimental example, a bias applying means having a configuration shown in FIG. 13 (A) was provided in an isolated container 400 using an apparatus shown in Apparatus Example 12 (FIG. 7) to be described later. The controllability of microwave plasma, the influence on the plasma potential and the film quality when the DC bias application voltage to the bias application tube 1303 also serving as the gas introduction tube was changed was examined.

Plasma was generated under the same microwave plasma discharge conditions as shown in Table 2 except that the bias application voltage was changed from -300 V to +300 V in increments of 10 V. No. 11 microwave applicator was used. The surface temperature of the belt-shaped member was set to 250 ° C., and the transfer speed was set to 60 cm / min. The discharge was maintained for 10 minutes after each bias voltage was applied.

FIG. 14 shows the results of obtaining the current-voltage characteristics between the bias applying tube and the belt-shaped member when applying the bias by setting the bias applied voltage on the X axis and the bias current value on the Y axis.

At the same time, a diameter 0.3 mm, the probe method using a single probe with a tungsten wire of length 3 mm (exposed portion), to measure the plasma potential V _b during bias application, when not applying a bias plasma potential V Rate of change Δ to ₀
FIG. 15 shows the result of _obtaining V _b (= V _b / V ₀ ). In addition, the single probe was disposed substantially at the center of the curved portion of the band-shaped member and approximately 5 cm from the inner surface.

In these results, although there is a change depending on the type and flow rate of the source gas for discharge, the bias voltage is generally −22.
When the voltage is 0 V or lower or +220 V or higher, abnormal discharge such as spark occurs in the film forming chamber, and it is difficult to maintain a stable discharge state.

However, when the discharge condition of the microwave plasma was constant, the current-voltage characteristics showed a linear relationship that almost increased with an increase in the bias voltage, and it was found that the plasma potential also showed an increasing trend with an increase in the bias voltage.
That is, by changing the bias voltage, the plasma potential was easily stabilized and controlled with good reproducibility.

Subsequently, a 5 mm x 5 mm sample piece was cut out of the film deposited and formed on the SUS430BA thin plate as a band-shaped member, and the surface state was measured with an ultra-high-resolution, low-acceleration FE-SEM (Hitachi, Ltd. S
-900 type), the bias voltage was -300V
In the range of from +10 V to +10 V, surface roughness of several hundreds to several thousands of degrees was conspicuous, but in the range of +10 V to +200 V, the film surface tended to be substantially smoothed with an increase in bias voltage. Then, in the range exceeding +200 V, the film surface began to be roughened again, and in particular, the occurrence of pinholes was observed on the sample surface where abnormal discharge frequently occurred beyond +220 V.

In addition, under the condition that the microwave power is constant, as the flow ratio of the source gas having a large ionization cross section such as SiH ₄ increases, the slope of the current-voltage characteristics increases, while the ionization of H ₂ It was found that the slope of the current-voltage characteristics became smaller as the flow ratio of the source gas having a smaller area increased.

Comparative Experimental Example 1 The current-voltage characteristics were measured under the same conditions as in Experimental Example 39 except that the bias applying tube 1303 serving also as a gas introducing tube was changed from a nickel tube to an aluminum tube.
However, when the bias application voltage was increased from 0 V to about +70 V, the bias application tube 1303 began to deform,
Eventually, a phenomenon of fusing was observed. Further, when the same measurement was performed by changing the bias applying tube 1303 to a copper or brass tube, the same phenomenon as described above was observed. On the other hand, the bias application tube 1303 was made of high melting point metal such as stainless steel, titanium, vanadium, niobium, tantalum, molybdenum, tungsten, etc. When the same measurement was performed instead of the above, deformation was observed when the bias applied voltage exceeded +130 V when stainless steel was used. In the case of using other materials, almost the same measurement results as those obtained in Experimental Example 39 were obtained, and no particular phenomenon such as deformation was observed.

Comparative Experimental Example 2 In Experimental Example 39, a SUS430BA thin plate was used as a band-shaped member.
PET (polyethylene terephthalate) sheet (thickness 0.8
mm), the current-voltage characteristics were measured under the same conditions except for changing to mm). However, although the value of the current flowing even when the bias application voltage was applied to either the positive or negative side showed almost the same value as that obtained in Experimental Example 39, the start of abnormal discharge in the film formation chamber was started. The voltage was about -110V or + 110V. When the state was visually observed, a spark was generated between the bias applying tube and the roller for supporting and transporting the band-shaped member, and the spark exhibited a charge-up phenomenon due to the insulating property of the band-shaped member used. It was found that excessive current was flowing through the supporting / transporting roller, which was made of only a conductive member except for the bias applying tube in the film chamber.

Further, the surface state of the deposited film was observed and evaluated by the same method as that performed in Experimental Example 39, and the film surface was found to be about several hundreds to several thousand degrees regardless of the difference in bias applied voltage. The surface was still rough.

Comparative Experimental Example 3 In Experimental Example 39, the position of the bias applying tube 1303 serving also as a gas introduction tube disposed in the film forming chamber was set near the central axis of the film forming chamber (FIG. 5A, the position of O). From the direction of OH ', OH, OA, OA' in FIG.
The current-voltage characteristics were measured under the same conditions, except that the distance was shifted by 30 mm each by mm. In the case of 120 mm and 150 mm in the OA 'direction, the same measurement was performed.

As a result, when it was shifted by 30 mm and 60 mm in the directions of OH ', OH, OA, and OA', exactly the same results as in Experimental Example 39 were obtained. 90
When shifted by mm, the start voltage of abnormal discharge such as spark slightly changed, but otherwise the same result as in Experimental Example 39 was obtained. On the other hand, when it is shifted by 120 mm or 150 mm in the OA 'direction, since the source gas is not sufficiently supplied into the film forming chamber in the first place, the plasma is not stably generated, and the bias voltage is applied. However, almost no bias current flowed, and it was found that it was difficult to control the plasma potential.

EXPERIMENTAL EXAMPLE 40 In this experimental example, the apparatus having the configuration used in Experimental Example 39 was used, and the bias voltage of various waveforms and frequency conditions shown in Table 9 was applied to the bias applying tube 1303 to generate the microwave plasma. The controllability, the influence on the plasma potential and the film quality, etc. were examined. The microwave plasma discharge conditions and the like were the same as in Experimental Example 39.

The bias voltage is obtained by amplifying various waveform outputs generated by a function generator (HP8116A manufactured by Hewlett-Packard) with a precision power amplifier (4500 series manufactured by NF Circuit Block and custom-ordered products), or a self-made rectifier circuit The output from the device was applied to a bias application tube 1303 via a coaxial cable.

Table 9 shows the results of evaluating the controllability of the plasma potential based on the state of discharge, the change rate of the plasma potential, and observation of the film surface. From these results, it was found that the effect of applying the bias voltage in a relatively wide frequency range was recognized.

Furthermore, when the frequency of the bias voltage is fixed and the maximum amplitude voltage is variously changed, a tendency substantially similar to that of the experimental example 39, that is, a tendency similar to that when the DC voltage is changed is observed. The frequency of abnormal discharge such as spark increased due to the increase of the maximum amplitude voltage.

From these results, even when various bias voltages other than the DC voltage are applied to the bias applying tube, the plasma potential can be easily changed by changing the bias voltage.
It was found that control could be performed stably and with good reproducibility.

Experimental Example 41 In this experimental example, current-voltage characteristics were measured under the same conditions as in Experimental Example 39, except that the bias applying means was changed to the configuration shown in FIG. 13 (B).

As a result, almost the same results as in Experimental Example 39 were obtained.Even if the gas introduction pipe 1305 and the bias rod 1304 were independently provided, the plasma potential was easily and stably changed by changing the bias voltage. It was found that control could be performed with good reproducibility.

Experimental Example 42 In this experimental example, current-voltage characteristics were measured under the same conditions as in experimental example 39 except that the bias applying means was changed to the configuration shown in FIG. 13 (C).

As a result, the starting voltage of abnormal discharges such as sparks changed slightly. At that time, almost all experiments were conducted except for the occurrence of abnormal discharges at the contact between the support / transport ring and the belt-shaped member in the film forming chamber. The same results as in Example 39 were obtained. However, the bias voltage at which the film surface was smoothed had a polarity completely opposite to that in the case of Experimental Example 39, that is, in the range of −10 V to −180 V. Of course, the plasma was stable within this voltage range.

Therefore, it has been found that the plasma potential can be easily, stably, and reproducibly controlled by applying a bias voltage to the belt-like member and disposing the earth rod 1305 also serving as a gas introduction pipe in the film forming chamber.

Experimental Example 43 In this experimental example, the bias applying means was changed to the configuration shown in FIG.
A DC bias voltage was applied under the same conditions as in 41, and independently of this, the controllability of the microwave plasma and the plasma potential when a voltage of 1/4 of the DC voltage applied to the bias rod 1304 was applied to the bias rod 1306 And the effects on the film quality were examined. The microwave plasma discharge conditions and the like were the same as in Experimental Example 39.

As a result, almost the same results as in Experimental Example 39 were obtained except that the frequency of occurrence of abnormal discharge such as sparks was reduced and the stability of plasma was improved.

Therefore, it was found that the plasma potential can be easily, stably and reproducibly controlled by arranging a plurality of bias rods in the film-forming material and applying a bias voltage independently of each other.

Experimental Example 44 In the present experimental example, the bias voltage applied to the bias rod 1304 in the experimental example 43 was changed to a DC voltage, and bias voltages having various waveforms and frequencies similar to those performed in the experimental example 40 were applied. The controllability of the microwave plasma, the influence on the plasma potential and the film quality, etc. were examined.
The microwave plasma discharge conditions and the like were the same as in Experimental Example 39.

As a result, almost the same results as in Experimental Example 39 were obtained except that the frequency of occurrence of abnormal discharge such as sparks was reduced, the starting voltage of abnormal discharge was slightly lowered, and the stability of plasma was improved.

Therefore, it has been found that the plasma potential can be easily, stably, and reproducibly controlled by disposing a plurality of bias rods in the film forming chamber and applying a bias voltage independently of each other.

Experimental Examples 45 and 46 In Experimental Examples 41 and 42, when an experiment was performed in which the same bias voltage was applied as in Experimental Example 40, almost the same effects as obtained in Experimental Examples 41 and 42 were obtained. Admitted.

Comparative Experimental Examples 4 to 7 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 10. 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 8 to 11 In Experimental Examples 2, 7, 21 and 25, of the microwave plasma discharge conditions shown in Table 2, the other conditions were not changed and only the microwave power was varied as shown in Table 11. The plasma state at that time was evaluated from the viewpoints of stability, uniformity, etc., and the case where the most stable state was obtained was evaluated as ◎, and the case where 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 due to ×, and the evaluation results are shown in Table 11. 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 12 to 15 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 12. Is changed variously, 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 no discharge was performed or abnormal discharge, etc. was impractical was 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.

In Comparative Experiment Example 16-19 Experimental Examples 2,7,21 and 25, of the microwave plasma discharge conditions shown in Table 2, various changes only L ₃ as shown in Table 13 without changing the other conditions Then, the state of the plasma at that time was evaluated from the viewpoints of stability, uniformity, etc., and the case where the most stable state was obtained was ◎, and the case where the stability was slightly lacking but there was no practical problem was ○.場合, when there is no practical problem due to lack of stability and uniformity, and when it was not practical due to no discharge or abnormal discharge, etc., was ranked as ×, and their evaluation results in Table 13 showed that.

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 20 to 23 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 inner diameter of the curved shape was changed as shown in Table 14. By variously changing
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., and it is impractical are ranked as × .The evaluation results are shown in Table 14. Indicated.

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-shaped member was transported at a transport speed of 1.5 m / min.

Comparative Experimental Examples 24-27 In Experimental Examples 11, 18, 30, and 37, of the microwave plasma discharge conditions shown in Table 4,
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 15 shows the results of those evaluations.

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 28 to 31 In Experimental Examples 11, 18, 30, and 37, among the microwave plasma discharge conditions shown in Table 4, other conditions were not changed.
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 with practical use are ranked as △, and cases where no discharge is performed or abnormal discharge etc. are impractical are ranked as ×, and those evaluation results are shown in Table 16. 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 32-35 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 L ₄ was changed variously, and the state of the plasma at that time was evaluated from the viewpoints of stability, uniformity, etc., and the case where the most stable state was obtained was ◎, slightly stable, uniformity If there is no practical problem but lacks, rank ○ if there is a practical problem due to lack of stability and uniformity, and × if it is not practical due to no discharge or abnormal discharge etc. Table 17 shows the evaluation results.

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 36 to 39 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 18.

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 40 to 43 In Experimental Examples 1 and 40, except that the punching board for confining the microwave region was changed to a thin plate made of SUS316L which was sprayed with alumina, 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
mTorr, more preferably 3-10 mTorr to 100-200 mTorr
It turned out to be. Regarding the microwave power, preferably 300 to 700 W to 3000 to 5000 W, more preferably 300 to 700 W
It turned out to be ~ 700W ~ 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.

Further, in the method and the apparatus of the present invention, in order to control the plasma potential of the microwave plasma, a bias voltage applying means is provided in a film formation chamber in which the plasma is confined, and various DC voltages or pulses are applied to the bias applying means. It has been found that it is desirable to apply a bias voltage having various waveforms, frequencies, and a maximum amplitude voltage with a current and an AC voltage. Further, it has been found that the bias voltage applying means may also serve as a gas introduction pipe, or may be a bias rod provided separately from the gas introduction pipe. It has been found that the plasma potential can be controlled almost in the same manner even when a bias voltage is applied to the belt-like member. It has been found that when the bias voltage is a DC voltage, the voltage is preferably set to +10 V to +200 V as a measure for improving the film characteristics.

Hereinafter, the method and apparatus of the present invention will be described in more detail based on the facts found by the above-mentioned [experiment].

In the method of the present invention, most of the side wall of the columnar film-forming space formed by bending the band-shaped member using the bending start end forming unit and the bending end end forming unit in the middle of the moving band-shaped member. Is formed of the moving strip-shaped member, and a gap is left between the bending start end forming means and the bending end end forming means in the longitudinal direction of the strip-shaped member.

In the method of the present invention, it is preferable that an inner wall surface of the film forming space has conductivity necessary for a bias current having a desired current density to flow. For this purpose, first, it is preferable that the belt-like member is made of a conductive material, but it is necessary that at least a surface facing the film formation space be subjected to a conductive treatment.

In the method of the present invention, in order to control the plasma potential of the microwave plasma, it is desirable to dispose a bias applying unit so that at least a part thereof contacts plasma generated in the film forming space. The bias applying unit may also serve as a gas supply unit for introducing a deposition film forming source gas into the film formation space, or a single or a plurality of bias rods provided separately from the gas supply unit. It may be.

In the former case, a bias voltage is applied to a so-called gas supply system such as a raw material gas cylinder, a flow control system, and piping through a gas supply means so that an accident such as electric shock or damage to the control system does not occur. It is desirable that the supply system and the gas supply to which the bias voltage is applied be insulated and separated in the middle. Preferably, the position where the insulation is separated is close to the film forming space.

It is desirable that at least a part of the bias applying unit also serving as the gas supply unit that is in contact with the microwave plasma is subjected to a conductive process so that the bias voltage is applied. ,
The material must be considered so that fusing or the like does not occur. Specifically, it is desirable that the coating is performed by coating the high melting point metal or the high melting point ceramic with the high melting point metal.

Further, the position where the bias applying means also serving as the gas supply means is disposed in the film forming space is disposed in contact with the microwave plasma because the microwave plasma acts as a substantially uniform conductor. It is not particularly limited as long as it is provided, but in order to suppress the occurrence of abnormal discharge and the like, it is desirable to dispose it at a distance of preferably at least 10 mm, more preferably at least 20 mm from the inner surface of the band-shaped member.

On the other hand, in the latter case, the material constituting the bias rod and the position at which it is disposed are considered in the same manner as in the case where the bias applying means also functions as the gas supply means. However, it is preferable that the gas supply means is formed of a dielectric material in order to suppress the occurrence of abnormal discharge and to form a uniform plasma potential in the film formation space. In, there is no particular limitation on the material.

In the method of the present invention, when a single bias applying means serving also as the bias rod or the gas supply means is provided, a DC voltage, a pulsating current, and an AC voltage are applied as a bias voltage alone or by superimposing each of them. When a plurality of the bias rods are provided, a DC voltage of the same voltage or a different voltage may be applied to each of the bias rods.
DC, pulsating, and AC voltages may be applied alone or in a superimposed manner. By applying a plurality of types of bias voltages, not only the control range of the plasma potential is expanded, but also the stability, reproducibility and film characteristics of the plasma are improved, and the occurrence of defects is suppressed. As the AC voltage,
Preferable examples include a sine wave, a square wave, a triangular wave, a pulse wave, and a waveform in which these are superimposed. The pulsating voltage preferably includes a waveform obtained by half-wave rectification or full-wave rectification of the AC voltage, a ramp wave, and the like. Further, the DC voltage or the maximum amplitude voltage of the bias voltage is appropriately set in consideration of various characteristics of the deposited film to be formed, the occurrence rate of defects, and the like. Although it may be kept constant until the end time, it is preferable to change it continuously or at an appropriate cycle in order to control the characteristics of the deposited film to be formed and to suppress the occurrence of defects. In particular, when an abnormal discharge such as a spark occurs, a sharp change in the bias voltage occurs. Therefore, the bias voltage is detected electrically, and the bias voltage is immediately reduced or temporarily stopped, and the predetermined bias is again applied. It is preferable to return to the voltage in order to suppress the occurrence of defects in the deposited film. Of course, these steps may be performed manually, but it is preferable to provide an automatic control circuit in the control circuit of the bias applying means from the viewpoint of improving the yield of the deposited film.

In the method of the present invention, the bias applying means may also serve as the band-shaped member. In this case, a ground electrode is provided in the film forming space. The ground electrode may also serve as the gas supply unit.

In the method of the present invention, the band-shaped member is a conductive material,
Alternatively, the surface of the insulating material is subjected to a conductive treatment, but at least at a temperature at which the band-shaped member is heated and held at the time of forming a deposited film, a conductivity at which a sufficient current density is ensured. It is necessary to be made of a material having the above. Specific examples include so-called metals and semiconductors. In addition, a region partially formed of an insulating member may be provided on the belt-shaped member for the purpose of facilitating the element isolation process. On the other hand, when the area of the region constituted by the insulating member is large, the deposition film with the controlled plasma potential is not formed in that region. A film having substantially the same characteristics as the film formed on the substrate is formed.

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 more desirable to cover with a wire mesh of less than 1/4 wavelength, a punching board or the like.

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 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 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. It is desirable that the forming means be supported so as not to cause wrinkles, sagging, 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 order to uniformly and stably generate and maintain the microwave plasma in the columnar deposition space, the shape and volume of the deposition space, the type and flow rate of the source gas introduced into the deposition space, Although there are optimal conditions for the pressure in the film formation space, the amount of microwave energy radiated or transmitted into the film formation space, the matching of microwaves, and the applied bias voltage, these parameters are mutually organic. It is not necessarily 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 microwave applicator means for uniformly radiating or transmitting microwave energy in the width direction of the belt-shaped member to be formed, and adjusting and optimizing the conditions for generating / maintaining microwave plasma and the conditions for applying bias, a great deal of A high-quality functional deposition film can be continuously formed over the area with good uniformity and reproducibility.

Further, according to the method of the present invention, by appropriately controlling the plasma potential, a high-quality functional deposition film having desired characteristics and few defects can be continuously and efficiently formed at a high yield. .

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 a function of physically and chemically isolating an atmosphere space for film formation, that is, a film formation space and an atmosphere space not involved in film formation. This means, for example, a function of forming atmospheres with different gas compositions and states, restricting the flow direction of gas, and forming atmospheres with different pressure differences.

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

Therefore, the atmosphere outside the film formation space configured with the strip-shaped member as a side wall is in a state considerably different from the inside of the film formation space in the gas composition, its state, pressure, and the like.

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

On the other hand, the method of the present invention uses a band-shaped member that can function as a support for forming a functional deposited film as a side wall of the film formation space, and exhibits a function as the structural material.
It is also possible to continuously form a functional deposition film on the belt-like member.

In the method of the present invention, a side wall of a columnar film-forming space 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 microwaves in the columnar deposition space, microwave energy is efficiently consumed in the columnar deposition space, uniform microwave plasma is generated, and uniformity of the deposited film formed Also increase. 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.

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

In 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.

Further, according to the apparatus of the present invention, a desired plasma potential can be controlled by applying an appropriate bias voltage to the bias applying means singly or in a superimposed manner. Thus, a functional deposition film of high quality and few defects can be continuously and efficiently formed with high yield and good reproducibility.

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

In the apparatus of the present invention, the pressure outside the film forming chamber may be in a depressurized state or a pressurized state. However, when the band-shaped member is greatly deformed by a pressure difference from the film forming chamber, an appropriate auxiliary structure is used. A material may be provided in the film forming chamber.
As the auxiliary structure material, it is desirable that the shape substantially the same as the side wall of the film forming chamber is formed by 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 structure material into close contact with the band-shaped member, and rotating or moving the auxiliary structure material in synchronization with the conveyance speed of the band-shaped member, a mesh pattern or the like applied to the auxiliary structure material is formed on the band-shaped member. It can also be formed.

As the material of the belt-shaped member suitably used in the apparatus of the present invention, a material having little deformation and distortion at a temperature required at the time of forming a functional deposited film by a microwave plasma CVD method and having a desired strength may be used. Preferably
Specifically, thin plates of metal such as stainless steel, aluminum and its alloys, iron and its alloys, copper and its alloys and their composites, and metal thin films of different materials on their surfaces by sputtering, vapor deposition, plating Those that have been subjected to a surface coating treatment. Also, polyimide, polyamide,
Heat-resistant resin sheets such as polyethylene terephthalate and epoxy, or composites of these with glass fiber, carbon fiber, boron fiber, metal fiber, etc. on the surface of a simple metal or alloy, and transparent conductive oxide (TCO)
And the like, which have been subjected to a conductive treatment by a method such as plating, vapor deposition, sputtering, or coating. In addition, SiO ₂ , Si ₃ N ₄ , Al ₂ O ₃ , AlN, and a material in which an insulating thin film such as the above-described heat-resistant resin is partially formed on the conductive treated surface of the belt-shaped member having the above-described configuration are used. You can also.

As long as the thickness of the band-shaped member is within a range that exhibits a strength that maintains a curved shape formed at the time of conveyance by the conveyance means, the thickness is preferably as thin as possible in consideration of cost, storage space, and the like. Is desirable. Specifically, the thickness is preferably 0.01 mm to 5 mm, more preferably 0.02 mm to 2 mm, and most preferably 0.05 mm to 1 mm.However, it is preferable to use a relatively thin metal plate to reduce the thickness. However, a desired strength is easily obtained. 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, it is preferably 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, at least one pair of support / transport rings having a desired curved shape is provided, and preferably both ends of the belt-shaped member are supported by the support / transport ring, and the belt is curved along the shape, and further, the belt-shaped member is bent. At least a pair of support / transport rollers provided in the longitudinal direction of the member as a curving start end forming means and a curving end end forming means are squeezed and bent into a substantially columnar shape. Giving a driving force to at least one of the rollers for
The belt-shaped member is transported in the longitudinal direction while maintaining the curved shape. In addition, as a method of supporting and transporting the belt-shaped member by the support / transport ring, only sliding friction may be used, or a process such as a sprocket hole may be performed on the belt-shaped member, and the support / transport ring may be used. Also, a so-called 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 to which feedback is applied. These mechanisms also have a great effect on controlling the film thickness in manufacturing a semiconductor device.

In addition, the supporting / transporting ring is disposed in the microwave plasma region, although the degree of the exposure is varied depending on the purpose. Therefore, a material that can withstand microwave plasma, that is, a material having excellent heat resistance, corrosion resistance, etc., is desirable. In addition, a deposited film adheres to the surface thereof, and the deposited film adheres during a long-time deposition operation. The film is peeled off and scattered, and adheres to the deposited film being formed, causing defects such as pinholes in the deposited film, and consequently the characteristics of the manufactured semiconductor device and the yield are reduced. Therefore, it is desirable that the deposited film be made of a material having a low adhesion coefficient or a material and surface shape capable of maintaining a strong adhesive force up to a considerable film thickness even if adhered. Specific materials include those processed using stainless steel, nickel, titanium, vanadium, tungsten, molybdenum, niobium and alloys thereof, or alumina, quartz, magnesia, zirconia, silicon nitride, boron nitride, nitrided on the surface thereof. Examples thereof include a material obtained by coating a ceramic material such as aluminum by a thermal spraying method, a vapor deposition method, a sputtering method, an ion plating method, a CVD method, or the like, or a material obtained by molding a single or composite ceramic material. The surface shape is appropriately selected in consideration of the stress of the film to be deposited, such as mirror finishing and unevenness processing.

The deposited film adhered to the support / transport ring is preferably removed before peeling, scattering, etc. occur, and a chemical or physical method such as wet etching after dry etching or decomposition in a vacuum or bead blasting is performed. Is desirably removed.

The support / transport roller is designed to have a larger area in contact with the belt-shaped member than the support / transport ring, and thus has a higher heat exchange rate with the belt-shaped member. Therefore, it is desirable to have a mechanism for appropriately adjusting the temperature so that the temperature of the belt-shaped member is not extremely increased or decreased by the supporting / transporting roller. However, the set temperatures of at least one pair of supporting / transporting rollers may be different. Furthermore,
The incorporation of a transport tension detecting mechanism for the belt-like member in the support / transport roller is also effective in keeping the transport speed constant.

Further, it is preferable that a crown mechanism is provided on the support / transport roller in order to prevent the belt-shaped member from bending, twisting, laterally displacing, and the like at the time of transport.

The curved shape formed in the present invention is formed in a columnar shape so as to 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, it is preferable to insert a substrate cover that covers a part of the side wall in order to control the thickness of the film deposited in the film forming chamber.

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, V, Cr, Cu, stainless steel, brass, nichrome, SnO ₂ , In ₂ O ₃ , ZnO, SnO ₂ -In ₂ O ₃ (ITO)
It is desirable to form a current extraction electrode by performing a surface treatment in advance by a method such as plating, vapor deposition, or sputtering on a so-called metal simple substance or alloy or a transparent conductive oxide (TCO). In addition, an insulating film may be partially formed for the purpose of facilitating the element isolation process.

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

Further, the surface property of the belt-shaped member may be a so-called smooth surface or a fine uneven surface. In the case of a 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 via 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, and the characteristics and the like are changed. In such a case, the initial state can be restored by removing the film deposited on the separation means by dry etching, wet etching, a mechanical method, or the like. In particular, dry etching is preferably used as a method for removing the deposited film while maintaining 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 separation means along the outer peripheral surface of the separation means,
It is also possible to employ a method of depositing and forming a deposited film on the surface of the sheet and discharging the film 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 a plasma and maintain it. It has a structure that can be used. Specifically, 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 having 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 cutoff frequency is used. It is preferable that the frequency is lower than the standard frequency, specifically, standard products such as JIS, EIAJ, IEC, JAN, and 2.
In-house standard for 45GHz, 96mm width with square cross-section inner diameter
X 27 mm height etc. can be mentioned.

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, a relatively stable discharge can be maintained 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 enhance 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, or 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 be grounded to the waveguide only at the connection part, and that the waveguide and the shutter means be 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 a ground 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.

In the apparatus of the present invention, the bias applying means provided for controlling the plasma potential is disposed so that at least a part thereof contacts plasma generated in the film forming chamber. Hereinafter, typical examples of the arrangement and the like will be specifically described with reference to the drawings, but the bias applying means in the device of the present invention is not limited to these.

FIGS. 13 (A) to 13 (D) show the device of the present invention shown in FIG. 1 in the cross-sectional schematic view shown in FIG. 5 (a).
A schematic side sectional view in the H 'direction is shown. In these drawings, only main components are shown.

The example shown in FIG. 13 (A) is a typical example in which the bias applying means also serves as the gas supply means. The belt-like member 1301 is grounded, and is conveyed while being maintained in a curved shape by the support / transport roller 1302. I have. Reference numeral 1303 denotes a bias applying tube also serving as a gas introducing tube, and a gas supply tube 1310 and an insulating joint.
Connected at 1309. Then, a bias voltage generated by a bias application power supply 1307 is applied to a bias application tube 1303 also serving as a gas introduction tube. As the bias application power supply 1307, in addition to a commercially available DC stabilized power supply, AC power supply, high-frequency power supply, and the like, a function generator is used to apply a bias voltage having various waveforms and frequencies. A power supply system for amplifying the waveform output by a precision power amplifier can be made by itself and used. It is preferable to constantly monitor the bias application voltage and the bias current value with a recorder or the like, and incorporate the data into a control circuit for improving the stability and reproducibility of the plasma and suppressing the occurrence of abnormal discharge. Is desirable.

The position at which the bias applying tube 1303 is disposed in the film forming chamber is not particularly limited as long as the bias applying tube 1303 is disposed in contact with the microwave plasma. In order to suppress this, it is desirable that the belt-like member 1301 is disposed at a distance of preferably 10 mm or more, more preferably 20 mm or more, from the inner surface.

Since the bias application tube 1303 also serves as a gas introduction tube, it is desirable that a hole or a slit is formed in the circumferential direction, particularly in the longitudinal direction, to uniformly discharge the source gas. Further, the tube diameter and the tube length are designed so as to secure a desired current density, but the surface area is preferably made small as long as the current density is secured. Thus, it is possible to suppress a decrease in the utilization efficiency of the raw material gas due to the formation of the deposited film on the surface, the separation of the deposited film, and an increase in the defect occurrence rate of the deposited film formed on the belt-like member due to the scattering. . Further, with this configuration, the decomposition efficiency of the raw material gas can be further improved.

The example shown in FIGS. 13 (B) and 13 (D) is a typical example in which the gas supply means and the bias applying means are provided independently of each other. In FIG. 13 (B), a bias rod 1304 is provided. One,
FIG. 13D shows the bias rod 1304 and the second bias rod 13.
Although an example in which 06 is provided is shown, another bias rod may be additionally provided if desired.

Reference numerals 1307 and 1308 denote bias application power supplies, which may have exactly the same specifications or different specifications so that independent bias voltages can be applied. A source gas is introduced into the film forming chamber through a gas introduction pipe 1305. It is preferable that each of the bias rod 1304 and the second bias rod is a rod-shaped or tubular rod made of a heat-resistant metal, for example, stainless steel, nickel, titanium, vanadium, niobium, tantalum, molybdenum, tungsten, or the like. By adopting a tubular structure, it is possible to flow a cooling medium through the tubular structure to suppress abnormal heat generation of the bias rod. The positions where these components are provided are almost the same as those in the case of the bias applying tube 1303.

The gas introduction tube 1305 is preferably made of a dielectric material in order to suppress occurrence of abnormal discharge and to form a uniform plasma potential. However, the gas introduction tube 1305 can be used without any problem even if it is conductive and grounded.

The example shown in FIG. 13 (C) is a typical example in which a bias voltage is applied to the belt-like member, and a power supply 1307 for bias application is connected to the belt-like member 1301. The gas introduction pipe 1305 is formed of a conductive member and is grounded.
Note that the gas introduction tube 1305 may be made of a dielectric material, and a ground electrode may be separately provided. The position where the gas introduction pipe 1305 is provided is not particularly limited as long as it is in contact with the plasma.

In the apparatus of the present invention, the film formation chamber and / or the isolation container are separated from a vacuum container having another film formation means and a vacuum atmosphere, and the belt-shaped member is continuously conveyed through the inside thereof. The gas gate means is suitably used for the above. In the apparatus of the present invention, it is desirable that the inside of the film forming chamber and / or the isolation vessel is maintained at a low pressure necessary for operation near the minimum value of the modified Paschen curve. In many cases, the pressure in another vacuum vessel to be connected is at least substantially equal to or higher than the pressure. Therefore, it is necessary for the gas gate means to have a capability of preventing the mutually used deposition film forming source gases from diffusing due to a pressure difference generated between the containers. Thus, the basic concept can employ the gas gating means disclosed in U.S. Pat. No. 4,438,723, but its capabilities need to be further improved. Specifically, up to 10 ⁶
It is necessary to be able to withstand a pressure difference of about twice, and as an exhaust pump, an oil diffusion pump, a turbo molecular pump, a mechanical booster pump, or the like having a large exhaust capacity is suitably used. In addition, the cross-sectional shape of the gas gate is a slit shape or a shape similar thereto, and the dimensions thereof are calculated and designed using a general conductance calculation formula together with the overall length and the exhaust capacity of the exhaust pump to be used. . Further, it is preferable to use a gate gas in combination to enhance the separation ability, for example, a rare gas such as Ar, He, Ne, Kr, Xe, or Rn or H
_{And a second} dilution gas for forming a deposited film. The flow rate of the gate gas is appropriately determined depending on the conductance of the entire gas gate, the capacity of the exhaust pump to be used, and the like. However, a pressure gradient generally shown in FIGS. 6 (a) and 6 (b) may be formed. In FIG. 6 (a), since there is a point where the pressure becomes maximum substantially at the center of the gas gate, the gate gas flows from the center of the gas gate to the vacuum vessel side on both sides, and in FIG. Since there is a point 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, the deposition film forming means disposed in another vacuum vessel connected to the isolation vessel by the gas gate means includes RF plasma CVD, sputtering and reactive sputtering, and ion plating. Means for realizing a method used for forming a so-called functional deposited film, such as a printing method, a photo CVD method, a thermal CVD method, a MOCVD method, an MBE method, and an HR-CVD method. And, of course, it is also possible to connect the means of the microwave plasma CVD method of the present invention and similar microwave plasma CVD method, select an appropriate means for manufacturing a desired semiconductor device, and connect using the gas gate means. Is done.

The microwave frequency supplied from the microwave power supply used in the device of the present invention is preferably 2.45 GHz, which is preferably used for consumer use, but is relatively easily available even in other frequency bands. Anything can be used. In addition, in order to obtain a stable discharge, the oscillation mode is preferably a so-called continuous oscillation, and the ripple width thereof is preferably within 30%, more preferably within 10% in a used output region.

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

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

FIG. 12 (part 1) (i) to FIG. 12 (part 4) (x)
The figure shows a schematic view for explaining the outline of the band-shaped member processing chamber and the operation at the time of film formation of the band-shaped member and the like.

In FIG. 12, reference numeral 1201a denotes a band-shaped member processing chamber (A) provided on the feeding side of the band-shaped member, and 1201b denotes a band-shaped member processing chamber (B) provided on the winding side of the band-shaped substrate. Viton rollers 1207a, 1207b, cutting blade 1208
a, 1208b and welding jigs 1209a, 1209b are stored.

That is, FIG. 12 (part 1) (i) shows a state at the time of normal film formation, in which the belt-shaped member 1202 is moving in the direction of the arrow in the figure,
The roller 1207a, the cutting blade 1208a, and the welding jig 1209a do not contact the belt-shaped member 1202. Reference numeral 1210 denotes a connection means (gas gate) with a belt-shaped member storage container (not shown), and reference numeral 1211 denotes a connection means (gas gate) with a vacuum container (not shown).

FIG. 12 (part 1) and (ii) show a first step for exchanging a new band-shaped member after the film-forming step on one band of the band-shaped member is completed. First, stop the belt-shaped member 1202,
The roller 1207a is moved in the direction of the arrow from the position shown by the dotted line in the figure to be brought into close contact with the band member 1202 and the wall of the band member processing chamber 1201a. In this state, the band-shaped member storage container and the film forming chamber are air-tightly separated. Next, the cutting blade 1208a is operated in the direction of the arrow in the figure to cut the band-shaped member 1202. The cutting blade 1208a is made of any one of those that can be mechanically, electrically, and thermally cut into the band-shaped member 1202.

FIG. 12 (part 1) (iii) shows a state in which the strip-shaped member 1203 cut and separated is wound up to the strip-shaped member storage container side.

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

FIG. 12 (part 2) (iv) shows a process in which a new band-shaped member 1204 is fed in and connected to the band-shaped member 1202. The ends of the belt-shaped members 1204 and 1202 are brought into contact with each other and are welded and connected by a welding jig 1209a.

In FIG. 12 (part 2) and (v), the inside of the band-shaped member storage container (not shown) is evacuated, and after the pressure difference with the film forming chamber is sufficiently reduced, the roller 1207a is moved to the band-shaped member 1202 and the band-shaped member processing chamber. (A) shows a state in which the belt-like members 1202 and 1204 have been wound apart from the wall of 1201a.

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

FIG. 12 (part 3) (vi) shows a state at the time of normal film formation, but each jig is arranged substantially symmetrically as described in FIG. 12 (part 1) (i).

FIG. 12 (part 3) (vii) shows that after the film forming step on one roll of the band-shaped member is completed, this is taken out and replaced with an empty bobbin for winding the band-shaped member subjected to the next film forming process. The steps for performing the steps are shown.

First, the belt-shaped member 1202 is stopped, and the roller 1207b is moved in the direction of the arrow from the position indicated by the dotted line in the drawing, so that the belt-shaped member
1202 and the wall of the strip-shaped member processing chamber 1201b. In this state, the band-shaped member storage container and the film forming chamber are air-tightly separated.
Next, the cutting blade 1208b is operated in the direction of the arrow in the figure to cut the band-shaped member 1202. The cutting blade 1208b is made of any of those capable of mechanically, electrically, and thermally cutting the strip-shaped base 1202.

FIG. 12 (part 3) (viii) shows a state in which the strip-shaped member 1205 after the cut and separated film formation step is wound up toward the strip-shaped member storage container.

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

FIG. 12 (part 4) (ix) shows a step in which the preliminary winding band member 1206 attached to the new winding bobbin is fed in and connected to the band member 1202. The end portions of the prewinding belt-like member 1206 and the belt-like member 1202 are brought into contact with each other, and are connected by welding with a welding jig 1209b.

In FIG. 12 (part 4) (X), the inside of the band-shaped member storage container (not shown) is evacuated, and after the pressure difference with the film forming chamber is sufficiently reduced, the roller 1207b is moved to the band-shaped member 1202 and the band-shaped member processing. This shows a state in which the belt-shaped members 1202 and 1206 have been wound away from the wall of the chamber (B) 1201b.

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

As the material gas for forming the functional deposited film used in the method and the apparatus of the present invention, a hydride, a halide, an organometallic compound or the like of the constituent elements of the various semiconductor thin films described above is preferably used. Those that can be introduced in a state are selected and used.

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

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

The deposited film forming source gas or the like is provided with a gas introduction pipe or a gas introduction pipe having a single or a plurality of gas discharge holes at a tip end thereof disposed in a columnar film formation chamber formed by the belt-shaped member. The plasma is uniformly discharged from the bias tube serving as the column into the columnar film forming chamber and is converted into plasma by microwave energy to form a microwave plasma region. As the material constituting the gas introduction tube or the bias tube also serving as the gas introduction tube, those having the above-described function without being damaged in the microwave plasma are preferably used. Specifically, heat-resistant metals such as stainless steel, nickel, titanium, niobium, tantalum, tungsten, vanadium, molybdenum, etc. and those obtained by spraying these on ceramics such as alumina, silicon nitride, quartz, etc., 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 deposited film forming source gas introduced into the columnar film forming chamber from the gas introduction pipe is partially or entirely decomposed to generate a deposited film forming precursor,
Although a deposited film is formed, an undecomposed raw material gas or a gas having a different composition due to decomposition needs to be quickly exhausted to the outside of the columnar film forming chamber. However, if the area of the exhaust hole is made unnecessarily large, microwave energy leaks from the exhaust hole, causing instability of plasma or adversely affecting other electronic devices, the human body, and the like. . Therefore, it is desirable to provide exhaust holes by the following three methods. (I) A mesh or a punching board is provided on both sides of a ring provided at the end of the support / transport ring used for bending the belt-shaped member, and gas can be exhausted therefrom. Prevent leaks. However, it is preferable that the hole diameter of the mesh or the punching board is a size that causes a pressure difference between the inside and outside of the columnar film formation chamber and prevents microwave leakage. Specifically, the maximum diameter of each hole is preferably not more than 1/2 wavelength of the microwave used, more preferably not more than 1/4 wavelength, and the aperture ratio is preferably not more than 80%, more preferably. Is 60%
It is desirable that: Of course, at this time, air is simultaneously exhausted from a gap between the bending start end and the bending end end of the band-shaped member or a gap (slit) formed between the bending start end and the bending end end of the band-shaped member and the outer peripheral wall of the separating means. However, in order to prevent microwave leakage, the interval is preferably not more than 1/2 wavelength, more preferably not more than / 4 wavelength of the wavelength of microwave used. (Ii) Thin plates are provided on both sides of the support / transport ring used for bending the belt-shaped member, which is provided at the end, so that gas exhaust and microwave leakage therefrom do not occur. Then, gas is exhausted only from a gap between the bending start end and the bending end end of the band-shaped member or a gap (slit) formed between the curved end of the band-shaped member and the outer peripheral wall of the separating means. However, in order to prevent microwave leakage, the interval is preferably not more than 1/2 wavelength of the microwave used, more preferably not more than 1/4 wavelength. (Iii) (i) on both sides of the support / transport ring
And any one of the mesh or punching board and the thin plate described in (ii). That is, a method combining both (i) and (ii) can be mentioned. It is desirable that both the mesh, the punching board, and the thin plate have been subjected to the same material and surface treatment as the support / transport ring.

(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.

Reference numeral 101 denotes a belt-shaped member, and rollers 102 and 103 for supporting and transporting.
The sheet is conveyed in the direction of the arrow in the figure while maintaining a cylindrically curved shape by the supporting and conveying rings 104 and 105. Ten
Reference numeral 6107 denotes a temperature control mechanism for heating or cooling the belt-shaped member 101.

Reference numeral 108 denotes a microwave applicator,
Is separated from the microwave plasma region 113. Reference numeral 110 denotes a metal tube for preventing microwave leakage, 111 denotes a metal mesh for preventing microwave leakage, and 112 denotes a bias applying tube also serving as a gas introducing tube. Reference numerals 114 and 115 denote microwave meshes for preventing microwave leakage. The microwave plasma region 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 evacuated by a not-shown exhaust device through a gap between the separation means 109 and the transport rollers 102 and 103 and / or the wire meshes 114 and 115 for preventing microwave leakage.

A bias voltage generated by a bias application power supply 118 is applied to a bias application tube 112 also serving as a gas introduction tube via a conducting wire 119. Further, the bias applying tube 112 also serving as a gas introduction tube is insulated and separated from the gas supply tube 117 via an insulating joint.

Although the belt-shaped member 101 is grounded, it is preferable that the belt-shaped member is uniformly grounded over substantially the entire side wall portion of the columnar film forming chamber, and the supporting and transporting rollers 102 and 103, the supporting and transporting rings 104 and 105, and the It is desirable to be grounded via an electric brush (not shown) or the like that comes into contact with the side wall.

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.

In this example of the apparatus, the bias applying means having the configuration shown in FIG. 13 (A) is provided. Of course, any of the bias applying means shown in FIGS. 13 (B) to 13 (D) can be used. An application unit may be provided.

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 separating means 1 protruding through both walls of the isolation container 400.
09 is fixed. Fixing flanges 401 and 402 are isolated containers 4
It is preferably made of a suitable corrosion-resistant material such as stainless steel as in the case of 00, and is preferably detachable from the isolation container 400. The fixing flange 401 is attached to the connection flange 404. Connecting flange 404
Is attached directly to the side wall of the isolation container 400. Here, an opening 405 which is substantially 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. The ground finger 410 keeps electrical contact with the fixing flange 401. 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 occurs at high power levels.

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 chalk 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.

The arrangement here has at least two proximity points on the outer peripheral surface of the separating means 109, and a hole 2 formed in the circular waveguide 202.
The figure shows a case where it is 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 support / transport ring 104 (105)
When the width of the film is as small as possible with respect to the width of the belt-like member to be used, the effective utilization rate of the film deposited on the substrate is increased. This is because a film to be deposited on the substrate is deposited on the support / transport ring 104 (105).

In addition, 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 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 this surface 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 are desirably a means that can perform both heating and / or cooling. 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 distances L ₁ and L ₂ at the close point between the outer peripheral surface of the separation means 109 and the strip-shaped member 101 are at least in order to prevent leakage of microwave energy therefrom and to confine the microwave plasma region within a curved shape. It is preferable that the wavelength is set to be shorter than half the wavelength of the emitted microwave. However, the interval L ₃ between the bending start end and the curved terminal end of the belt-shaped member 101 is microwave energy emitted is efficiently radiated to the belt-shaped member 101 is formed a curved shape in the area from the microwave applicator 201 Therefore, it is desirable that the wavelength is set to be longer than / 4 of the wavelength of the emitted microwave.

Since microwave energy radiated from the aperture 208 is emitted in the direction substantially perpendicular to the side facing the pores 208 have directivity, its radial direction oriented substantially perpendicular to at least towards the spacing L ₃ Is preferred.

The bias application tube 112 also serving as a gas introduction tube is provided with a hole having an arrangement and a hole diameter for substantially uniformly discharging gas. Further, the position where the bias applying tube also serving as the gas introducing tube is installed in the curved shape is not particularly limited as long as it is within a range in contact with the plasma.

In this example of the apparatus, the bias applying means having the configuration shown in FIG. 13 (A) is provided. Of course, any of the bias applying means shown in FIGS. 13 (B) to 13 (D) can be used. An application unit may be provided.

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 prevent standing waves from hitting, but there is no particular problem even if it is sealed. With this structure, microwave energy can be radiated from the entire surface of the hole 304, but the concentration of the microwave energy is maximized particularly at the end of the hole closer to the microwave power supply. Therefore, the connecting portion 305
By using at least one shutter 306 attached to the circular waveguide 302, the degree of concentration can be adjusted. Preferred shapes of the shutter 306 include a strip shape, a trapezoid shape, and a shape in which one side of the strip or trapezoid is cut out in a half-moon shape or the like as shown in FIGS. 3 (b) to 3 (d).

The connecting portion 305 includes a groove 307 opened on the side of the shutter 306 near 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. This is 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 shutter 306 and the waveguide 302, this becomes an arc contact.

In this example of the apparatus, the bias applying means having the configuration shown in FIG. 13 (A) is provided. Of course, any of the bias applying means shown in FIGS. 13 (B) to 13 (D) can be used. An application unit may be provided.

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 thereof has a wavelength of the microwave used. It is preferable that the wavelength is not more than 1/2 wavelength, more preferably not more than 1/4 wavelength, and of such a degree that the permeation 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, it is desirable that the bias applying tube 112 also serving as a gas introducing tube is disposed so as to be in contact with microwave plasma generated in a region surrounded by the separating means 109 and the band-shaped member 101.

In this example of the apparatus, the bias applying means having the configuration shown in FIG. 13 (A) is provided. Of course, any of the bias applying means shown in FIGS. 13 (B) to 13 (D) can be used. An application unit may be provided.

Apparatus Examples 6 and 7 In Apparatus Examples 4 and 5, the microwave applicator 201 was used.
Was changed to the microwave applicator 301 used in the device example 2, and the same configuration 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.

In this example of the apparatus, the bias applying means having the configuration shown in FIG. 13 (A) is provided. Of course, any of the bias applying means shown in FIGS. 13 (B) to 13 (D) can be used. An application unit may be provided.

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 that also serve to adjust the tension and position the belt-shaped member. Reference numerals 712 and 713 denote temperature adjusting mechanisms used for preheating or cooling the belt-like member. 707,
708,709 are throttle valves for adjusting the displacement, 710,711,7
Reference numeral 20 denotes an exhaust pipe, each of which is connected to an exhaust pump (not shown). 714 and 715 are pressure gauges, 716 and 717 are gate gas introduction pipes, 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 isolation container 400-a, 400-b for forming a deposited film by D is connected to both sides, so that a stacked device can be manufactured.

In this example of the apparatus, the isolation container 400 is provided with a bias applying means having the configuration shown in FIG. 13A, and the isolation containers 400a and 400b are provided with the bias application means having the configuration shown in FIG. Although the example in which the bias applying means is provided is shown, each of the isolation containers may include any of the bias applying means having the configurations shown in FIGS. 13 (A) to 13 (D).

In the drawing, 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, 805,806,807,808
, 809, 810, 811, 812 are gate gas exhaust pipes, respectively.

Apparatus Examples 14 and 15 In Apparatus Examples 12 and 13, the microwave applicator 20 was used.
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 20 was used.
A similar configuration can be mentioned except that a slow-wave circuit type microwave applicator (not shown) is used.

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.

In this example of the apparatus, FIG.
13B, but of course, any of the configurations shown in FIGS. 13B to 13D may be provided.

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 908 are halogen lamps for heating the substrate, 909 and 910 are anode electrodes, and 9
11,912 is an exhaust pipe.

Other Apparatus Examples For example, in Apparatus Example 13, an isolation container 40 for forming a deposited film is used.
A device in which the various microwave applicators described above are combined and mounted in 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 may be mentioned, for example, devices in which the arrangement of the band-shaped 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.

An example of a semiconductor device suitably manufactured by the method and apparatus of the present invention is a solar cell. FIGS. 11A to 11D schematically show typical examples of the layer structure.

In the example shown in FIG. 11A, the lower electrode 11 is placed on a support 1101.
02, a photovoltaic element 1100 in which an n-type semiconductor layer 1103, an i-type semiconductor layer 1104, a p-type semiconductor layer 1105, a transparent electrode 1106, and a collecting electrode 1107 are formed in this order. In this photovoltaic element, it is assumed that light enters from the transparent electrode 1106 side.

In the example shown in FIG. 11B, a transparent electrode 1106, a p-type semiconductor layer 1105, an i-type semiconductor layer 1104, and an n-type
This is a photovoltaic element 1100 'in which a mold semiconductor layer 1103 and a lower electrode 1102 are formed in this order. In this photovoltaic element, it is assumed that light enters from the light-transmitting support 1101 side.

The example shown in FIG. 11 (C) is formed by laminating two pin junction type photovoltaic elements 1111 and 1112 using two kinds of semiconductor layers having different band gaps and / or layer thicknesses as i-layers. This is a so-called tandem photovoltaic element 1113. Reference numeral 1101 denotes a support, and the lower electrode 1102, the n-type semiconductor layer 1103, the i-type semiconductor layer 1104, the p-type semiconductor layer 1105, the n-type semiconductor layer 1108,
An i-type semiconductor layer 1109, a p-type semiconductor layer 1110, a transparent electrode 1106, and a current collecting electrode 1107 are stacked in this order, and it is assumed that light is incident from the transparent electrode 1106 side in the present photovoltaic element. .

The example shown in FIG. 11 (D) is configured by stacking three pin junction type photovoltaic elements 1120, 1121, and 1123 using three types of semiconductor layers having different band gaps and / or layer thicknesses as i-layers. This is a so-called triple type photovoltaic element 1124.
Reference numeral 1101 denotes a support, and the lower electrode 1102, the n-type semiconductor layer 110
3, i-type semiconductor layer 1104, p-type semiconductor layer 1105, n-type semiconductor layer 1114, i-type semiconductor layer 1115, p-type semiconductor layer 1116, n-type semiconductor layer 1117, i-type semiconductor layer 1118, p-type semiconductor layer 1119, A transparent electrode 1106 and a current collecting electrode 1107 are laminated and formed in this order,
In this photovoltaic element, it is assumed that light is incident from the transparent electrode 1106 side.

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 1101 used in the present invention is preferably made of a material that is flexible and capable of forming a curved shape, and may be either conductive or electrically insulating. Good. Further, they may be light-transmitting or non-light-transmitting, but are light-transmitting when light is incident from the support 1101 side. 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 1102 used in the present invention, the surface to which the light for photovoltaic generation is irradiated differs depending on whether or not the material of the support 1101 is translucent (for example, When the support 1101 is made of a non-translucent material such as a metal, light for photovoltaic generation is irradiated from the transparent electrode 1106 side as shown in FIG. 11A.) Location is different.

Specifically, in the case of a layer configuration as shown in FIGS. 11A, 11C and 11D, it is provided between the support 1101 and the n-type semiconductor layer 1103. However, when the support 1101 is conductive, the support can also serve as the lower electrode. However, if the sheet resistance is high even if the support 1101 is conductive, the electrode may be used as a low-resistance electrode for extracting current, or for the purpose of increasing the reflectivity on the support surface and making effective use of incident light. 1102 may be installed.

In the case of FIG. 11B, a light-transmitting support 1101 is used, and light is incident from the support 1101 side. Therefore, for the purpose of current extraction and light reflection at the electrode, A lower electrode 1102 is provided to face the support 1101 with the semiconductor layer interposed therebetween.

When an electrically insulating material is used as the support 1101, a lower electrode 1102 is provided between the support 1101 and the n-type semiconductor layer 1103 as an electrode for extracting current.

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

Although not shown in the drawing, a diffusion preventing layer such as conductive zinc oxide may be provided between the lower electrode 1102 and the n-type semiconductor layer 1103. The effect of the diffusion prevention layer is not only to prevent the metal element constituting the electrode 1102 from diffusing into the n-type semiconductor layer, but also to provide a slight resistance value so that the lower electrode provided with the semiconductor layer interposed therebetween. The effect of preventing short-circuiting caused by a defect such as a pinhole between the 1102 and the transparent electrode 1106, and the effect of generating multiple interference by the thin film and confining the incident light within the photovoltaic element are mentioned. it can.

(Ii) Upper electrode (transparent electrode) The transparent electrode 1106 used in the present invention has a light transmittance of 85% or more in order to efficiently absorb light from the sun or a white fluorescent lamp into the semiconductor layer. The sheet resistance is desirably 100Ω or less so that the output of the photovoltaic element does not become a resistance component. As a material having such properties, Sn
Metal oxides such as O ₂ , In ₂ O ₃ , ZnO, CdO, Cd ₂ SnO ₄ , ITO (In ₂ O ₃ + SnO ₂ ), and metals such as Au, Al, Cu etc. Metal thin film and the like. The transparent electrode is laminated on the p-type semiconductor layer 1105 in FIGS. 11 (A), (C) and (D), and is laminated on the substrate 1101 in FIG. 11 (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 heating evaporation method, a sputtering method, a spray method, or the like can be used, and is appropriately selected as desired.

(Iii) Current collecting electrode The current collecting electrode 1107 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 of the 1106. Ag, Cr, Ni, Al, Ag, Au, Ti, P
Examples include thin films of metals such as t, Cu, Mo, W, and the like, or alloys thereof. These thin films can be stacked and used.
The shape and area of the semiconductor layer are appropriately designed so that the amount of light incident on the semiconductor layer is sufficiently ensured.

For example, it is desirable that the shape is uniformly spread 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 Semiconductor materials constituting the i-type semiconductor layer suitably used in the present photovoltaic element include A-Si: H, A-Si: F, A
−Si: H: F, A−SiC: H, A−SiC: F, A−SiC: H: F, A−SiGe: H, A
−SiGe: F, A−SiGe: H: F, poly−Si: H, poly−Si: F, poly−S
In addition to so-called Group IV and Group IV alloy semiconductor materials such as i: H: F,
So-called compound semiconductor materials of the I-VI group and the III-V group are exemplified.

P-type semiconductor layer and n-type semiconductor layer P-type or n-type preferably used in the present photovoltaic device
As the semiconductor material constituting the semiconductor layer, the above-mentioned i
It can be obtained by doping a valence electron controlling agent into a semiconductor material constituting the type semiconductor layer.

(Production example)

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

Production Example 1 The continuous microwave plasma CVD apparatus (FIG. 7) shown in Apparatus Example 12 was used to continuously deposit an amorphous silicon film. 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 having a length of 100 m and a thickness of 0.2 mm) is set, and the band-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. Table 19 shows conditions such as the curved shape of the belt-shaped member.

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 started to evacuate to about 10 ⁻³ Torr. While maintaining the surface temperature of the charging member 101 at 250 ° C., the pressure was reduced to 5 × 10 ⁻⁶ Torr or less by an oil diffusion pump (not shown) (HS-32 manufactured by Varian).

At the time when the degassing was sufficiently performed, SiH ₄ 550 sccm and S were supplied from the bias applying tube 112 also serving as a nickel gas introducing tube.
iF ₄ 8 sccm, introducing H ₂ 40 sccm, the film formation chamber by adjusting the opening degree of the throttle valve attached to the oil diffusion pump
The pressure in 723 was kept at 85 mTorr. At this time, isolation container 40
The pressure inside 0 was 1.5 mTorr. When the pressure is stable,
A microwave having an effective power of 1.7 kW was emitted from the applicator 301 from a microwave power supply (not shown). Immediately, the introduced source gas is turned into plasma to form a microwave plasma region, and the microwave plasma region is connected to wire meshes 501, 501 'attached to the side surfaces of the transfer rings 104, 105.
(1 mm wire diameter, 5 mm spacing) did not leak to the vacuum vessel side, and no microwave leakage was detected.

Therefore, a DC voltage of +90 V from the bias application power supply 118 is applied via the conducting wire 119 to the bias application tube 1 serving also as a gas introduction tube.
When applied to 12, a bias current of 7.5 A flowed, and the brightness of the plasma increased slightly visually.

Therefore, the supporting / transporting rollers 102, 103 and the supporting / transporting rings 104, 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. Even when the transfer was started, the plasma was stable, and the bias voltage and the current did not change.

The gas gates 721, 722 have gate gas inlet pipes 716, 7
Flow 50sccm H ₂ gas as the gate gas from 17, the exhaust hole 71
Air was exhausted from an oil diffusion pump (not shown) from 8, 718, and the internal pressure of the gas gate was controlled to 1 mTorr.

A deposited film was formed continuously for 30 minutes after the start of transport. 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%, and the deposition rate was 86 ° / sec on average.
Also, cut out a part, it was measured infrared absorption spectrum by a reflection method using FT-IR (Perkin Elmer 1720X), observed absorption at 2000 cm ^-1 and 630cm ^-1 a-Si: H : Absorption pattern peculiar to the F film. Furthermore, when the crystallinity of the film was evaluated by RHEED (JEM-100SX, manufactured by JEOL Ltd.), it was found that the film was halo and amorphous. The hydrogen content in the film was determined using a hydrogen in metal analyzer (EMGA-1100, manufactured by HORIBA, Ltd.).
Met.

Further, the amorphous silicon film deposited and formed on the belt-shaped member was mechanically peeled over an area of about 5 cm ² and its volume was measured. Subsequently, the spin density was measured with an ESR device (JES-RE2X, manufactured by JEOL Ltd.). 2.8 × 10 ¹⁵ spi
ns / cm ³ , indicating that the film had few defects.

In addition, a sample of 1 cm × 1 cm was arbitrarily cut out from the other part of the band-shaped member at five places and set on a reactive sputtering apparatus (in-house product) to set a 1500 mm ITO (on the surface where the amorphous silicon film was deposited) In ₂ O ₃ + SnO ₂ ) films were deposited. Then, this sample piece was converted to CPM (Constant Photocurre
nt Method) device (manufactured in-house), light was incident from the ITO film side, and the inclination of the Urbach Tail was measured. As a result, it was found that the film was 49 ± 1 meV and had few defects. Was.

Production Example 2 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 vessel 400 was evacuated to 5 × 10 ⁻⁶ Torr or less, and then the gas was used as a gas introduction pipe. SiH ₄ 160sccm, GeH ₄ 13
0 sccm, SiF ₄ 5 sccm, H ₂ 25 sccm were introduced, the internal pressure of the film forming chamber 723 was maintained at 14.5 mTorr, the microwave applicator was No. 11, and the microwave power was 0.95 kW. Under the conditions, an amorphous silicon germanium film was continuously deposited.

In addition, a DC voltage of +50 V from a bias applying power supply 118 is applied via a conducting wire 119 to a bias applying tube 112 serving also as a gas introducing tube.
, A bias current of 7.1 A flowed, and the brightness of the plasma was slightly increased visually.

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 40Å / sec.

Also, cut out a part, it was measured infrared absorption spectrum by a reflection method using FT-IR (Perkin Elmer 1720X), 2000cm ^-1, 1880cm ^-1 and 630 cm ^-1
The absorption pattern was unique to the a-SiGe: H: F film. Furthermore, when the crystallinity of the film was evaluated by RHEED (JEM-100SX, manufactured by JEOL Ltd.), it was found that the film was halo and amorphous. In addition, hydrogen analyzer in metal (EMGA-11
(00, manufactured by Horiba, Ltd.), the amount of hydrogen in the film was determined to be 15 ± 2 atomic%.

Further, the amorphous silicon germanium film deposited and formed on the band-shaped member was mechanically peeled over an area of about 5 cm ² and its volume was measured. Subsequently, an ESR device (JES
-RE2X, manufactured by JEOL Ltd.)
4.4 × 10 ¹⁵ spins / cm ³ , which proved that the film had few defects.

In addition, five 1 cm × 1 cm sample pieces were arbitrarily cut out from the other part of the above-mentioned band-shaped member and set on a reactive sputtering device (in-house product) to set a 1500 mm ITO on the surface on which the amorphous silicon germanium film was deposited. (In ₂ O ₃ + Sn
O ₂ ) film deposited. Then, this sample piece was converted to CPM (Constan
t Photocurrent Method) device (manufactured in-house), light is incident from the ITO film side, and Urbak hem (Urbac
When the inclination of h Tail) was measured, it was 53 ± 1 meV, and it was found that the film had few defects.

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 vessel 400 was evacuated to 5 × 10 ⁻⁶ Torr or less, and then the gas introduction pipe was also used. From bias application tube 112, SiH ₄ 260sccm, CH ₄ 38s
ccm, SiF ₄ 5sccm, introducing H ₂ 80 sccm, except for holding the inner pressure of the film forming chamber 723 to 24mTorr was continuously deposition of amorphous silicon carbide film by the same deposition film forming conditions.

In addition, a DC voltage of +60 V from a bias applying power supply 119 is applied via a conducting wire 120 to a bias applying tube 113 serving also as a gas introducing tube.
, A bias current of 7.3 A flowed, and the brightness of the plasma was slightly increased visually.

After completion of this production example and other production examples, the belt-shaped member 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 average deposition rate was 43Å / sec.

Further, a part thereof was cut out, and the infrared absorption spectrum was measured by a reflection method using FT-IR (1720X manufactured by Perkin-Elmer Co., Ltd.). As a result, 2080 cm ⁻¹ , 1250 cm ⁻¹ , and 960 c
m ^-1, a-SiC observed absorption at 777cm ^-1 and 660cm ^-1: H: F
The absorption pattern was unique to the film. In addition, RHEED (JEM-
When the crystallinity of the film was evaluated using 100SX (manufactured by JEOL Ltd.), it was found that the film was halo and amorphous. The amount of hydrogen in the film was determined using a hydrogen-in-metal analyzer (EMGA-1100, manufactured by Horiba, Ltd.) to be 13 ± 2 atomic%.

Further, the amorphous silicon carbide film deposited and formed on the belt-shaped member was mechanically peeled over an area of about 5 cm ² , and its volume was measured. Subsequently, an ESR device (JES-
RE2X, manufactured by JEOL Ltd.)
It was 9 × 10 ¹⁵ spins / cm ³ , which proved that the film had few defects.

In addition, five 1 cm × 1 cm sample pieces were arbitrarily cut out from the other part of the above-mentioned band-shaped member and set in a reactive sputtering apparatus (in-house product) to set a 1500 mm-long surface on the surface on which the amorphous silicon carbide film was deposited. ITO (In ₂ O ₃ + Sn
O ₂ ) film deposited. Then, this sample piece was converted to CPM (Constan
t Photocurrent Method) device (manufactured in-house), light is incident from the ITO film side, and Urbak hem (Urbac
When the inclination of h Tail) was measured, it was 55 ± 1 meV, and it was found that the film had few defects.

Production Example 4 Following the deposition film forming process performed in Production Example 1, the introduction of the used raw material gas was stopped, and the internal pressure of the isolation container 400 was evacuated to 5 × 10 ⁻⁶ Torr or less, and then the gas introduction pipe was also used. From the bias applying tube 112, SiH ₄ 270sccm, BF ₃ (30
00ppm H ₂ dilution) 55 sccm, introducing SiF ₄ 48sccm, H ₂ 45sccm, maintains the internal pressure of the film forming chamber 723 to 19MTorr, microwave applicators and No.3, similar except that the microwave power 2.8kW The p-type microcrystalline silicon film was continuously deposited under the conditions for forming the deposited film described above.

In addition, a DC voltage of +125 V from a bias application power supply 119 is applied via a conducting wire 120 to a bias application tube 1 serving also as a gas introduction tube.
When a voltage of 13 was applied, a bias current of 8.6 A flowed, and the brightness of the plasma increased slightly visually.

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.

Also, cut out a part, it was measured infrared absorption spectrum by a reflection method using FT-IR (Perkin Elmer 1720X), observed absorption at 2100 cm ^-1 and 630cm ^-1 μC-Si: H : Absorption pattern peculiar to the F film.
Further, when the crystallinity of the film was evaluated by RHEED (JEM-100SX, manufactured by JEOL Ltd.), it was found that the film was ring-shaped and non-oriented polycrystalline. In addition, hydrogen analyzer in metal (EMGA-
(1100, manufactured by Horiba, Ltd.), the amount of hydrogen in the film was determined to be 4 ± 1 atomic%.

Furthermore, for the film deposited and formed on the belt-shaped member, 5 mm
5 × 5 mm specimens are arbitrarily cut out, and the surface condition is ultra-high resolution, low acceleration FE-SEM (Hitachi S-900 type)
As a result, the surface of the film was smooth and almost no occurrence of abnormal projections was observed.

Production Example 5 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.
From 5, SiH ₄ 380 sccm, PH ₃ (1% H ₂ dilution) 32 sccm, SiF ₄
5 sccm, H ₂ 25 sccm was introduced, and the internal pressure of the deposition chamber 723 was set to 11 mTor.
r, the n-type amorphous silicon film was continuously deposited under the same deposition film forming conditions except that the microwave power was set to 1.1 kW.

In addition, a DC voltage of +90 V from a bias application power supply 118 is applied via a conducting wire 119 to a bias application tube 112 serving also as a gas introduction tube.
, A bias current of 7.1 A flowed, and the brightness of the plasma was slightly increased visually.

After completion of this production example and other production examples, the belt-shaped member 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 average deposition rate was 60 ° / sec.

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

Furthermore, for the film deposited and formed on the belt-shaped member, 5 mm
5 × 5 mm specimens are arbitrarily cut out, and the surface condition is ultra-high resolution, low acceleration FE-SEM (Hitachi S-900 type)
As a result, the surface of the film was smooth and almost no occurrence of abnormal projections was observed.

Production Example 6 In Production Example 1, instead of the SUS430BA band-shaped substrate,
2 μm of an Al film was vapor-deposited on the surface on which the deposited film was formed (a part of which was formed with a comb gap having a width of 70 μm and a length of 10 mm every 20 cm in the width and longitudinal directions) PET (polyethylene) Terephthalate) band-shaped substrate (width 60 cm x length 10)
0 m × 0.8 mm in thickness), and an amorphous silicon film was continuously deposited in exactly the same operation except that the substrate surface temperature was 210 ° C.

In addition, a DC voltage of +90 V from a bias application power supply 118 is applied via a conducting wire 119 to a bias application tube 112 serving also as a gas introduction tube.
, A bias current of 7.0 A flowed, and the brightness of the plasma was slightly increased visually.

The substrate was taken out after cooling, and the film thickness distribution was measured within the width direction and the longitudinal direction to be within 5%. The deposition rate was 84 ° / sec on average. In addition, a part of it was cut out and FT-IR (1720X manufactured by Perkin-Elmer)
The use, by measurement of infrared absorption spectrum by the reference transmission method, observed absorption at 2000 cm ^-1 and ^{630cm -1, a-Si: H} : was absorbing pattern specific to F film. The amount of hydrogen in the film was determined from the absorption attributable to Si-H near 2000 cm ^-1 to be 23 ± 2 atomic%.

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

In addition, 20 of the gap electrodes formed in advance are used.
A portion was randomly cut out, and a photocurrent value under AM-1 light (100 mW / cm ² ) irradiation and a dark current value in darkness were measured using HP4140B for each, and the light conductivity σp (S / c
m) and the dark conductivity σd (S / cm) were determined to be (5.5 ± 0.5) × 10 ⁻⁵ S / cm and (1.5 ± 0.5) × 10 ⁻¹¹ S, respectively.
/ cm range.

In addition, this sample piece was used for CPM (Constant Photocurrent Met
hod) The device was set in a device (in-house manufactured device), the light was incident from the ITO film side, and the inclination of the Urbach Tail was measured. As a result, it was found that the film was 51 ± 1 meV and had few defects. Was.

Production Examples 7 to 11 The deposited films were formed under the same conditions as those of Production Examples 1 to 5, except that the bias application voltage was changed to the condition shown in Table 20, and under the same plasma generation conditions.

The evaluation of the formed deposited film is shown in Table 20 by combining the results of performing the same method as in Production Examples 1 to 5. In any case, abnormal discharge did not occur and plasma was not generated. A stable film having good characteristics was obtained.

Production Examples 12 to 16 In the production conditions of Production Examples 1 to 5, except that the bias application voltage applied to the second bias rod was changed to the condition shown in Table 21, the same operation and plasma generation conditions were used. A deposited film was formed. The bias was applied as shown in FIG. 13 (D), and +30 V was applied to the first bias rod in each case.

The results of the evaluation of the deposited film formed were performed in the same manner as in Production Examples 1 to 5, and the results are shown in Table 21. In any case, abnormal discharge did not occur and plasma was not generated. A stable film having good characteristics was obtained.

Production Example 17 In this production example, a Schottky junction diode having the layer configuration shown in the schematic sectional view of FIG. 10 was produced using the apparatus shown in FIG.

Here, 1001 is a substrate, 1002 is a lower electrode, 1003 is an n ⁺ type semiconductor layer, 1004 is a non-doped semiconductor layer, 1005 is a metal layer,
1006 and 1007 are current extracting terminals.

First, a strip member 101 made of SUS430BA similar to that used in Production Example 1 was set in a continuous sputtering apparatus, and a Cr thin film of 1500Å was deposited using a Cr (99.98%) electrode as a target to form a lower electrode 1002. did.

Subsequently, the strip-shaped member 101 was set on the delivery bobbin 703 in the vacuum vessel 701 of the continuous deposition film forming apparatus of FIG. 7 shown in the apparatus example 12, and the surface on which the Cr thin film was deposited faced downward. In this state, the end was wound around the winding bobbin 704 in the vacuum container 702 via the isolation container 400, and the tension was adjusted so that there was no slack.

Note that the conditions such as the curved shape of the substrate in this manufacturing example
The microwave applicator was the same as that shown in Table 19, and the microwave applicator used was the No. 13 type similar to that of Production Example 1.

Thereafter, roughing and high vacuuming operations similar to those of Production Example 1 were performed by an exhaust pump (not shown) through the exhaust pipes 709, 710, and 711 of the respective vacuum vessels. At this time, the substrate surface temperature is 250 ° C
Are controlled by the temperature control mechanisms 106 and 107 so that

At the time when degassing was sufficiently performed, SiH ₄ 340 sccm, SiF ₄ 5 sccm, P
Introduce 55 sccm of H ₃ / H ₂ (1% H ₂ dilution) and 25 sccm of H ₂ , adjust the opening of the throttle valve 709, and reduce the internal pressure of the film forming chamber 723.
When the pressure was stabilized at 11 mTorr, a microwave of 1.8 kW was immediately emitted from the applicator 301 from a microwave power supply (not shown). When a DC bias voltage of +80 V was applied at the same time that the plasma was generated, 7.8
A bias current flowed. The transfer was started when the plasma was stabilized, and a deposition operation was performed for 5 minutes while transferring from the left side to the right side in the figure at a transfer speed of 53 cm / min. Thus, an n ⁺ type a-Si: H: F film as the n ⁺ semiconductor layer 1003 is formed on the lower electrode 1002.

During this time the gas gates 721 and 722 flow 50sccm of H ₂ as gate gas was evacuated by an exhaust pump (not shown) through the exhaust hole 718, the gas gate pressure was controlled to be 2 mTorr.

Stop supplying microwaves and introducing raw material gas,
After the conveyance of the band-shaped member 101 is stopped, the internal pressure of the isolation container 400 is reduced to 5
After evacuating to × 10 ⁻⁶ Torr or less, SiH ₄ 360 sccm, SiF ₄ 10
Introducing sccm and H ₂ 45sccm, adjusting the opening of the throttle valve 709, maintaining the internal pressure of the film formation chamber 723 at 7.5 mTorr, and immediately after the pressure was stabilized, 1.7 kW from a microwave power supply (not shown) Microwaves were emitted from the applicator 301. When a DC bias voltage of +80 V was applied at the same time as the plasma was generated, a bias current of 6.8 A flowed. When the plasma is stabilized, transfer starts, and 56
The stacking operation was performed for 5.2 minutes while transporting reversely from right to left in the figure at a transport speed of cm / min. This gives n
^{On the +} type a-Si: H: F film, an a-Si: H: F film as a non-doped semiconductor layer 1004 is laminated.

After completion of all the deposition operations, the supply of the microwave and the supply of the raw material gas were stopped, the conveyance of the belt-like member 101 was stopped, the residual gas in the isolation container 400 was sufficiently exhausted, and the belt-like member was taken out after cooling.

A permalloy mask having a diameter of 5 mm was randomly adhered to ten portions of the strip-shaped member, and an Au thin film as the metal layer 1005 was vapor-deposited at 80 ° by an electron beam vapor deposition method. Subsequently, the current extraction terminals 1006 and 1007 were bonded using a wire bonder, and diode characteristics were evaluated using HP4140B.

As a result, good diode characteristics were obtained with a rectification ratio of about 6 digits at a diode factor n = 1.08 ± 0.05 and ± 1V.

Production Example 18 In this production example, a pin-type photovoltaic element having a layer configuration shown in the schematic sectional view of FIG.
It was manufactured using the continuous deposition film forming apparatus shown in the figure.

The photovoltaic element has a lower electrode 1102, an n-type semiconductor layer 1103, an i-type semiconductor layer 1104, a p-type semiconductor layer 1105,
This is a photovoltaic element 1100 in which a transparent electrode 1106 and a current collecting electrode 1107 are formed in this order. In this photovoltaic element, it is assumed that light enters from the transparent electrode 1106 side.

First, the same PET band-shaped member 101 as used in Production Example 6 was used.
Is set in a continuous sputtering apparatus, and a 1000 μg Ag thin film is used as a target using an Ag (99.99%) electrode as a target.
A ZnO thin film having a thickness of m was sputter deposited to form a lower electrode 1102.

Subsequently, the band-shaped member 101 on which the lower electrode 1002 is formed
Was set in the continuous deposition film forming apparatus shown in FIG. 8 in the same manner as in Production Example 17. Isolation container 40 at this time
Table 22 shows conditions such as the curved shape of the substrate within 0.

In the isolation containers 400-a and 400-b, the n-type a-Si: H: F film and the p ⁺ -type μc-
A Si: H: F film was formed.

First, microwave plasma is generated in a vacuum vessel, and when the discharge or the like is stabilized, the belt-shaped member 101 is transported at a speed of 47 c.
transported from left to right at m / min
An n, i, p-type semiconductor layer was formed by lamination.

After laminating and forming a semiconductor layer over the entire length of the belt-shaped member 101, take out after cooling, and further, with a continuous modularization device
A solar cell module of 40 cm × 80 cm was continuously produced.

For the fabricated solar cell module, AM1.5 (100mW
/ cm ²⁾ was subjected to characteristic evaluation under optical irradiation, obtained over 8.6% in photoelectric conversion efficiency had more variation in the characteristics among the modules accommodated within 5%.

In addition, the rate of change of the photoelectric conversion efficiency from the initial value after 500 hours of continuous irradiation with AM1.5 (100 mW / cm ² ) light was measured.
It fell within 9.5%.

Furthermore, when compared with the case of a solar cell module formed without applying a bias voltage, the defect occurrence rate due to a short circuit or the like was improved by 20% or more.

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

Production Example 19 In this production example, an a-SiGe: H: F film was used instead of the a-Si: H: F film as the i-type semiconductor layer in the pin-type photovoltaic element produced in Production Example 18. Here is an example.

The formation of the a-SiGe: H: F film was performed under the same film forming conditions as in Production Example 2 except that the transfer speed was 50 cm / min, the bias voltage was square wave (1 kHz), and 180 V _PP . The other semiconductor layer formation and modularization steps were performed in the same manner and in the same manner as in Production Example 18, to produce a solar cell module.

For the fabricated solar cell module, AM1.5 (100mW
/ cm ²⁾ was subjected to characteristic evaluation under optical irradiation, obtained over 7.6% in photoelectric conversion efficiency had more variation in the characteristics among the modules accommodated within 5%.

In addition, the rate of change of the photoelectric conversion efficiency from the initial value after 500 hours of continuous irradiation with AM1.5 (100 mW / cm ² ) light was measured.
It fell within 9.5%.

Furthermore, when compared with the case of a solar cell module formed without applying a bias voltage, the defect occurrence rate due to a short circuit or the like was improved by 20% or more.

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

Production Example 20 In this production example, in the pin-type photovoltaic element produced in Production Example 18, an a-SiC: H: F film was used instead of the a-Si: H: F film as the i-type semiconductor layer. Here is an example.

The a-SiC: H: F film was formed by the same operation and method as in Production Example 3, except that the transfer speed was 43 cm / min, the bias voltage was a sine wave (500 Hz), and 170 V _PP . The other semiconductor layer formation and modularization steps were performed in the same manner and in the same manner as in Production Example 18, to produce a solar cell module.

For the fabricated solar cell module, AM1.5 (100mW
/ cm ²⁾ was subjected to characteristic evaluation under optical irradiation, obtained over 6.7% in photoelectric conversion efficiency had more variation in the characteristics among the modules accommodated within 5%.

In addition, the rate of change of the photoelectric conversion efficiency from the initial value after 500 hours of continuous irradiation with AM1.5 (100 mW / cm ² ) light was measured.
It fell within 9.5%.

Furthermore, when compared with the case of a solar cell module formed without applying a bias voltage, the defect occurrence rate due to a short circuit or the like was improved by 20% or more.

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

Production Example 21 In this production example, a photovoltaic device having a layer configuration shown in FIG. 11 (C) was produced. At the time of production, in the apparatus shown in FIG. 8, isolation containers 400-a ', 400', 400-b 'having the same configuration as the isolation containers 400-a, 400, 400-b are further connected in this order via a gas gate. (Not shown).

The band-shaped member was made of the same material and processed as used in Production Example 1, and the lower element 1111 was manufactured in Production Example 19 and the upper element 1112 was manufactured in the same layer as that manufactured in Production Example 18. Table 24 shows the conditions for forming the deposited film of each semiconductor layer. The module forming step was performed by the same operation and method as in Production Example 18 to produce a solar cell module.

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

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

Furthermore, when compared with the case of a solar cell module formed without applying a bias voltage, the defect occurrence rate due to a short circuit or the like was improved by 20% or more.

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

Production Example 22 In this production example, a photovoltaic element having a layer configuration shown in FIG. 11 (C) was produced. At the time of fabrication, in the apparatus shown in FIG. 8, the isolation containers having the same configuration as the isolation containers 400-a, 400, 400-b are further connected to the isolation containers 400-a ', 400', 400-b 'in this order via the gas gate. A device (not shown) was used.

The band-shaped member used was the same material and processed as used in Production Example 1, and the lower element 1111 was the same as that produced in Production Example 20 and the upper element 1112 was the same layer as produced in Production Example 20. Table 25 shows the conditions for forming the deposited film of each semiconductor layer. The module forming step was performed by the same operation and method as in Production Example 18 to produce a solar cell module.

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

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%.

Furthermore, when compared with the case of a solar cell module formed without applying a bias voltage, the defect occurrence rate due to a short circuit or the like was improved by 20% or more.

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

Production Example 23 In this production example, a photovoltaic device having a layer configuration shown in FIG. 11D was produced. In the production, the isolation containers 400-a ', 400', 400-b ', 400-a ", 400", 40 ", 40 having the same configuration as the isolation containers 400-a, 400, 400-b in the apparatus shown in FIG.
A device (not shown) in which O-b ″ was further connected in this order via a gas gate was used.

As the belt-shaped member, the same material and treatment as used in Production Example 1 was used. The lower element 1120 was Production Example 19, the intermediate element 1121 was Production Example 18, and the upper element 1123 was Production Example 20. Table 26 shows the conditions for forming the deposited film of each semiconductor layer. The module forming step was performed by the same operation and method as in Production Example 18 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 10.7% or more was obtained, and the variation in characteristics between modules was within 5%.

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

Furthermore, when compared with the case of a solar cell module formed without applying a bias voltage, the defect occurrence rate due to a short circuit or the like was improved by 20% or more.

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

[Summary of Effects of the Invention] According to the method of the present invention, a belt-like member constituting a side wall of a film forming space is continuously moved, and a micro member is formed in a width direction of the band-like member constituting a side wall of the film forming space. Microwave applicator means for radiating or transmitting microwave energy uniformly with directivity in one direction perpendicular to the traveling direction of the wave is provided, and by confining the microwave plasma in the film forming space, It is possible to form a functional deposited film having a large area continuously and with good uniformity.

Further, according to the method of the present invention, by appropriately controlling the plasma potential, a high-quality functional deposition film having desired characteristics and few defects can be continuously and efficiently formed at a high yield. .

According to the method and apparatus of the present invention, the stability and reproducibility of the microwave plasma are improved by confining the microwave plasma in the film formation space and controlling the plasma potential, and the utilization efficiency of the source gas for forming the deposited film is improved. Can be dramatically increased. Further, by continuously transporting the belt-shaped member, a curved film, a length, and a transport speed are variously changed so that a deposited film having an arbitrary film thickness is continuously deposited with good uniformity over a large area. Can be formed.

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

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

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

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

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

[Brief description of the drawings]

FIG. 1 is a schematic diagram of a microwave plasma CVD apparatus of the present invention. 2 and 3 (a) to (d)
FIG. 2 is a schematic view of the microwave applicator means of the present invention. FIG. 4 is a schematic cross-sectional view of the microwave plasma CVD apparatus of the present invention. FIG. 5 (a), (b)
FIG. 3 is a diagram schematically showing a side cross-sectional view of a belt-shaped member transport mechanism according to the present invention. FIG. 6 is a diagram schematically showing a pressure gradient of the gas gate means in the present invention. 7 to 9 show the continuous microwave plasma CVD of the present invention.
It is the whole schematic of an example of an apparatus. FIG. 10 is a schematic cross-sectional view of a Schottky junction diode manufactured in the present invention. FIGS. 11A to 11D are schematic cross-sectional views of a pin-type photovoltaic device (single, tandem, triple) manufactured in the present invention. FIGS. 12 (i) to (X) are views for explaining a method of processing a band-shaped member. FIG. 13 is a diagram showing a typical arrangement of bias applying means. FIG. 14 is a current-voltage characteristic diagram when a bias voltage is applied, obtained in an experimental example of the present invention. FIG. 15 is a diagram showing a change rate of a plasma potential when a bias voltage is applied, obtained in an experimental example of the present invention. 1 to 13, 101, 1301,..., A belt-shaped member, 102, 103, 1302,... A support / transport roller, 104, 105,.
… Temperature control mechanism, 108 …… Microwave applicator, 1
09: Separation means, 110, 416: Metal cylinder, 111: Wire mesh, 11
2,1303 …… Bias applying tube also serving as gas introduction tube, 113…
… Microwave plasma region, 114,115 …… Wire mesh for preventing microwave leakage, 116,1309 …… Insulating joint, 117,1310 ……
Gas supply pipe, 118, 1307, 1308… Power supply for bias application, 1
19 …… conductor, 201,301 …… microwave applicator, 2
02,302 …… Circular waveguide, 203 …… Terminal part, 204,205,206,2
07, 208, 304 ... hole, 303 ... open end, 305 ... connecting part, 30
6… Shutter, 307… Groove, 308… Fixing pin, 309
…… Insulator, 400… Isolated vessel, 401,402… Fixing flange, 403… Square, circular conversion waveguide, 404,411… Connection flange, 405,412 …… Opening, 406,407,413,414 ……
O-ring, 408, 415, cooling groove, 409, open end, 41
0,417 …… Finger for grounding, 418 …… Connecting plate, 419…
… Exhaust hole, 420 …… Connection flange, 421 …… Square waveguide,
501,501 ', 502,502'… wire mesh, 701,702,901,902… vacuum container, 703… delivery bobbin, 704… winding bobbin, 705,706 …… conveyor roller, 707,708,709…
Throttle valve, 710,711,718,719,720 …… Exhaust vent, 7
12,713 …… Temperature adjustment mechanism, 714,715 …… Pressure gauge, 716,71
7,805,806,807,808 …… Gate gas inlet pipe, 721,722,80
1,802,803,804 …… Gas gate, 723… Deposition chamber, 809,81
0,811,812… Gate gas exhaust pipe, 903,904… Cathode electrode, 905,906… Gas introduction pipe, 907,908 …… Halogen lamp, 909,910… Anode electrode, 911,912 …… Exhaust pipe,
1001,1101 ... Support, 1002,1102 ... Lower electrode, 1003,1
103, 1108, 1114, 1117 ... n-type semiconductor layer, 1004, 1104, 110
9,1115,1118 ... i-type semiconductor layer, 1005 ... metal layer, 1006,
1007 …… Current extraction terminal, 1100,1100 ′, 1111,1112,
1120,1121,1123 ... pin junction type photovoltaic element, 1105,111
0, 1116, 1119: p-type semiconductor layer, 1106: upper electrode, 110
7… current collecting electrode, 1113… tandem photovoltaic element, 112
4 Triple photovoltaic element, 1201a Band processing chamber (A), 1201b Band processing chamber (B), 1202, 120
3,1204,1205,1206 ... Band member, 1207a, 1207b ... Roller, 1208a, 1208b ... Cutting blade, 1209a, 1209b ... Welding jig, 1210,1211,1212,1213 ... Connection means, 1304, 1306 ……
Bias rod, 1305 …… Gas inlet tube.

Claims (48)

(57) [Claims] 1. A belt-like member is moved in a longitudinal direction, a film-forming space having a side wall on the belt-like member is formed in the middle of the belt-like member, and a deposition film is formed in the formed film-forming space via a gas supply means. The microwave energy is introduced into the film forming space by microwave applicator means for introducing a source gas for use and simultaneously radiating or transmitting the microwave energy uniformly in one direction perpendicular to the traveling direction of the microwave. The side wall exposed to the microwave plasma is generated by radiating or transmitting the microwave plasma toward the belt-like member in the film formation space to control the plasma potential of the microwave plasma. Microwave plasma CV, wherein a deposited film is formed on said strip-shaped member
Method of forming deposited film by D method. 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 method according to claim 1, wherein said plasma potential is controlled via bias means separated from said strip-shaped member. 6. The bias applying means is disposed so that at least a part thereof is in contact with the microwave plasma.
The method according to claim 5, wherein a bias voltage is applied to the bias applying unit. 7. The deposited film forming method according to claim 6, wherein at least a part of said bias applying means in contact with said microwave plasma is subjected to a conductive treatment. 8. The method according to claim 6, wherein the bias voltage is DC, pulsating, or AC. 9. The method according to claim 6, wherein said bias applying means also functions as said gas supply means. 10. The method according to claim 6, wherein said bias applying means is provided separately from said gas supply means. 11. The method according to claim 10, wherein said bias applying means comprises one or a plurality of bias rods. 12. The method according to claim 1, wherein the plasma potential is controlled by a bias potential applied to the belt-shaped member. 13. The deposition film forming method according to claim 12, wherein said gas supply means has a ground potential, and at least a part thereof is disposed so as to be in contact with said microwave plasma. 14. The deposition film forming method according to claim 13, wherein at least a part of said gas supply means in contact with said microwave plasma is subjected to a conductive treatment. 15. A 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 to and from 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. 3. 16. As long as the separation means is not contacted,
16. The deposited film forming method according to claim 15, wherein the microwave applicator is disposed close to and substantially parallel to a width direction of the band-shaped member, and radiates or transmits microwave energy into the film forming space. . 17. The method according to claim 16, wherein the microwave applicator radiates or transmits uniform microwave energy having substantially the same length as the band-shaped member. 18. The microwave applicator means comprising:
18. The deposition film forming method according to claim 17, wherein the deposition film is separated from microwave plasma generated in the film formation space via the separation unit. 19. The method according to claim 1, wherein microwave energy radiated or transmitted into the film formation space is prevented from leaking outside the film formation space. 20. The method according to claim 1, wherein a surface of the belt-shaped member exposed to the microwave plasma is subjected to at least a conductive treatment. 21. A deposition film forming apparatus for moving a belt-like member in a longitudinal direction and forming a deposition film on said belt-like member in the middle of said belt-like member. Is formed in the middle of the longitudinal movement from the feeding mechanism to the winding mechanism by a set of rollers arranged in parallel with each other with a space, and forms a film forming space in which the band-shaped member functions as a wall. Means for forming a film-forming space for supporting the band-shaped member, the microwave being directed toward the band-shaped member arranged in the film-forming space with directivity in one direction perpendicular to the traveling direction of the microwave. In order to generate microwave plasma in the film forming space by introducing energy, the microwave applicator means connected to the film forming space, the microwave applicator means generated from the microwave plasma generated in the film forming space. Separation means for separating the preclicator means, exhaust means for exhausting the inside of the film formation space, gas supply means for introducing a deposition film forming source gas into the film formation space, plasma of the microwave plasma A bias applying means for applying a bias voltage for controlling a potential, a temperature controlling means for heating or cooling the strip-shaped member, and a bias applying means for controlling a plasma potential of the microwave plasma. A deposited film forming apparatus. 22. The deposited film forming apparatus according to claim 21, wherein said film forming space forming means comprises a pair of said rollers and a supporting and conveying ring disposed between said rollers. 23. 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. 22. The deposited film forming apparatus according to claim 21, wherein the film forming space is provided between the bending start end forming unit and the bending end end forming unit. 24. The roller set has at least one pair of support / transport rollers, the rollers constituting a curved portion forming means, and the curved portion forming means having a support / transport ring. 3. The deposited film forming apparatus according to item 1. 25. The deposited film forming apparatus according to claim 21, wherein said bias applying means is provided separately from said belt-shaped member. 26. The deposited film forming apparatus according to claim 25, wherein at least a part of said bias applying means is disposed so as to be in contact with said microwave plasma. 27. A conductive treatment is applied to a portion of said bias means which is in contact with said microwave plasma.
3. The deposited film forming apparatus according to item 1. 28. The deposited film forming apparatus according to claim 26, further comprising a bias voltage supply unit for supplying said bias voltage, wherein said bias voltage supply unit generates a DC, pulsating or AC voltage. 29. An apparatus according to claim 26, wherein said bias applying means is a part of a gas supply means. 30. The deposited film forming apparatus according to claim 26, wherein said bias applying means is provided separately from said gas supply means. 31. The deposited film forming apparatus according to claim 30, wherein said bias applying means has a plurality of bias rods. 32. The deposited film forming apparatus according to claim 30, wherein said bias applying means has one bias rod. 33. An apparatus according to claim 21, wherein said bias applying means also functions as a belt-like member. 34. The deposited film forming apparatus according to claim 21, wherein said gas supply means is grounded, and at least a part of said gas supply means is arranged so as to be in contact with said band microwave plasma. 35. The separating means is disposed substantially parallel to a gap left between the bending start end forming means and the bending end forming means, and is disposed outside the film forming chamber. 24. The deposited film forming apparatus according to claim 23. 36. The method according to claim 21, wherein the separation means is protruded from one of the side surfaces of the film formation space into the film formation chamber so as to be substantially parallel to a width direction of the band-shaped member. Deposition film forming equipment. 37. The separating means is substantially cylindrical.
22. The deposited film forming apparatus according to 21. 38. An apparatus according to claim 21, wherein said separation means is substantially semi-cylindrical. 39. The microwave applicator means comprising:
38. The deposition film forming apparatus according to claim 37, 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. 40. The deposited film forming apparatus according to claim 21, wherein said separating means is provided with a cooling means. 41. The deposited film forming apparatus according to claim 40, wherein said cooling means is an air flow flowing along an inner peripheral surface of said separating means. 42. 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.
38. The deposition film forming apparatus according to 37. 43. 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. 22. The deposited film forming apparatus according to claim 21, wherein a substantially rectangular hole is formed in order to provide directivity in a direction and uniformly radiate. 44. The deposited film forming apparatus according to claim 43, wherein at least one of said rectangular holes is formed on one surface of said waveguide, and microwaves are radiated from said holes. 45. The deposition film forming apparatus according to claim 43, wherein said rectangular holes are arranged at intervals in a longitudinal direction of said waveguide. 46. The deposited film forming apparatus according to claim 44, wherein said rectangular hole is formed as a rectangle provided over the entire space corresponding to the film formation space and larger than one wavelength of microwave. 47. The deposited film forming apparatus according to claim 46, further comprising shutter means corresponding to said rectangular hole. 48. The deposited film forming apparatus according to claim 21, wherein said microwave includes an evanescent microwave.