JPH0992849A - Formation of photovoltaic device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To restrain surface oxidation by providing an intermediate layer made of zinc oxide between a support and a reflection layer, depositing the reflection layer at a predetermined support temperature, then cooling the support down to a predetermined or lower temperature, and depositing a reflection increment layer at a predetermined support temperature to make the state of surface irregularity of the reflective layer appropriate for exhibiting high light confinement effect. SOLUTION: A support 100 is carried into a vacuum carrier chamber and the back side of the support 100 is heated in contact with a support heater, thus forming an intermediate layer 199 of oxide on the surface of the support 100. Then, the temperature of the support is set to 200-500 deg.C and an Ar plasma is generated, thus forming an optical reflective layer 101 made mainly of Ag. The temperature of the support is lowered not to exceed 100 deg.C in a support cooling gas atmosphere. Further, the temperature of the support is raised to 200-400 deg.C and an Ar plasma is generated, thus forming a surface reflection increment layer 102 of oxide made mainly of zinc oxide on the surface of the Ag optical reflective layer 101. Thus, surface oxidation of the reflective layer 101 may be restrained and high reflectance on the reflective layer 101 may be maintained.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a method for forming a photovoltaic device. More specifically, the photoelectric conversion efficiency can be improved, film peeling under high temperature and high humidity can be prevented, work efficiency is high, peeling at bent parts can be prevented, shunt resistance is low, and in cutting when modularizing. The present invention relates to a method for forming a photovoltaic element capable of preventing peeling.

[0002]

2. Description of the Related Art In conventional photovoltaic elements, in order to effectively use the light applied to the photovoltaic element, various measures have been taken in the reflection layer and the reflection increasing layer. For example, in "Photovoltaic device and method for manufacturing the same" described in JP-A-4-218977, a reflective layer has a discontinuous metal layer having irregularities and a continuous metal layer having a uniform layer thickness on the metal layer. Attempts to deposit a metal layer to improve the reflection by the metal layer have been disclosed. However, in order to improve the photoelectric conversion efficiency of the photovoltaic element, further improvement in reflectance has been desired.

Further, in the conventional photovoltaic element, there is a problem in the adhesion between the reflection layer and the reflection increasing layer. In particular, when the photovoltaic element was used for a long time under high temperature and high humidity, the problem tended to be remarkable. Similarly, the adhesiveness between the support and the reflective layer also has a problem when the photovoltaic element is used for a long time under high temperature and high humidity, and development of a method for improving it has been desired.

[0004]

DISCLOSURE OF THE INVENTION The present invention has a high reflectance due to the reflection layer and the reflection increasing layer, and has good adhesion between the reflection layer and the reflection increasing layer and between the support and the reflection layer. It is an object to provide a method for forming a photovoltaic element.

[0005]

A method of forming a photovoltaic element according to the present invention comprises a substrate having a reflective layer and a reflection increasing layer laminated on a support, containing silicon atoms, and having a crystalline structure. In a method for forming a photovoltaic element, a pin structure formed by laminating n-type, i-type, and p-type semiconductor layers, each of which is a non-single crystal, is repeatedly arranged at least once on a substrate. An intermediate layer made of zinc oxide is provided between the support and the reflective layer, and the reflective layer has a support temperature of 200 to 500 ° C.
In the step α, the step β in which the support temperature is cooled to 100 ° C. or lower after the step α, and the step γ in which the reflection increasing layer is deposited at the support temperature 200 to 400 ° C. after the step β. And having.

[0006] The main component of the reflection layer is silver, and the main component of the reflection enhancement layer is zinc oxide.

Further, it is desirable that the rate of decrease of the support temperature in the step β is 1 to 50 ° C./sec, and the rate of increase of the support temperature in the step γ is 10 to 100 ° C./sec. The gas for cooling the support is
It is preferably at least one gas selected from hydrogen gas, helium gas, and argon gas.

Further, it is desirable that the temperature of the support when depositing the intermediate layer is 30 to 500 ° C.

[0009]

[Action]

(Claim 1) In the invention according to claim 1, a step α in which an intermediate layer made of zinc oxide is provided between the support and the reflective layer, and the reflective layer is deposited at a support temperature of 200 to 500 ° C.
And by including a step β of cooling the support temperature to 100 ° C. or lower after the step α and a step γ of depositing the reflection increasing layer at a support temperature of 200 to 400 ° C. after the step β. The surface irregularities of the reflective layer made of metal can be formed into a surface state that sufficiently exerts the light confining effect,
Moreover, surface oxidation of the reflective layer can be suppressed to a small level.
As a result, the reflectance of the reflective layer can be kept high.

When the intermediate layer, the reflective layer and the reflection increasing layer are continuously deposited by the roll-to-roll method, oxygen atoms are deposited at a high temperature during the deposition of the reflection increasing layer made of oxide. There is a problem in that it diffuses to the surface of the formed reflective layer and excessively oxidizes the reflective layer. According to the invention of claim 1,
Such excessive oxidation of the reflective layer can be prevented.

Further, when forming a module in which a plurality of photovoltaic elements are integrated, an external force such as bending is applied to the photovoltaic element, which causes a problem such as peeling of the semiconductor layer from the support. there were. According to the invention of claim 1, such a problem can be solved.

As described above, the adhesion between the reflective layer and the reflection increasing layer can be improved by suppressing the oxidation of the surface of the reflective layer made of metal as much as possible. Further, the strain can be reduced by making the oxide layer thin. As a result, it is possible to reduce the stress of the reflection layer and the reflection increasing layer.

(2) In the invention according to claim 2, since the main component of the reflective layer is silver, the surface irregularities of the reflective layer have a discontinuous surface state having irregularities, which has a high light confinement effect. be able to.

(Claim 3) In the invention according to claim 3, since the main component of the reflection increasing layer is zinc oxide, the reflection increasing layer has a continuous surface state having a high reflection efficiency and a uniform layer thickness. can do.

(Claim 4) In the invention according to claim 4, the rate of decrease of the support temperature in the step β is 1 to 50 ° C.
/ Sec, when the temperature of the support decreases,
Thermal distortion due to temperature change of the support is suppressed, and peeling of the photovoltaic element from the support and increase in series resistance of the photovoltaic element can be suppressed.

(Claim 5) In the invention according to claim 5, the rate of rise of the support temperature in the step γ is 10 to 10
When it is 0 ° C./sec, when the temperature of the support increases, thermal strain due to the temperature change of the support is suppressed, and the photovoltaic element peels from the support and the series resistance of the photovoltaic element increases. Can be suppressed.

(Claim 6) In the invention according to claim 6, the support cooling gas in the step β is at least one gas selected from hydrogen gas, helium gas and argon gas, Oxidation of the surface of the reflective layer can be suppressed as much as possible, and the lowered temperature of the support can be maintained.

(Claim 7) In the invention according to claim 7, the temperature of the support when depositing the intermediate layer is 30 to 500.
By setting the temperature to be ° C, it is possible to improve the adhesion between the support and the reflective layer and at the same time suppress an increase in series resistance of the photovoltaic element.

[0019]

[Example embodiment]

(Photovoltaic Element) Examples of the photovoltaic element formed by using the method for forming a photovoltaic element of the present invention include those shown in FIGS. 1 and 2. 1 and 2 respectively show one pi
It shows the case of having an n structure and the case of having three pin structures. Hereinafter, description will be given with reference to FIGS. 1 and 2.

FIG. 1 is a schematic explanatory view of a photovoltaic device having one pin structure. As the photovoltaic element,
There are two cases: irradiation with light from the side opposite to the substrate and irradiation with light from the side of the substrate.

When light is irradiated from the side opposite to the substrate, the support 100, the intermediate layer 199, and the reflective layer 10 are arranged in this order from the bottom.
1, the substrate 190 including the reflection increasing layer 102, the first n-type layer (or p-type layer) 103, and n / i (or p /
i) buffer layer 151, first i-type layer 104, i / p
(Or n / i) buffer layer 161, first p-type layer (or n-type layer) 105, transparent electrode 112, collector electrode 1
It is composed of 13.

When irradiating light from the substrate side, 1
00 is a transparent support, 101 is a transparent conductive layer, and 10 is a transparent conductive layer.
2 is replaced with an antireflection layer, and 112 is replaced with a conductive layer also serving as a reflection layer.

FIG. 2 is a schematic explanatory view of a photovoltaic element having three pin structures. As the photovoltaic element,
There are two cases: irradiation with light from the side opposite to the substrate and irradiation with light from the side of the substrate.

When light is irradiated from the side opposite to the substrate, the support 200, the intermediate layer 299, and the reflective layer 20 are arranged in this order from the bottom.
1, a substrate 290 composed of the reflection increasing layer 202, a first n-type layer (or p-type layer) 203, a first n / i (or p / i) buffer layer 251, a first i-type layer 204, A first i / p (or n / i) buffer layer 261, a first
P-type layer (or n-type layer) 205, second n-type layer (or p-type layer) 206, second n / i (or p / i) buffer layer 252, second i-type layer 207, Second i / p
(Or n / i) buffer layer 262, second p-type layer (or n-type layer) 208, transparent electrode 212, current collecting electrode 2
It is composed of 13.

When irradiating light from the substrate side, 2
00 to the transparent support, 201 to the transparent conductive layer, 20
2 is replaced with an antireflection layer, and 212 is replaced with a conductive layer also serving as a reflection layer.

(Annealing Treatment) The annealing treatment in the present invention is performed, for example, near the interface between the p / i buffer layer and the p-type layer, near the interface between the n / i buffer layer and the n layer, or between the i layer and the p layer. And near the interface with the n-layer is effective. The flow rate of hydrogen gas, helium gas, or argon gas suitable for achieving the object of the present invention is appropriately optimized depending on the size of the processing chamber, but is preferably 100 to 10,000 sccm.

(Apparatus and Method for Forming Intermediate Layer, Reflective Layer, and Reflection Increasing Layer) Intermediate layer, reflective layer in the present invention,
Examples of the apparatus for forming the reflection increasing layer include those shown in FIGS. 3 and 6. FIG. 3 shows a multi-chamber separation type forming device,
FIG. 6 is a schematic cross-sectional view showing an example of a roll-to-roll type forming apparatus.

The multi-chamber separation type forming apparatus shown in FIG. 3 will be described below. The forming apparatus 300 includes a load lock chamber 301, transfer chambers 302 and 303, and an unload chamber 3
04, gate valves 306, 307, 308, heaters 310, 311 for heating the support, rails 31 for transporting the support.
3, light reflection layer deposition chamber 320, reflection increasing layer deposition chamber and intermediate layer deposition chamber 330, targets 321, 331, target electrodes 322, 332, gas introduction pipes 324, 334, sputtering power sources 325, 335, target shutter 32.
6, 336, a support 390 and the like.

However, a raw material gas supply device (not shown) is connected to the forming device shown in FIG. 3 through a gas introduction pipe. Ultra-high purity hydrogen gas cylinders, argon gas cylinders, and helium gas cylinders are all connected to the source gas cylinders. A metal for a reflective layer is placed on the target 321. The target 331 is provided with an oxide for the intermediate layer and / or the reflection enhancing layer.

A method of forming the intermediate layer, the reflection layer, and the reflection increasing layer using the multi-chamber separation type forming apparatus shown in FIG. 3 will be described below. Numbers in brackets indicate the formation procedure. (1) The support is ultrasonically washed with acetone and isopropanol and dried with warm air. The cleaned support is placed on the support transport rail 313 in the load chamber 301, and the interior of the load chamber 301 is evacuated to a pressure of about 1 × 10 ⁻⁵ Torr by a vacuum exhaust pump (not shown).

(2) The support is transferred to the transfer chamber 303, which is also evacuated by the vacuum exhaust pump (not shown), through the transfer chamber 302 which is evacuated by the vacuum exhaust pump (not shown) in advance. To do. (3) The back surface of the support 390 is provided with a heater 31 for heating the support.
1, the substrate is heated to a temperature of 30 to 500 ° C., and the inside of the deposition chamber 330 is evacuated by a vacuum exhaust pump (not shown) to a pressure of about 2 × 10 ⁻⁶ Torr.

(4) Ar gas is introduced at a desired flow rate through the gas introduction pipe 334, the pressure is adjusted to 6 mTorr by a conductance valve (not shown), a current is passed through the toroidal coil 333, and the sputtering power source 335 supplies 100 to 100 to 100 mPa.
DC power of 1000 V was applied to generate Ar plasma. (5) When the target shutter 336 is opened and the oxide intermediate layer 199 having a layer thickness of 1 to 100 nm is formed on the surface of the support, the target shutter 336 is closed to extinguish the plasma.

(6) The gate valve 307 is opened and conveyed into the deposition chamber 320. The back surface of the support 390 is brought into close contact with the support heating heater 310, and the temperature is 10 to 100 ° C. /
The temperature of the support is 200 to
The temperature is set to 500 ° C. and the deposition chamber 320 is evacuated by a vacuum exhaust pump (not shown) until the pressure reaches about 3 × 10 ⁻⁶ Torr.

(7) Ar gas is introduced from the gas introduction pipe 324 at a desired flow rate, adjusted by a conductance valve (not shown) so that the pressure becomes 1 to 30 mTorr, and an electric current is passed through the toroidal coil 323, and the sputtering power source 325 is used. 1
DC power of 00 to 1000 V was applied to generate Ar plasma. (8) The target shutter 326 is opened, and the Ag light reflection layer 10 having a layer thickness of 0.25 to 1 μm is formed on the surface of the stainless steel plate.
When 1 is formed, the target shutter 326 is closed to extinguish the plasma.

(9) After raising the heater 310 for heating the support and lowering the temperature of the support to 100 ° C. or less at a cooling rate of 1 to 50 ° C./sec in a He gas atmosphere as a gas for cooling the support, it is not shown in advance. The gate valve 307 is opened to carry the film into the transfer chamber 303 and the deposition chamber 330 which have been evacuated by the vacuum exhaust pump.

(10) The back surface of the support 390 is brought into close contact with the heater 311 for heating the support and heated with a temperature rising bead of 10 to 100 ° C./sec to set the temperature of the support to 200 to 400 ° C.
The interior of the deposition chamber 330 is evacuated by a vacuum exhaust pump (not shown) until the pressure reaches about 2 × 10 ⁻⁶ Torr. (11) Ar gas is introduced at a desired flow rate through the gas introduction pipe 334, the pressure is adjusted to 6 mTorr by a conductance valve (not shown), a current is applied to the toroidal coil 333, and the sputtering power source 335 supplies 100 to 1000 V.
DC power was applied to generate Ar plasma.

(12) The target shutter 336 is opened to form a layer thickness of 0.05 to 4 μm on the surface of the Ag light reflecting layer 101.
When the light reflection enhancing layer 102 of m oxide is formed, the target shutter 336 is closed to extinguish the plasma. (13) The heater 311 for heating the support is raised, and the cooling rate is 1 to 5 in a He gas atmosphere as a gas for cooling the support.
After lowering the support temperature to 100 ° C. or less at 0 ° C./sec, the gate valve 308 is opened and conveyed into the unload chamber 304 which has been evacuated by a vacuum exhaust pump (not shown) in advance. Thus, the intermediate layer, the light reflection layer and the light reflection increasing layer of the present invention are formed.

The roll-to-roll type forming apparatus shown in FIG. 6 will be described below. Forming device 600
Is a substrate delivery chamber 610 and a plurality of deposition chambers 611-6
14 and the substrate winding chamber 684 are sequentially arranged, and the separation passages 615, 616, 617, 618, 619 are provided between them.
Connected to each deposition chamber, each deposition chamber has an exhaust port, and the inside can be evacuated.

The method of forming the intermediate layer, the reflection layer and the reflection increasing layer using the roll-to-roll type forming apparatus shown in FIG. 6 will be described below. Belt-shaped support 62
1 passes through each of the above-described deposition chambers and each of the separation passages and is wound up from the substrate delivery chamber to the substrate winding chamber. At the same time, the gas can be introduced from the gas inlets of the deposition chambers and the separation passages, and the gas can be exhausted from the respective exhaust ports to form the respective layers.

An intermediate layer made of ZnO is formed in the deposition chamber 612, and a light reflection layer made of Ag is formed in the deposition chamber 613. In the deposition chamber 614, a reflection enhancing layer made of ZnO is formed. Halogen lamp heaters 640, 641, 642, 643 for heating the support from the back are installed inside each deposition chamber, and the temperature is raised or heated to a predetermined temperature in each deposition chamber. Further, the separation passages 617, 618, and 619 have the temperature lowering function of the present invention.

A DC magnetron sputtering method is performed in the deposition chamber 612, Ar gas is introduced from a gas inlet 632, and ZnO is used as a target 650. In the deposition chamber 613, DC magnetron sputtering method or RF
The magnetron sputtering method is used, and the gas inlet 6
Ar gas was introduced from 34, and Ag was introduced into the target 660.
Is used.

A DC magnetron sputtering method is performed in the deposition chamber 614, Ar gas is introduced from a gas inlet 636, and ZnO is used as a target 670. After forming the light reflection layer of the present invention under predetermined conditions, it is wound into the substrate winding chamber 614.

(Semiconductor Layer Forming Apparatus and Forming Method) As the semiconductor layer forming apparatus forming the pin structure in the present invention, those shown in FIGS. 4 and 5 can be mentioned. FIG. 4 is a schematic sectional view showing an example of a multi-chamber separation type forming apparatus, and FIG. 5 is an example of a roll-to-roll type forming apparatus.

The multi-chamber separation type forming apparatus shown in FIG. 4 will be described below. The forming apparatus 400 includes a load chamber 401 and transfer chambers 402, 403, 40.
4, unload chamber 405, gate valve 40
6, 407, 408, 409, substrate heating heater 41
0, 411, 412, a substrate transfer rail 413, an n-type layer (or p-type layer) deposition chamber 417, an i-type layer deposition chamber 418, a p-type layer (or n-type layer) deposition chamber 419, a plasma forming cup 420. , 421, power sources 422, 423, 424, microwave introduction window 425,
Waveguide 426, gas introduction pipes 429, 449, 469, valves 430, 431, 432, 433, 434, 44.
1, 442, 443, 444, 450, 451, 45
2,453,454,455,461,462,46
3, 464, 465, 470, 471, 472, 47
3, 474, 481, 482, 483, 484, mass flow controllers 436, 437, 438, 439,
456, 457, 458, 459, 460, 476, 4
77, 478, 479, a shutter 427, a bias rod 428, a substrate holder 490, an exhaust device (not shown), a microwave power source (not shown), a vacuum gauge (not shown), a controller (not shown), and the like.

The roll-to-roll type forming apparatus shown in FIG. 5 will be described below. Forming device 500
0 indicates the first n-type layer deposition chamber 502 between the load chamber 5010 for introducing the sheet substrate and the unload chamber 5150.
0, first RF-i layer (n / i) deposition chamber 5030, first
MW-i layer deposition chamber 5040, first RF-i layer (p /
i) deposition chamber 5050, first p-type layer deposition chamber 5060, second n-type layer deposition chamber 5070, second RF-i layer (n /
i) deposition chamber 5080, second MW-i layer deposition chamber 509
0, second RF-i layer (p / i) deposition chamber 5100, second
P-type layer deposition chamber 5110 and third n-type layer deposition chamber 512
0, the RF-i layer deposition chamber 5130, and the third p-type layer deposition chamber 5140 are connected together.

A gas gate (5201,
5202, 5203, 5204, 5205, 5206,
5207, 5208, 5209, 5210, 5211,
5212, 5213, 5214). Then, in each gas gate, gas supply pipes (5301, 5302, 5303, 5304, 53) to the gas gate are provided.
05, 5306, 5307, 5308, 5309, 53
10, 5311, 5312, 5313, 5314).

Load chamber 5010 and unload chamber 515
0 and each of the deposition chambers has exhaust pipes (5011, 502).
1, 5031, 5041, 5051, 5061, 507
1,5081, 5091, 5101, 5111, 512
1, 5131, 5141, 5151) and exhaust pumps (5012, 5022, 5032, 5042, 505).
2, 5062, 5072, 5082, 5092, 510
2, 5112, 5122, 5132, 5142, 515
2) is provided.

A source gas supply pipe (502) is provided in each deposition chamber.
5, 5035, 5045, 5055, 5065, 507
5, 5085, 5095, 5105, 5115, 512
5, 5135, 5145) via a mixing device (5
026, 5036, 5046, 5056, 5066, 5
076, 5086, 5096, 5106, 5116, 5
126, 5136, 5146) are provided.

Further, in each deposition chamber, RF supply coaxial cables (5023, 5033, 5043, 5053, 50) are provided.
63, 5073, 5083, 5093, 5103, 51
13, 5123, 5133, 5143) via a high frequency (hereinafter abbreviated as "RF") power supply (5024, 503)
4, 5044, 5054, 5064, 5074, 508
4, 5094, 5104, 5114, 5124, 513
4, 5144) are provided.

Load chamber 5010 and unload chamber 5150
A sheet feeding jig 5400 and a sheet winding jig 5402 are provided in each of the above. Sheet-shaped substrate 5401 delivered from the sheet delivery jig 5400
Are arranged so as to pass through the deposition chamber 13 and be wound up by the sheet winding jig 5402.

In addition, the MW-i layer deposition chamber (not shown) is connected to a coaxial cable for bias application, a power source, an exhaust gas treatment device, and the like.

(Support) As the material of the support in the present invention, there is little deformation and distortion at the temperature required for forming the deposited film, desired strength, and conductivity. desirable. Further, it is preferable to use a support which does not deteriorate the adhesion of the reflection layer or the reflection increasing layer to the support even when the hydrogen plasma treatment of the present invention is performed after depositing the reflection layer or the reflection increasing layer.

Specifically, for example, thin films of metals such as stainless steel, aluminum and its alloys, iron and its alloys, copper and its alloys, and composites thereof, and metal thin films of dissimilar materials on their surfaces and / or SiO ₂ , S
i ₃ N ₄ , Al ₂ O ₃ , AlN or other insulating thin film subjected to surface coating treatment by sputtering, vapor deposition, plating, etc., heat-resistant resin sheet of polyimide, polyamide, polyethylene terephthalate, epoxy, etc. Alternatively, the surface of a composite of these and glass fiber, carbon fiber, boron fiber, metal fiber or the like is subjected to a conductive treatment by a method such as plating, vapor deposition, sputtering or coating with a metal simple substance or an alloy, and a transparent conductive oxide or the like. Something you went to.

The thickness of the support is preferably as thin as possible in consideration of cost, storage space, etc., as long as the curved shape formed when the support is moved can maintain its strength. . Specifically, preferably 0.0
1 mm to 5 mm, more preferably 0.02 mm to 2
The optimum thickness is preferably 0.05 mm to 1 mm, but when a thin film of metal or the like is used, the desired strength can be easily obtained even if the thickness is relatively thin.

The width of the support is not particularly limited and is determined by the size of the vacuum container and the like. The length of the support is not particularly limited, and may be such a length that it can be wound into a roll or a longer one that is made longer by welding or the like. Absent.

In the present invention, the support is heated / cooled in a short time, but it is not preferable that the temperature distribution spreads in the lengthwise direction of the support. Therefore, it is desirable that the heat conduction in the moving direction of the support is small. In order for the body surface temperature to follow heating / cooling, it is preferable that the heat conduction is large in the thickness direction.

In order to reduce the heat conduction of the support in the moving direction and increase the heat conduction in the thickness direction, the thickness may be reduced. When the support is uniform, the value of (heat conduction) × (thickness) is preferably 1 × 10 ⁻¹ W / K or less, more preferably 5 × 10 ^−2.
It is preferably W / K or less.

(Intermediate Layer) As a material of the intermediate layer in the present invention, for example, zinc oxide is preferable. In particular, when stainless steel is used as the support and Ag is used as the reflective layer, zinc oxide as the intermediate layer greatly improves the adhesion. In the method for forming a photovoltaic element of the present invention, the thickness of the intermediate layer is
The range of 1 to 100 nm is preferable. The crystal grain size of the intermediate layer made of zinc oxide is preferably 100 nm or less. When the crystal grain size is larger than 100 nm, the adhesiveness is reduced. further,
The deposition rate of the intermediate layer of zinc oxide is 0.1 to 20 n.
m / sec is a preferable range.

The surface of the metal substrate is usually covered with oxide. Since zinc oxide used in the intermediate layer in the present invention is an oxide, it is considered that it has excellent adhesion to the oxide on the substrate surface.

Further, considering the adhesiveness to the reflecting layer made of metal, it is preferable that the content of oxygen atoms in the zinc oxide intermediate layer be distributed so as to decrease from the support side to the surface side. It is preferable.

(Reflective Layer) The material of the reflective layer in the present invention is, for example, Ag, Au, Pt, Ni, Cr, C.
Examples include metals such as u, Al, Ti, Zn, Mo, W, and alloys thereof. Thin films made of these metals are
For example, it is formed by vacuum evaporation, electron beam evaporation, sputtering or the like. In addition, care must be taken so that the formed metal thin film does not become a resistance component to the output of the photovoltaic element, and the sheet resistance value of the reflective layer is preferably 50Ω or less, more preferably 10Ω or less. Is desirable.

(Reflection Increasing Layer) The reflection increasing layer in the present invention has a light transmittance of 85% or more in order to efficiently absorb light from the sun, a white fluorescent lamp, or the like into each semiconductor layer. Desirably, the sheet resistance value is 1 so that the output of the photovoltaic element does not electrically become a resistance component.
It is desirable that the value is 00Ω or less. Examples of materials having such characteristics include SnO ₂ , In ₂ O ₃ , and Zn.
O, CdO, Cd ₂ SnO ₄ , ITO (In ₂ O ₃ + SnO
₂ ) and other metal oxides.

The reflection-increasing layer is p in a photovoltaic device.
To be laminated on the mold layer or n-type layer half, to form a photovoltaic element on the translucent support, and to irradiate light from the translucent support side, it is laminated on the support. Therefore, it is necessary to select those that have good mutual adhesion.

Further, it is preferable that the reflection increasing layer is deposited in a layer thickness suitable for the condition for increasing the reflection. As a method for producing the reflection increasing layer, for example, a resistance heating vapor deposition method, an electron beam heating vapor deposition method, a sputtering method, a spray method, or the like can be used, and it is appropriately selected as desired.

Further, the reflection increasing layer used in the forming method of the present invention is also preferably formed by a reactive sputtering method in which the metal constituting the oxide is targeted.

(I-Type Layer) In the present invention, the i-type layer is pi
The n-junction has a role of generating and transporting carriers for irradiation light. In particular, in a photovoltaic device using an amorphous semiconductor material made of IV group or IV group alloy, the i-type layer is in an important position.

A slightly p-type or n-type layer can be used as the i-type layer. Such a slightly p-type or n-type i-type layer is formed, for example, by adding hydrogen atoms (H, D) to an amorphous semiconductor material.
Alternatively, it is formed by containing a halogen atom (X). As shown below, the inclusions at this time have an important function.

Hydrogen atoms (H, D) or halogen atoms (X) contained in the i-type layer have a function of compensating for dangling bonds in the i-type layer, and the carrier in the i-type layer is a carrier. It improves the product of the mobility and the life of the. Also,
It has the effect of compensating for the interface states at the interfaces of the p-type layer / i-type layer and the n-type layer / i-type layer, and has the effect of improving the photovoltaic power, photocurrent and photoresponsiveness of the photovoltaic element. It is a thing. In this case, the optimum range of the content of hydrogen atoms and / or halogen atoms contained in the i-type layer is 1 to 40 at%.

Particularly, a preferable distribution form is one in which a large amount of hydrogen atoms and / or halogen atoms are distributed on each interface side of the p-type layer / i-type layer and the n-type layer / i-type layer. . In this case, the content of hydrogen atoms and / or halogen atoms near the interface is preferably in the range of 1.1 to 2 times the content in the bulk.
Furthermore, it is preferable that the content of hydrogen atoms and / or halogen atoms be changed corresponding to the content of silicon atoms.

When the photovoltaic element of the present invention has a plurality of pin structures, it is preferable that the i-type layers are laminated in order from the light incident side so that the band gap becomes smaller. Amorphous silicon or amorphous silicon carbide is used for the i-type layer having a relatively wide bandgap, and amorphous silicon germanium is used for the i-type semiconductor layer having a relatively narrow bandgap.

Amorphous silicon and amorphous silicon germanium are formed by an element for compensating for a dangling bond.
a-Si: H, a-Si: F, a-Si: H: F, a-
SiGe: H, a-SiGe: F, a-SiGe: H:
It is written as F or the like. When amorphous silicon germanium is used as the i-type layer, the content of germanium is preferably changed in the layer thickness direction of the i-type layer. In particular, it is a preferable distribution form of germanium that the germanium content continuously decreases in the direction of the n-type layer and / or the p-type layer. The distribution state of the germanium atoms in the layer thickness can be controlled by changing the flow rate ratio of the germanium-containing gas contained in the source gas.

As a method of changing the content of germanium atoms in the i-type layer by the MW plasma CVD method,
Other than the method of changing the flow rate ratio of the germanium-containing gas, the same can be done by changing the flow rate of hydrogen gas which is a dilution gas of the raw material gas. By increasing the amount of hydrogen dilution, the germanium content in the deposited film (i-type layer) can be increased.

The hydrogen plasma treatment of the present invention particularly improves the electrical connection between the so-called graded band gap layer in which germanium atoms are continuously changed as described above and the buffer layer in contact with the layer. is there.

More specifically, for example, as a pin junction i-type semiconductor layer suitable for the photovoltaic element of the present invention, i-type hydrogenated amorphous silicon (a-Si: H) is cited. The characteristic is that the optical bandgap (E
_g ) is 1.60 eV to 1.85 eV, hydrogen atom content (C _H ) is 1.0 to 25.0%, AM 1.5, 100 m
The photoelectric conductivity (σ _p ) under simulated sunlight irradiation of W / cm ² is 1.
0 × 10 ⁻⁵ S / cm or more, dark conductivity (σ _d ) 1.0 ×
10 ^-9 S / cm or less, the tilt of the backback tail by the constant photocurrent method (CPM) is 55 m
It is preferably eV or less and the localized level density is 10 ¹⁷ / cm ³ or less.

The amorphous silicon germanium semiconductor material, which constitutes the i-type semiconductor layer having a relatively narrow bandgap of the photovoltaic element of the present invention, has a characteristic that the optical bandgap (E _g ) is 1.20 eV. ~ 1.60 eV,
The hydrogen atom content (C _H ) is 1.0 to 25.0%, the slope of the arback tail by the constant photocurrent method (CPM) is 55 meV or less, and the localized level density is 10 ¹⁷ / cm ³ or less. The ones are the preferable ones.

The i-type layer suitable for the present invention is preferably deposited under the following conditions. The amorphous semiconductor layer is preferably deposited by RF, VHF or MW plasma CVD method.

When depositing by the RF plasma CVD method, the substrate temperature is 100 to 350 ° C., the vacuum degree in the deposition chamber is 0.05 to 10 Torr, and the RF frequency is 1 to 50 MHz. Especially the RF frequency is 1
3.56 MHz is suitable. The RF power supplied into the deposition chamber is preferably in the range of 0.01 to 5 W / cm ² . The self-bias applied to the substrate by the RF power is preferably 0 to 300V.

In the case of depositing by the VHF plasma CVD method, the substrate temperature is 100 to 450 ° C., the degree of vacuum in the deposition chamber is 0.0001 to 1 Torr, and the VHF frequency is 60.
To 99 MHz is a suitable range. The VHF power supplied to the deposition chamber is preferably in the range of 0.01 to 1 W / cm ² . Further, the self-bias applied to the substrate by the VHF power is preferably in the range of 10 to 1000V.

Further, the characteristics of the deposited amorphous film are improved by introducing a DC or RF into the deposition chamber by superposing it on VHF or by separately providing a bias rod. When introducing a DC bias using a bias rod,
It is preferred that the bias rod be positive. When the DC bias is introduced to the substrate side, it is preferable to introduce the DC bias so that the substrate side becomes the negative electrode. When introducing RF bias, RF is more than substrate area
It is preferable to reduce the area of the electrode into which is introduced.

When depositing by the MW plasma CVD method, the substrate temperature is 100 to 450 ° C., the degree of vacuum in the deposition chamber is 0.0001 to 0.05 Torr, and the MW frequency is 100 MHz to 10 GHz. In particular, the MW frequency is suitably 2.45 GHz. The MW power input into the deposition chamber is 0.01 to 1 W / cm ²
Is a preferable range. MW power is optimally introduced into the deposition chamber via a waveguide.

Further, in addition to the MW, a bias rod is separately provided and DC or RF is introduced into the deposition chamber to improve the characteristics of the deposited amorphous film. If the DC bias is introduced using a bias rod, it is preferred that the bias rod be positive. Also DC
When the bias is introduced to the substrate side, it is preferable to introduce it so that the substrate side becomes the negative electrode. When introducing the RF bias, it is preferable to make the area of the electrode for introducing the RF smaller than the area of the substrate.

Silane-based source gases such as SiH ₄ , Si ₂ H ₆ , SiF ₄ and SiF ₂ H ₂ are suitable for depositing the i-type layer suitable for the plasma treatment of the present invention. Further, in order to widen the band gap, it is preferable to add a gas containing carbon, nitrogen or oxygen. It is preferable that the gas containing carbon, nitrogen or oxygen is contained in a large amount in the vicinity of the p-type layer and / or the n-type layer, rather than being uniformly contained in the i-type layer. By doing so, the open circuit voltage can be improved without alienating the charge running property in the i-type layer.

As the carbon-containing gas, C _n H _{2n + 2} (n is an integer), C _n H _2n (n is an integer), C ₂ H _{2 and the} like are suitable. As the nitrogen-containing gas, N ₂ , NO, N ₂ O, N
O ₂ , NH _3, etc. are suitable. Oxygen-containing gas is O
₂ , CO ₂ , O _3, etc. are suitable. Also, a combination of a plurality of these gases may be introduced. As the amount of the source gas added to increase the band gap,
A suitable amount is 0.1 to 50%.

Further, an element of Group III or / and Group V of the periodic table is added to the i-type layer to improve the characteristics. Group III elements of the periodic table include B, Al, G
a and the like are suitable. Particularly when boron is added, it is preferable to add it by using a gas such as B ₂ H ₆ or BF ₃ . Further, as the group V element of the periodic table, N,
P, As, etc. are suitable. Especially when phosphorus is added, PH ₃ is mentioned as a suitable one. The suitable amount of the group III element and / or the group V element of the periodic table added to the i-type layer is 0.1 to 1000 ppm.

For the i-type layer, n / i buffer layer and p
By providing the / i buffer layer, the characteristics of the photovoltaic element are improved. As the buffer layer,
A semiconductor layer similar to the i-type layer can be used, in particular i
It is preferable to deposit at a slower deposition rate than the mold layer. As the buffer layer, a semiconductor having a wider band gap than the i-type layer is suitable. The band gap is
It is preferable that it is smoothly continuous from the i-type layer to the buffer layer. As a method for continuously changing the bandgap in the buffer layer, the bandgap can be narrowed by increasing the content of germanium atoms contained in the silicon-based non-single-crystal semiconductor. On the other hand, the band gap can be continuously widened by increasing the content of carbon atoms, oxygen atoms and / or nitrogen atoms contained in the silicon-based non-single-crystal semiconductor. The ratio of the narrowest and widest band gap is 1.01 to 1.5
Is a preferred range.

When an element of Group III or / and Group V of the periodic table is added to the buffer layer, n / i
To the buffer layer, a group III element of the periodic table is added, and p
It is preferable to add a group V element of the periodic table to the / i buffer layer. By doing so, it is possible to prevent deterioration of characteristics due to diffusion of impurities from the n-type layer and / or the p-type layer into the i-type layer.

(P-Type Layer, n-Type Layer) The p-type layer or the n-type layer in the present invention is an important layer that influences the characteristics of the photovoltaic device of the present invention, like the above-mentioned i-type layer. .

As an amorphous material (denoted as a-) (microcrystalline material (denoted as μc-)) of the p-type layer or n-type layer, it goes without saying that it falls into the category of amorphous materials. Is, for example, a-Si: H, a-Si: HX, a-Si
C: H, a-SiC: HX, a-SiGe: H, a-S
iGeC: H, a-SiO: H, a-SiN: H, a-
SiON: HX, a-SiOCN: HX, μc-Si:
H, μc-SiC: H, μc-Si: HX, μc-Si
C: HX, μc-SiGe: H, μc-SiO: H, μ
c-SiGeC: H, μc-SiN: H, μc-SiO
N: HX, μc-SiOCN: HX, etc. and a p-type valence electron control agent (Group III atom B, Al, Ga, I of the periodic table)
(n, Tl) or an n-type valence electron control agent (group V atom P, As, Sb, Bi of the periodic table) is added at a high concentration.

Polycrystalline material of p-type layer or n-type layer (poly)
Is displayed), for example, poly-Si:
H, poly-Si: HX, poly-SiC: H, p
poly-SiC: HX, poly-SiGe: H, po
poly-SiC, poly-SiC, poly-SiGe,
And a p-type valence electron control agent (group III atom B of the periodic table,
Examples thereof include Al, Ga, In, Tl) and n-type valence electron control agents (group V atoms P, As, Sb, Bi in the periodic table) added in high concentration.

Particularly, in the p-type layer or the n-type layer on the light incident side,
A crystalline semiconductor layer with little light absorption or an amorphous semiconductor layer with a wide band gap is suitable. The optimum amount of addition of the group III atom of the periodic table to the p-type layer and the addition amount of group V atom of the periodic table to the n-type layer are 0.1 to 50 at%.

Further, the hydrogen atom (H, D) or halogen atom contained in the p-type layer or the n-type layer has a function of compensating for dangling bonds of the p-type layer or the n-type layer. It improves the doping efficiency of the n-type layer. p-type layer or n
Hydrogen atom or halogen atom added to the mold layer is 0.1 to
An optimum amount is 40 at%. Especially when the p-type layer or the n-type layer is crystalline, the optimum amount of hydrogen atoms or halogen atoms is 0.1 to 8 at%.

Further, a preferable distribution mode is one in which the content of hydrogen atoms and / or halogen atoms is distributed in a large amount on each interface side of the p-type layer / i-type layer and the n-type layer / i-type layer. . At this time, the content of hydrogen atoms and / or halogen atoms near the interface is preferably in the range of 1.1 to 2 times the content in the bulk.
Thus, by increasing the content of hydrogen atoms or halogen atoms in the vicinity of each interface of the p-type layer / i-type layer and the n-type layer / i-type layer, the defect level and mechanical strain near the interface are reduced. It is possible to increase the photovoltaic power and the photocurrent of the photovoltaic device of the present invention.

Regarding the electrical characteristics of the p-type layer and the n-type layer of the photovoltaic element, the activation energy is preferably 0.2 eV or less, and most preferably 0.1 eV or less. The non-resistance is preferably 100 Ωcm or less, and most preferably 1 Ωcm or less. Furthermore, the layer thickness of the p-type layer and the n-type layer is 1 to
50 nm is preferable and 3 to 10 nm is optimum.

As the semiconductor layer of the photovoltaic element of the present invention,
In order to form a suitable group IV and group IV alloy-based amorphous semiconductor layer, the most preferable manufacturing method is the microwave plasma CVD method, and the next preferable manufacturing method is the RF plasma CVD method.

In the microwave plasma CVD method, a material gas such as a source gas and a diluent gas is introduced into the deposition chamber,
While evacuating with a vacuum pump, the internal pressure of the deposition chamber was kept constant, and microwaves oscillated by a microwave power source were guided by a waveguide and introduced into the deposition chamber through a dielectric window (alumina ceramics etc.). Is a method of generating plasma of material gas and decomposing it to form a desired deposited film on the substrate placed in the deposition chamber. The deposited film applicable to the photovoltaic device is formed under wide deposition conditions. can do.

As a source gas suitable for depositing the group IV and group IV alloy-based amorphous semiconductor layers suitable for the photovoltaic device of the present invention, a gasifiable compound containing a silicon atom, germanium atom, is used. A gasifiable compound containing,
Examples thereof include a gasizable compound containing a carbon atom, a gasizable compound containing a nitrogen atom, a gasizable compound containing an oxygen atom, and a mixed gas of the compound.

A chain or cyclic silane compound is specifically used as the gasifiable compound containing a silicon atom. Specific examples include SiH ₄ , Si ₂ H ₆ and Si.
F ₄ , SiFH ₃ , SiF ₂ H ₂ , SiF ₃ H, Si ₃ H ₈ ,
SiD ₄ , SiHD ₃ , SiH ₂ D ₂ , SiH ₃ D, SiF
D ₃ , SiF ₂ D ₂ , SiF ₃ D, Si ₂ D ₃ H ₃ , (Si
F ₂ ) ₅ , (SiF ₂ ) ₆ , (SiF ₂ ) ₄ , Si ₂ F ₆ , Si
_{3 F 8, Si 2 H 2} F 4, Si 2 H 3 F 3, SiCl 4, (Si
Cl ₂ ) ₅ , SiBr ₄ , (SiBr ₂ ) ₅ , Si ₂ Cl ₆ ,
SiHCl ₃ , SiH ₂ Br ₂ , SiH ₂ Cl ₂ , Si ₂ Cl
₃ which may or easily gasified gas conditions such as F ₃ and the like.

A gas containing specifically germanium atoms
GeH is a compound that can be converted into_Four, GeD_Four, GeF_Four,
GeFH_Three, GeF₂H₂, GeF_ThreeH, GeHD_Three, Ge
H₂D ₂, GeH_ThreeD, GeH₆, Ge₂D₆Etc.
You.

Specific examples of the gasifiable compound containing a carbon atom include CH ₄ , CD ₄ , C _n H _{2n + 2} (n is an integer), C _n H _2n (n is an integer), C ₂ H ₂ , C ₆ H ₆ , CO ₂ ,
CO etc. are mentioned.

As the nitrogen-containing gas, N ₂ , NH ₃ , N
D _3, NO, include NO _2, N ₂ O. Oxygen-containing gas includes O ₂ , CO, CO ₂ , NO, NO ₂ , N ₂ O, CH
₃ CH ₂ OH, CH ₃ OH and the like can be mentioned.

Further, as the substance introduced into the p-type layer or the n-type layer for controlling the valence electrons, there are group III atoms and group V atoms of the periodic table.

As the starting material effectively used for introducing a group III atom, specifically, for introducing a boron atom, B ₂ H ₆ , B ₄ H ₁₀ , B ₅ H ₉ and B _{5 can be used.} H ₁₁ , B
_{6 H 1 0, B 6 H} 12, B 6 H 14 , etc. borohydride, BF _3, B
Examples thereof include boron halides such as Cl ₃ .
In addition, AlCl ₃ , GaCl ₃ , InCl ₃ , TlC
Examples include l _{3 and the} like. B ₂ H ₆ and BF ₃ are particularly suitable.

What is effectively used as a starting material for introducing a Group V atom is specifically P for introducing a phosphorus atom.
Phosphorus hydride such as H ₃ and P ₂ H ₄ , PH ₄ I, PF ₃ , and PF ₅ ,
Examples thereof include phosphorus halides such as PCl ₃ , PCl ₅ , PBr ₃ , PBr ₅ , and PI ₃ . In addition, AsH ₃ , AsF ₃ ,
_{AsCl 3, AsBr 3, AsF 5} , SbH 3, SbF 3,
SbF ₅ , SbCl ₃ , SbCl ₅ , BiH ₃ , BiC
Other examples include l ₃ and BiBr ₃ . Especially PH ₃ ,
PF ₃ is suitable.

In addition, the gasifiable compound is replaced by H ₂ , H
It may be appropriately diluted with a gas such as e, Ne, Ar, Xe, or Kr and introduced into the deposition chamber.

In particular, when depositing a layer having small light absorption or a wide band gap such as a microcrystalline semiconductor or a-SiC: H, the source gas is diluted with hydrogen gas to 2 to 100 times, and microwave power or RF is applied. It is preferable to introduce a relatively high power.

(Transparent Electrode) The transparent electrode in the present invention is
In order to efficiently absorb the light from the sun, white fluorescent lamps, etc. in each semiconductor layer, it is desirable that the light transmittance is 85% or more. Furthermore, electrically, the resistance of the output of the photovoltaic element is high. Sheet resistance is 100 so that it does not become a component
Ω or less is desirable. Examples of materials having such special characteristics include SnO ₂ , In ₂ O ₃ , ZnO, CdO, and C.
Examples thereof include metal oxides such as d ₂ SnO ₄ and ITO (In ₂ O ₃ + SnO ₂ ), and metal thin films formed by forming a metal such as Au, Al and Cu in an extremely thin and semitransparent state.

In the photovoltaic element, the transparent electrode is laminated on the p-type layer or the n-type layer half, and the photovoltaic element is formed on the translucent support, and light is irradiated from the translucent support side. In the case of, it is necessary to select those having good mutual adhesion because they are laminated on the support. Further, it is preferable that the transparent electrode is deposited in a layer thickness suitable for the antireflection condition. As a method for manufacturing the transparent electrode, 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.

(Collecting Electrode) As the collecting electrode of the photovoltaic element subjected to the hydrogen plasma treatment in the present invention, for example, a silver paste formed by a screen printing method, C
A material in which r, Ag, Au, Cu, Ni, Mo, Al or the like is formed by a vacuum vapor deposition method using a mask is preferably used. Alternatively, a metal wire of Cu, Au, Ag, Al or the like may be attached with carbon or Ag powder together with a resin and attached to the surface of the photovoltaic element to form a collector electrode.

When manufacturing a photovoltaic device having a desired output voltage and output current using the photovoltaic element of the present invention, the photovoltaic elements of the present invention are connected in series or in parallel, A protective layer is formed on the front and back surfaces, and output extraction electrodes and the like are attached. When the photovoltaic elements of the present invention are connected in series, a diode for preventing backflow may be incorporated.

[0110]

EXAMPLES Hereinafter, the photovoltaic element of the present invention will be described in detail by the method for forming a substrate for a photovoltaic element of the present invention and the production of a photovoltaic element made of a non-single crystal silicon semiconductor material. The present invention is not limited to this.

Example 1 In this example, the photovoltaic device substrate 190 shown in FIG. 1 was produced using the multi-chamber separation type forming apparatus shown in FIG. That is, the layers 199, 101 and 102 were formed on the support 100. The manufacturing method will be described below according to the procedure. However, the forming apparatus of FIG. 3 includes a source gas supply device (not shown).
Are connected through a gas introduction pipe. The raw material gas cylinders are all refined to ultra-high purity. As the source gas cylinder, H ₂ gas cylinder, Ar gas cylinder,
A He gas cylinder was connected. As the target, Zn
O and Ag were arranged so that sputtering can be performed in vacuum.

As the support, a thickness of 0.5 mm, 50 ×
Using a 50 mm ² stainless steel plate, ultrasonic cleaning was performed with acetone and isopropanol, and dried with warm air. A DC power source 325 was connected as a sputtering power source, and a ZnO intermediate layer 199 was formed using a DC magnetron sputtering method.

The manufacturing method will be described below according to the procedure. (1) The washed support 390 (100 in FIG. 1) is arranged on the support transfer rail 313 in the load chamber 301, and the pressure inside the load chamber 301 is about 1 × 10 ⁻ by a vacuum exhaust pump (not shown). ^It was evacuated to ⁵ Torr.

(2) The gate valve 306 was opened to carry into the transfer chamber 302 and the deposition chamber 320, which had been evacuated by a vacuum exhaust pump (not shown) in advance. The back surface of the support 390 is provided with a heater 3 for heating the support.
The temperature of the support is set to 130 ° C. and the pressure in the deposition chamber 320 is adjusted to about 3 × 10 ⁻⁶ Torr by a vacuum exhaust pump (not shown).
It was evacuated until.

(3) Ar gas is supplied from the gas introduction pipe 324 to 3
Introducing 5 sccm, adjusting the pressure to 5 mTorr by a conductance valve (not shown), applying a current to the toroidal coil 323, and sputtering power sources 325 to 380.
V DC power was applied to generate Ar plasma. (4) When the target shutter 326 is opened and the intermediate layer 199 of ZnO having a layer thickness of 0.01 μm is formed on the surface of the stainless steel plate, the target shutter 326 is closed.
Extinguished the plasma.

(5) After raising the heater 310 for heating the support and lowering the temperature of the support to 100 ° C. or less at a temperature lowering speed of 4 ° C./S in a He gas atmosphere as a gas for cooling the support, a vacuum (not shown) is prepared in advance. The transfer chamber 303 and the deposition chamber 3 that have been evacuated by an exhaust pump.
The gate valve 307 was opened into the container 30 and conveyed. The back surface of the support 390 is brought into close contact with the support heating heater 311 and heated at a temperature rising speed of 16 ° C./S to adjust the support temperature to 29
The temperature was raised to 0 ° C. and the inside of the deposition chamber 330 was evacuated by a vacuum exhaust pump (not shown) until the pressure became about 2 × 10 ⁻⁶ Torr.

(6) Ar gas is supplied from the gas introduction pipe 334 to 5
0 sccm is introduced, the pressure is adjusted to 5 mTorr by a conductance valve (not shown), a current is applied to the toroidal coil 333, and sputtering power sources 335 to 380 are used.
V DC power was applied to generate Ar plasma. Next, the target shutter 336 is opened, and the Ag light reflection layer 10 having a layer thickness of 0.5 μm is formed on the surface of the intermediate layer 199 of ZnO.
When 1 was formed, the target shutter 336 was closed to extinguish the plasma.

(7) The heater 311 for heating the support is raised, and the temperature of the support is lowered to 100 ° C. or less at a temperature lowering speed of 5 ° C./S in a He gas atmosphere as a cooling gas for the support, and then again not shown in advance. The gate valve 307 was opened and the film was transferred into the transfer chamber 302 and the deposition chamber 320, which had been evacuated by the vacuum exhaust pump.
The back surface of the support 390 is brought into close contact with the support heating heater 310 and heated at a temperature rising rate of 15 ° C./S to raise the support temperature to 290 ° C., and the pressure inside the deposition chamber 320 is reduced to about 3 by a vacuum exhaust pump (not shown). The chamber was evacuated to × 10 ^-6 Torr.

(8) Ar gas 4
0 sccm is introduced, the pressure is adjusted to 4 mTorr by a conductance valve (not shown), a current is applied to the toroidal coil 323, and the sputtering power sources 325 to 385 are supplied.
V DC power was applied to generate Ar plasma. Next, the target shutter 326 is opened to open the Ag light reflection layer 1
01 ZnO reflection increasing layer 10 having a thickness of 1.2 μm on the surface
When 2 was formed, the target shutter 326 was closed to extinguish the plasma.

(9) Raise the heater 310 for heating the support, lower the temperature of the support to 100 ° C. or less at a temperature lowering speed of 6 ° C./S in a He gas atmosphere as a gas for cooling the support, and then perform vacuum evacuation (not shown) in advance. The gate valves 307 and 308 were opened and conveyed into the unload chamber 304 that had been evacuated by a pump. The fabrication of the photovoltaic device substrate of this example was completed as described above. This photovoltaic element substrate is called (S Ex 1).

Comparative Example 1-1 This example differs from Example 1 only in that the temperature of the support was set to 10 ° C. when the intermediate layer 199 of ZnO was formed. Other points were the same as in Example 1. The photovoltaic element substrate of this example is called (S ratio 1-1).

Comparative Example 1-2 This example differs from Example 1 only in that the temperature of the support was set to 60 ° C. when the intermediate layer 199 of ZnO was formed. Other points were the same as in Example 1. The photovoltaic element substrate of this example is called (S ratio 1-2).

Comparative Example 1-3 This example is different from Example 1 only in that the support temperature was 150 ° C. when the Ag light reflecting layer 101 was formed. Other points were the same as in Example 1. The photovoltaic element substrate of this example is called (S ratio 1-3).

Comparative Example 1-4 This example is different from Example 1 in that the support temperature was set to 550 ° C. when the Ag light reflecting layer 101 was formed. Other points were the same as in Example 1. The photovoltaic element substrate of this example is called (S ratio 1-4).

COMPARATIVE EXAMPLE 1-5 In this example, only the point where the ZnO reflection increasing layer 102 was formed without lowering the support temperature to 100 ° C. or lower after forming the Ag light reflecting layer 101 was the same as Example 1. different. Other points were the same as in Example 1.
The photovoltaic element substrate of this example is called (S ratio 1-5).

Comparative Example 1-6 This example differs from Example 1 only in that the support temperature was 150 ° C. when the ZnO reflection increasing layer 102 was formed. Other points were the same as in Example 1. The substrate for photovoltaic elements of this example is (S ratio 1-
I decided to call it 6).

Comparative Example 1-7 This example differs from Example 1 only in that the support temperature was set to 450 ° C. when forming the ZnO reflection increasing layer 102. Other points were the same as in Example 1. The substrate for photovoltaic elements of this example is (S ratio 1-
I decided to call it 7).

The above-mentioned eight types of substrates for photovoltaic elements, that is, (S Ex 1) and (S Ratio 1-1) to (S Ratio 1-7).
5 were produced for each. Table 1 shows the results of a bending peel test for examining the environment resistance characteristics of each of these photovoltaic element substrates. In addition, the results of evaluation of total reflectance and diffuse reflectance from the measurement of light reflectance are also shown.

In the bending and peeling test, each photovoltaic element substrate was subjected to a high temperature and high humidity atmosphere (temperature 80 ° C., humidity 80%).
After leaving it for 100 hours under the environment of 20
Repeat 10 times, further drop a weight of 10 kg from the height of 50 cm 10 times on the bent portion, and observe the peeling condition on the substrate with a Hitachi SEM (model number: S-4500, magnification: 50,000 times). It was The light reflectance is measured by a spectrometer (Hitachi: Spectrophotometer).
U-4000) was used to evaluate the total reflectance and diffuse reflectance at a wavelength of 800 nm.

In the results of the bending peeling test shown in Table 1, the mark ◯ indicates the case where there was no peeling at all, and the mark Δ indicates the case where there was a slight peeling. The results of the total reflectance and diffuse reflectance are the results before the test and the results after the test are standardized for each photovoltaic element substrate.

[0131]

[Table 1] From the results of Table 1, the photovoltaic element substrate of Example 1 (S Ex 1) is the photovoltaic element substrate of seven comparative examples (S ratio 1-
It was found that all evaluation results were simultaneously superior to 1) to (S ratio 1-7).

Example 2 This example is different from Example 1 in that a substrate for a photovoltaic element was produced by using H ₂ gas as a support cooling gas instead of He gas.

As in Example 1, the multi-chamber separation type forming apparatus shown in FIG. 3 was used to produce the substrate 190 for photovoltaic element shown in FIG. That is, the layers 199, 101 and 102 were formed on the support 100. The manufacturing method will be described below according to the procedure. However,
A raw material gas supply device (not shown) is connected to the forming device of FIG. 3 through a gas introduction pipe. The raw material gas cylinder is
All of them were purified to ultra-high purity. As the source gas cylinder, H ₂ gas cylinder, Ar gas cylinder, He
The gas cylinder was connected. As a target, ZnO,
It was arranged so that it could be sputtered in vacuum using Ag.

The support has a thickness of 0.5 mm and 50 ×
Using a 50 mm ² stainless steel plate, ultrasonic cleaning was performed with acetone and isopropanol, and dried with warm air. A DC power source 325 was connected as a sputtering power source, and a ZnO intermediate layer 199 was formed using a DC magnetron sputtering method.

The manufacturing method will be described below in accordance with the procedure. (1) The washed support 390 (100 in FIG. 1) is arranged on the support transfer rail 313 in the load chamber 301, and the pressure inside the load chamber 301 is about 1 × 10 ⁻ by a vacuum exhaust pump (not shown). ^It was evacuated to ⁵ Torr.

(2) The gate valve 306 was opened to carry into the transfer chamber 302 and the deposition chamber 320, which had been evacuated by a vacuum exhaust pump (not shown) in advance. The back surface of the support 390 is provided with a heater 3 for heating the support.
The temperature of the support is set to 250 ° C., and the pressure inside the deposition chamber 320 is adjusted to about 3 × 10 ⁻⁶ Torr by a vacuum exhaust pump (not shown).
It was evacuated until.

(3) Ar gas is supplied from the gas introduction pipe 324 to 4
0 sccm is introduced, the pressure is adjusted to 4 mTorr by a conductance valve (not shown), a current is applied to the toroidal coil 323, and sputtering power supplies 325 to 375 are used.
V DC power was applied to generate Ar plasma. (4) The target shutter 326 is opened, and a ZnO intermediate layer 199 having a layer thickness of 0.015 μm is formed on the surface of the stainless steel plate.
When the target was formed, the target shutter 326 was closed to extinguish the plasma.

(5) After raising the heater 310 for heating the support and lowering the temperature of the support to 100 ° C. or less at a temperature lowering speed of 6 ° C./S in an atmosphere of H ₂ gas for cooling the support, it is not shown in advance. The transfer chamber 303 and the deposition chamber 3 that have been evacuated by a vacuum exhaust pump.
The gate valve 307 was opened into the container 30 and conveyed. The back surface of the support 390 is brought into close contact with the heater 311 for heating the support and heated at a temperature rising speed of 15 ° C./S.
The temperature was raised to 0 ° C. and the inside of the deposition chamber 330 was evacuated by a vacuum exhaust pump (not shown) until the pressure became about 2 × 10 ⁻⁶ Torr.

(6) Ar gas of 3 is supplied from the gas introduction pipe 334.
5 sccm is introduced, the pressure is adjusted to 4 mTorr by a conductance valve (not shown), a current is supplied to the toroidal coil 333, and a sputtering power supply 335 to 380 is supplied.
V DC power was applied to generate Ar plasma. Next, the target shutter 336 is opened, and the Ag light reflection layer 10 having a layer thickness of 0.6 μm is formed on the surface of the ZnO intermediate layer 199.
When 1 was formed, the target shutter 336 was closed to extinguish the plasma.

(7) Raise the heater 311 for heating the support, lower the temperature of the support to 100 ° C. or less at a temperature lowering speed of 8 ° C./S in an atmosphere of H ₂ gas for cooling the support, and then restart the operation in advance. The gate valve 307 was opened to carry into the transfer chamber 302 and the deposition chamber 320, which had been evacuated by the illustrated vacuum exhaust pump.
The back surface of the support 390 is brought into close contact with the heater 310 for heating the support and heated at a temperature rising rate of 12 ° C./S to raise the temperature of the support to 310 ° C. and the pressure inside the deposition chamber 340 to about 3 by a vacuum exhaust pump (not shown). The chamber was evacuated to × 10 ^-6 Torr.

(8) Ar gas of 5 is supplied from the gas introduction pipe 324.
Introducing 5 sccm, adjusting the pressure to 4 mTorr with a conductance valve (not shown), applying a current to the spherical coil 323, sputtering power sources 325 to 385
V DC power was applied to generate Ar plasma. Next, the target shutter 326 is opened to open the Ag light reflection layer 1
01 ZnO reflection enhancement layer 10 with a thickness of 1.5 μm on the surface
When 2 was formed, the target shutter 326 was closed to extinguish the plasma.

(9) Raise the heater 310 for heating the support, lower the temperature of the support to 100 ° C. or less at a temperature lowering speed of 15 ° C./S in an atmosphere of H ₂ gas for cooling the support, and then use a vacuum not shown in advance. The gate valves 307 and 308 were opened and transferred into the transfer chamber 303 and the unload chamber 304 that had been evacuated by the exhaust pump. The fabrication of the photovoltaic device substrate of this example was completed as described above. This photovoltaic element is called (S Ex 2).

(Comparative Example 2-1) After the Ag light-reflecting layer 101 was formed, the support temperature was not cooled to 100 ° C. or lower and Zn was used.
The difference from Example 2 is that the O reflection increasing layer 102 is formed. The other points were the same as in Example 2. The photovoltaic element substrate of this example is called (S ratio 2-1).

Five of each of the above-mentioned two types of substrates for photovoltaic elements, that is, (S Ex 2) and (S ratio 2-1) were prepared. Table 2 shows the results of a bending peel test for examining the environmental resistance of each of these photovoltaic element substrates. In addition, the results of evaluation of total reflectance and diffuse reflectance from the measurement of light reflectance are also shown. The evaluation method regarding the bending peeling test and the measurement of the light reflectance was performed in the same manner as in Example 1.

In the results of the bending peeling test shown in Table 2, the mark ◯ indicates that there was no peeling at all, and the mark X indicates that there was partial peeling. The results of the total reflectance and diffuse reflectance are the results before the test and the results after the test are standardized for each photovoltaic element substrate.

[0146]

[Table 2] From the results of Table 2, the photovoltaic device substrate of Example 2 (S Ex 2) is superior to the photovoltaic device substrate of Comparative Example (S ratio 2-1) in all evaluation results at the same time. I found out that Further, it was found that H ₂ gas was effective as the support cooling gas.

Example 3 This example is different from Example 1 in that a substrate for a photovoltaic element was prepared by using Ar gas as a support cooling gas instead of He gas.

As in Example 1, the multi-chamber separation type forming apparatus shown in FIG. 3 was used to produce the photovoltaic element substrate 190 shown in FIG. That is, the layers 199, 101 and 102 were formed on the support 100. The manufacturing method will be described below according to the procedure. However,
A raw material gas supply device (not shown) is connected to the forming device of FIG. 3 through a gas introduction pipe. The raw material gas cylinder is
All of them were purified to ultra-high purity. As the source gas cylinder, H ₂ gas cylinder, Ar gas cylinder, He
The gas cylinder was connected. As a target, ZnO,
It was arranged so that it could be sputtered in vacuum using Ag.

The support has a thickness of 0.5 mm and 50 ×
Using a 50 mm ² stainless steel plate, ultrasonic cleaning was performed with acetone and isopropanol, and dried with warm air. A DC power source 325 was connected as a sputtering power source, and a ZnO intermediate layer 199 was formed using a DC magnetron sputtering method.

The manufacturing method will be described below in accordance with the procedure. (1) The washed support 390 (100 in FIG. 1) is arranged on the support transfer rail 313 in the load chamber 301, and the pressure inside the load chamber 301 is about 1 × 10 ⁻ by a vacuum exhaust pump (not shown). ^It was evacuated to ⁵ Torr.

(2) The gate valve 306 was opened to carry into the transfer chamber 302 and the deposition chamber 320, which had been evacuated by a vacuum exhaust pump (not shown) in advance. The back surface of the support 390 is provided with a heater 3 for heating the support.
It is brought into close contact with No. 10 and heated at a heating rate of 10 ° C./S, the temperature of the support is set to 220 ° C., and the pressure inside the deposition chamber 320 is set to about 3 × 10 ⁻⁶ Torr by a vacuum exhaust pump (not shown).
It was evacuated until.

(3) Ar gas is supplied from the gas introduction pipe 324 to 3
Introducing 5 sccm, adjusting the pressure to 4 mTorr with a conductance valve (not shown), applying a current to the toroidal coil 323, and sputtering power sources 325 to 370.
V DC power was applied to generate Ar plasma. (4) The target shutter 326 is opened, and an intermediate layer 199 of ZnO having a layer thickness of 0.008 μm is formed on the surface of the stainless steel plate.
When the target was formed, the target shutter 326 was closed to extinguish the plasma.

(5) After raising the heater 310 for heating the support and lowering the temperature of the support to 100 ° C. or less at a temperature lowering speed of 3 ° C./S in an Ar gas atmosphere as a gas for cooling the support, a vacuum not shown in advance is prepared. The transfer chamber 303 and the deposition chamber 3 that have been evacuated by an exhaust pump.
The gate valve 307 was opened into the container 30 and conveyed. The back surface of the support 390 is brought into close contact with the support heating heater 311 and heated at a temperature rising speed of 16 ° C./S to adjust the support temperature to 29
The temperature was raised to 0 ° C. and the inside of the deposition chamber 330 was evacuated by a vacuum exhaust pump (not shown) until the pressure became about 2 × 10 ⁻⁶ Torr.

(6) Ar gas of 4 is supplied from the gas introduction pipe 334.
5 sccm is introduced, the pressure is adjusted to 4 mTorr by a conductance valve (not shown), a current is supplied to the toroidal coil 333, and a sputtering power supply 335 to 380 is supplied.
V DC power was applied to generate Ar plasma. Next, the target shutter 336 is opened, and the Ag light reflection layer 10 having a layer thickness of 0.7 μm is formed on the surface of the intermediate layer 199 of ZnO.
When 1 was formed, the target shutter 336 was closed to extinguish the plasma.

(7) The heater 311 for heating the support is raised, and the temperature of the support is lowered to 100 ° C. or less at a cooling rate of 3 ° C./S in an Ar gas atmosphere as a gas for cooling the support, and then again not shown in advance. The gate valve 307 was opened and the film was transferred into the transfer chamber 302 and the deposition chamber 320, which had been evacuated by the vacuum exhaust pump.
The back surface of the support 390 is brought into close contact with the support heating heater 310 and heated at a temperature rising rate of 12 ° C./S, the support temperature is set to 310 ° C., and the pressure inside the deposition chamber 320 is reduced to about 3 by a vacuum exhaust pump (not shown). The chamber was evacuated to × 10 ^-6 Torr.

(8) Ar gas of 4 is supplied from the gas introduction pipe 324.
0 sccm is introduced, the pressure is adjusted to 5 mTorr by a conductance valve (not shown), a current is applied to the spherical coil 323, and the sputtering power sources 325 to 385 are supplied.
V DC power was applied to generate Ar plasma. Next, the target shutter 326 is opened to open the Ag light reflection layer 1
01 reflection-increasing layer 10 of ZnO having a thickness of 1.1 μm on the surface
When 2 was formed, the target shutter 326 was closed to extinguish the plasma.

(9) Raise the heater 310 for heating the support, lower the temperature of the support to 100 ° C. or less at a temperature lowering speed of 5 ° C./S in an Ar gas atmosphere as a gas for cooling the support, and then evacuate (not shown) in advance. The gate valves 307 and 308 were opened and transferred into the transfer chamber 303 and the unload chamber 304 that had been evacuated by a pump. The fabrication of the photovoltaic device substrate of this example was completed as described above. This photovoltaic element substrate is called (S Ex 3).

(Comparative Example 3-1) In this example, the ZnO intermediate layer 199 was not formed, the Ag light reflecting layer 101 was formed, and then the support temperature was not cooled to 100 ° C. or lower.
The third embodiment is different from the third embodiment in that the reflection increasing layer 102 is formed.
Other points were the same as in Example 3. The photovoltaic element substrate of this example is called (S ratio 3-1).

Five of each of the above-mentioned two types of substrates for photovoltaic elements, that is, (S Ex 3) and (S Ratio 3-1) were prepared. Table 3 shows the results of a bending peel test for examining the environmental resistance characteristics of each of these photovoltaic element substrates. In addition, the results of evaluation of total reflectance and diffuse reflectance from the measurement of light reflectance are also shown. The evaluation method regarding the bending peeling test and the measurement of the light reflectance was performed in the same manner as in Example 1.

In the results of the bending peeling test shown in Table 3, the mark ◯ indicates that there was no peeling at all, and the mark X indicates that there was partial peeling. The results of the total reflectance and diffuse reflectance are the results before the test and the results after the test are standardized for each photovoltaic element substrate.

[0161]

[Table 3] From the results of Table 3, the photovoltaic device substrate of Example 3 (S Ex 3) is superior to the photovoltaic device substrate of Comparative Example (S ratio 3-1) in all evaluation results at the same time. I found out that Further, it has been found that Ar gas is effective as the support cooling gas.

Example 4 In this example, a gas used for forming the reflection enhancing layer 102 made of ZnO was replaced with Ar gas, and Ar gas and O ₂ gas were simultaneously used to produce a photovoltaic device. The difference from Example 1 is that a substrate was manufactured.

As in Example 1, the multi-chamber separation type forming apparatus shown in FIG. 3 was used to produce the photovoltaic element substrate 190 shown in FIG. That is, the layers 199, 101 and 102 were formed on the support 100. The manufacturing method will be described below according to the procedure. However,
A raw material gas supply device (not shown) is connected to the forming device of FIG. 3 through a gas introduction pipe. The raw material gas cylinder is
All of them were purified to ultra-high purity. As the source gas cylinder, H ₂ gas cylinder, Ar gas cylinder, He
The gas cylinder was connected. As a target, ZnO,
It was arranged so that it could be sputtered in vacuum using Ag.

As the support, a thickness of 0.5 mm, 50 ×
Using a 50 mm ² stainless steel plate, ultrasonic cleaning was performed with acetone and isopropanol, and dried with warm air. A DC power source 325 was connected as a sputtering power source, and a ZnO intermediate layer 199 was formed using a DC magnetron sputtering method.

The manufacturing method will be described below in accordance with the procedure. (1) The washed support 390 (100 in FIG. 1) is arranged on the support transfer rail 313 in the load chamber 301, and the pressure inside the load chamber 301 is about 1 × 10 ⁻ by a vacuum exhaust pump (not shown). ^It was evacuated to ⁵ Torr.

(2) The gate valve 306 was opened to carry into the transfer chamber 302 and the deposition chamber 320, which had been evacuated by a vacuum exhaust pump (not shown) in advance. The back surface of the support 390 is provided with a heater 3 for heating the support.
10 is adhered to 10 and heated at a temperature rising rate of 13 ° C./S, the temperature of the support is set to 290 ° C., and the pressure inside the deposition chamber 320 is set to about 3 × 10 ⁻⁶ Torr by a vacuum exhaust pump (not shown).
It was evacuated until.

(3) Ar gas of 5 is supplied from the gas introduction pipe 324.
0 sccm is introduced, O ₂ gas is introduced at 50 sccm, the pressure is adjusted to 2 mTorr by a conductance valve (not shown), a current is applied to the toroidal coil 323, DC power of 370 V is applied from the sputtering power source 325, and Ar / O ₂ plasma was generated. (4) When the target shutter 326 is opened and the intermediate layer 199 of ZnO having a layer thickness of 0.01 μm is formed on the surface of the stainless steel plate, the target shutter 326 is closed.
Extinguished the plasma.

(5) After raising the heater 310 for heating the support and lowering the temperature of the support to 100 ° C. or less at a cooling rate of 6 ° C./S in a He gas atmosphere as a cooling gas for the support, a vacuum not shown in advance is prepared. The transfer chamber 303 and the deposition chamber 3 that have been evacuated by an exhaust pump.
The gate valve 307 was opened into the container 30 and conveyed. The back surface of the support 390 is brought into close contact with the heater 311 for heating the support and heated at a temperature rising speed of 15 ° C./S.
The temperature was raised to 0 ° C. and the inside of the deposition chamber 330 was evacuated by a vacuum exhaust pump (not shown) until the pressure became about 2 × 10 ⁻⁶ Torr.

(6) Ar gas of 5 is supplied from the gas introduction pipe 334.
5 sccm is introduced, the pressure is adjusted to 4 mTorr by a conductance valve (not shown), a current is supplied to the toroidal coil 333, and a sputtering power supply 335 to 380 is supplied.
V DC power was applied to generate Ar plasma. Next, the target shutter 336 is opened, and the Ag light reflection layer 10 having a layer thickness of 0.6 μm is formed on the surface of the ZnO intermediate layer 199.
When 1 was formed, the target shutter 336 was closed to extinguish the plasma.

(7) After raising the heater 311 for heating the support and lowering the temperature of the support to 100 ° C. or less at a temperature lowering speed of 5 ° C./S in a He gas atmosphere as a gas for cooling the support, again not shown in advance. The gate valve 307 was opened and the film was transferred into the transfer chamber 302 and the deposition chamber 320, which had been evacuated by the vacuum exhaust pump.
The back surface of the support 390 is brought into close contact with the heater 310 for heating the support and heated at a temperature rising rate of 18 ° C./S to raise the temperature of the support to 315 ° C., and the pressure inside the deposition chamber 320 is reduced to about 3 by a vacuum exhaust pump (not shown). The chamber was evacuated to × 10 ^-6 Torr.

(8) Ar gas of 4 is supplied from the gas introduction pipe 324.
0 sccm, 40 sccm of O ₂ gas was introduced, and the pressure was 2
Adjust to a mTorr with a conductance valve (not shown), apply a current to the toroidal coil 323, apply DC power of 380 V from the sputter power supply 325, and
/ O ₂ plasma was generated. Next, the target shutter 326 is opened to form a layer thickness of 1.
When the reflection-increasing layer 102 of ZnO having a thickness of 5 μm was formed, the target shutter 326 was closed to extinguish the plasma.

(9) Raise the heater 310 for heating the support, lower the temperature of the support to 100 ° C. or less at a temperature lowering speed of 20 ° C./S in a He gas atmosphere as a gas for cooling the support, and then evacuate (not shown) in advance. The gate valves 307 and 308 were opened and transferred into the transfer chamber 303 and the unload chamber 304 that had been evacuated by a pump. The fabrication of the photovoltaic device substrate of this example was completed as described above. This photovoltaic element substrate is called (S Ex 4).

(Comparative Example 4-1) In this example, after the ZnO intermediate layer 199 was not formed and the Ag light reflecting layer 101 was formed, the ZnO intermediate layer 199 was not cooled to 100 ° C. or lower.
The third embodiment is different from the third embodiment in that the reflection increasing layer 102 is formed.
Other points were the same as in Example 3. The photovoltaic element substrate of this example is called (S ratio 4-1).

The above-mentioned two types of substrates for photovoltaic elements, that is, (S Ex 4) and (S Ratio 4-1), were produced in groups of 4 each. Table 4 shows the results of a bending peel test for examining the environmental resistance characteristics of each of these photovoltaic element substrates. In addition, the results of evaluation of total reflectance and diffuse reflectance from the measurement of light reflectance are also shown. The evaluation method regarding the bending peeling test and the measurement of the light reflectance was performed in the same manner as in Example 1.

In the results of the bending and peeling test shown in Table 4, the mark ◯ indicates that there was no peeling, and the mark x indicates that there was partial peeling. The results of the total reflectance and diffuse reflectance are the results before the test and the results after the test are standardized for each photovoltaic element substrate.

[0176]

[Table 4] From the results in Table 4, the photovoltaic device substrate of Example 4 (S Ex 4) was simultaneously superior to the photovoltaic device substrate of Comparative Example (S ratio 4-1) in all evaluation results. I found out that

Example 5 In this example, a substrate for a photovoltaic element of the present invention formed by the same method as in Example 1 was used,
The photovoltaic device shown in FIG. 1 was produced using the multi-chamber separation type forming apparatus shown in FIG. Forming apparatus 400 of FIG.
Can perform both MWPCVD and RFPCVD methods. Using this, each semiconductor layer was formed on the reflection increasing layer 102.

The manufacturing method will be described below in accordance with the procedure. However, a source gas supply device (not shown) is connected to the forming device of FIG. 3 through a gas introduction pipe. The raw material gas cylinders are all refined to ultra-high purity. As a raw material gas cylinder, a SiH ₄ gas cylinder,
CH ₄ gas cylinder, GeH ₄ gas cylinder, Si ₂ H ₆ gas cylinder, PH ₃ / H ₂ (dilution degree: 0.1%) gas cylinder, B
₂ H ₆ / H ₂ (dilution: 0.2%) gas cylinder, H ₂ gas cylinder, He gas cylinder, SiCl ₂ H ₂ gas cylinder, Si
A H ₄ / H ₂ (dilution: 1%) gas cylinder was connected.

(1) Intermediate layer 199 and light reflecting layer 1 of the present invention
01, the substrate on which the reflection increasing layer 102 is formed is placed on the substrate transfer rail 413 in the load chamber 401, and the load chamber 4 is loaded by a vacuum exhaust pump (not shown).
The inside of the chamber No. 01 was evacuated until the pressure reached about 1 × 10 ⁻⁵ Torr.

(2) The gate valve 406 is opened to carry into the transfer chamber 402 and the deposition chamber 417 which have been evacuated by a vacuum exhaust pump (not shown) in advance. The back surface of the substrate was brought into close contact with the substrate heating heater 410 to heat it, and the inside of the deposition chamber 417 was evacuated by a vacuum exhaust pump (not shown) until the pressure became about 1 × 10 ⁻⁵ Torr.

(3) After the preparation for film formation is completed as described above, H ₂ gas is introduced into the deposition chamber 417 through the gas introduction pipe 429, and the H ₂ gas flow rate is 300 sccc.
Open the valves 441, 431, 430 so that
It was adjusted with the mass flow controller 436. The pressure inside the deposition chamber 417 was adjusted to 1.3 Torr by a conductance valve (not shown). The substrate heating heater 410 was set so that the substrate temperature was 350 ° C.

(4) When the substrate temperature is stable, μc
The RF n-type layer 103 made of —Si was formed. μc-S
To form an RF n-type layer made of i, SiH ₄ gas,
PH ₃ / H ₂ gas is introduced into the deposition chamber 417 by the valve 44.
Operate 3, 433, 444, 434 to operate the gas introduction pipe 42
Introduced through 9. At this time, the SiH ₄ gas flow rate is 2 s
The mass flow controllers 438, 436, and 439 were adjusted so that the ccm and H ₂ gas flow rates were 120 sccm and the PH ₃ / H ₂ gas flow rates were 200 sccm, and the pressure in the deposition chamber 417 was adjusted to 1.1 Torr.

The power of the RF power source 422 is 0.05 W / cm.
Set to ² , RF power is introduced into the plasma forming cup 420, glow discharge is generated, formation of the RFn type layer is started on the substrate, and the RF power source is turned off when the RFn type layer having a layer thickness of 18 nm is formed. Then, the glow discharge was stopped and the formation of the RF n-type layer 103 was completed. Stop the inflow of SiH ₄ gas, PH ₃ / H ₂ gas, and H ₂ gas into the deposition chamber 417,
The deposition chamber and the gas pipe were evacuated to 1 × 10 ⁻⁵ Torr.

(5) RFi type layer 15 made of a-Si
1. MWi type layer 104 made of a-SiGe, a-Si
RFi-type layer 161 made of a, RFp made of a-SiC
The mold layer 105 was sequentially formed. First, not shown in advance
Transfer chamber that has been evacuated by a vacuum pump
-403 and i-type layer deposition chamber 418
The tube 407 was opened to transfer the substrate. The back side of the board
The i-type layer deposition chip is heated by being brought into close contact with the heating heater 411.
The chamber 418 is pressurized by a vacuum exhaust pump (not shown).
Is about 1 × 10 ^-FiveIt was evacuated to Torr.

(6) To prepare the RFi type layer,
Heater 411 for heating the substrate so that the temperature becomes 290 ° C.
The valve 46 when the substrate is sufficiently heated.
Gradually open 4, 454, 450, 463, 453,
Si₂H₆Gas, H₂Gas through the gas introduction pipe 449 i
It was made to flow into the mold layer deposition chamber 418. At this time, S
i ₂H₆Gas flow rate is 4 sccm, H₂Gas flow rate is 120s
Each mass flow controller 4 to be ccm
Adjusted at 59, 458. i-type layer deposition chamber 418
The internal pressure should be 0.7 Torr, which is not shown.
Adjusted the opening of the dactance valve.

Next, the RF power source 424 is set to 0.008 W / c.
Setting to m ² , applying to the bias rod 428, causing glow discharge, opening the shutter 427 to start the production of the i-type layer on the RF n-type layer, and when the i-type layer having a layer thickness of 10 nm was produced. Stop RF glow discharge, RF power supply 42
The output of No. 4 was cut off, and the fabrication of the RFi type layer 151 was completed.

The valves 464, 454, 453 and 450 are closed to stop the inflow of Si ₂ H ₆ gas and H ₂ gas into the i-type layer deposition chamber 418 and the i-type layer deposition chamber 418.
The inside and the gas pipe were evacuated to 1 × 10 ⁻⁵ Torr.

(7) To prepare the MWi type layer, the substrate heating heater 411 is controlled so that the temperature of the substrate becomes 380 ° C.
After setting, when the substrate is sufficiently heated, the valve 461,
451, 450, 462, 452, 463, 453 were gradually opened, and SiH ₄ gas, GeH ₄ gas, and H ₂ gas were caused to flow into the i-type layer deposition chamber 418 through the gas introduction pipe 449.

At this time, the SiH ₄ gas flow rate was 45 scc.
m, GeH ₄ gas flow rate is 37 sccm, H ₂ gas flow rate is 1
The mass flow controllers 456, 457, and 458 were adjusted so as to be 50 sccm. The opening of the conductance valve (not shown) was adjusted so that the pressure in the i-type layer deposition chamber 418 became 5 mTorr. Next, the RF power source 424 was set to 0.30 W / cm ² and applied to the bias rod 428.

After that, a μW power source (2.45 GH, not shown)
z) power is set to 0.10 W / cm ² and the waveguide 42
6, and μW electric power is introduced into the i-type layer deposition chamber 418 through the microwave introduction window 425 to cause glow discharge, and the shutter 427 is opened to start production of the MWi-type layer on the RFi-type layer. When the i-type layer having a thickness of 0.17 μm was produced, μW glow discharge was stopped, the output of the bias power source 424 was cut off, and the production of the MWi-type layer 104 was completed. The valves 451, 452 and 453 are closed to stop the inflow of SiH ₄ gas, GeH ₄ gas and H ₂ gas into the i-type layer deposition chamber 418, and the i-type layer deposition chamber 41
The inside of 8 and the inside of the gas pipe were evacuated to 1 × 10 ⁻⁵ Torr.

(8) To prepare the RFi type layer,
Heater 411 for heating the substrate so that the temperature becomes 250 ° C.
The valve 46 when the substrate is sufficiently heated.
Gradually open 4, 454, 450, 463, 453,
Si₂H₆Gas, H₂Gas through the gas introduction pipe 449 i
It was made to flow into the mold layer deposition chamber 418. At this time, S
i ₂H₆Gas flow rate is 3 sccm, H₂Gas flow is 90sc
Each mass flow controller 45 to be cm
Adjusted at 9,458. In the i-type layer deposition chamber 418
Pressure is 0.7 Torr.
The opening of the cance valve was adjusted. Next, the RF power source 42
4 to 0.007 W / cm²Set to the bias bar 428
Applied to the shutter 427 to cause glow discharge,
Opening starts fabrication of RFi type layer on MWi type layer
Then, when the i-type layer with a layer thickness of 20 nm was produced, the RF
-Stop the discharge, turn off the output of the RF power supply 424, RFi type
The fabrication of the layer 161 is completed. Valves 464, 454, 45
3, 450 closed and into i-type layer deposition chamber 418
Si₂H₆Gas H₂Stop the inflow of gas, i-type layer deposition cha
1 × 10 inside the gas bar 418 and gas pipe^-FiveTorr
It was evacuated to.

(9) RF p-type layer 10 made of a-SiC
5 is formed, the transfer chambers 404 and p are evacuated by a vacuum exhaust pump (not shown) in advance.
The gate valve 408 was opened into the mold layer deposition chamber 419 to transfer the substrate. The back surface of the substrate is brought into close contact with the heater 412 for heating the substrate and heated, and the p-type layer deposition chamber 419
The inside pressure is about 1 × 10 ^-5 by a vacuum exhaust pump (not shown).
It was evacuated to Torr.

The substrate is heated so that the temperature of the substrate becomes 220.degree.
Set the heater for heat 412 and make sure that the substrate temperature is stable.
By the way, H₂Gas, SiH_Four/ H₂Gas, B₂H₆/ H₂gas,
CH _FourA gas is introduced into the deposition chamber 419 through a valve 481;
471, 470, 482, 472, 483, 473, 4
Operate 84, 474 and introduce through gas introduction pipe 469
did. At this time, H₂Gas flow rate is 60 sccm, SiH_Four/
H₂Gas flow rate is 2 sccm, B₂H₆/ H₂Gas flow rate is 10
sccm, CH_FourGas flow rate should be 0.3 sccm
Mass flow controllers 476, 477, 478,
The pressure in the deposition chamber 419 is 1.
Conductance valve not shown so as to be 8 Torr
Adjusted the opening. The power of the RF power source 423 is 0.07W
/ Cm²Set to RF on the plasma forming cup 421.
Introduce electric power to cause glow discharge and RF on the i-type layer
Start the formation of the p-type layer and form the RF p-type layer with a layer thickness of 10 nm.
Turn off the RF power to stop glow discharge,
The formation of the RF p-type layer 105 is completed.

Valves 472, 482, 473, 483,
474, 484, 471, 481, 470 are closed and SiH ₄ / H ₂ gas into the p-type layer deposition chamber 419, B ₂
The inflow of H ₆ / H ₂ gas, CH ₄ gas, and H ₂ gas was stopped, and the inside of the p-type layer deposition chamber 419 and the gas pipe was set to 1 × 10.
Evacuated to ^-5 Torr.

(10) Unload chamber 40 evacuated in advance by a vacuum exhaust pump (not shown)
5, the gate valve 409 is opened to transfer the substrate, a leak valve (not shown) is opened, and the unload chamber 405 is opened.
Leaked.

(11) As a transparent conductive layer 112, ITO having a layer thickness of 70 nm was vacuum-deposited on the RF p-type layer 105 by a vacuum vapor deposition method. (12) Place a mask having comb-shaped holes on the transparent conductive layer 112, and perform Cr (40 nm) / Ag (1000 nm) / C.
A comb-shaped collector electrode 113 made of r (40 nm) was vacuum-deposited by a vacuum deposition method. This completes the production of the photovoltaic device of this example. This photovoltaic element is called (SC Ex 5).

Comparative Example 5-1 In this example, the ZnO intermediate layer 199 was not formed, and after the Ag light reflecting layer 101 was formed, the support temperature was not cooled to 100 ° C. or lower.
The difference from Example 5 is that the reflection increasing layer 102 is formed.
The other points were the same as in Example 5. The photovoltaic element of this example is called (SC ratio 5-1).

The above-mentioned two types of photovoltaic elements, that is, (SC Ex 5) and (SC Ratio 5-1), were produced in 6 pieces each. Table 5 shows the results of a bending peel test for examining the environmental resistance characteristics of each of these photovoltaic elements. Also, the initial photoelectric conversion efficiency (photovoltaic power / incident light power)
The results of evaluation of various characteristics of are also shown.

In the bending peel test, each photovoltaic element substrate was subjected to a high temperature and high humidity atmosphere (temperature 80 ° C., humidity 80%).
Bending test for 30 hours
Repeat 10 times, drop a weight of 10 kg from the height of 50 cm on the bent portion 10 times, and observe the peeling condition on the substrate with Hitachi SEM (model number: S-4500, magnification: 50,000 times). It was In addition, the characteristics of the initial photoelectric conversion efficiency are as follows:
Installed under 1.5 (100 mW / cm ² ) light irradiation,
It was evaluated by measuring the -I characteristic.

In the results of the bending peeling test shown in Table 5, the mark ◯ indicates that there was no peeling, and the mark x indicates that there was partial peeling. In addition, the evaluation results regarding the various characteristics of the initial photoelectric conversion efficiency shown in Table 5, that is, the evaluation results of the photoelectric conversion efficiency, the short-circuit current, and the open circuit voltage are the results of the photovoltaic element (SC Ex 5), and Electromotive force element (SC ratio 5
The result of -1) was standardized and described.

[0201]

[Table 5] From the results in Table 5, the photovoltaic element of Example 5 (SC Ex 5)
Was found to be simultaneously superior in all evaluation results to the photovoltaic element of Comparative Example (SC ratio 5-1).

Example 6 In this example, a substrate for a photovoltaic element of the present invention formed by the same method as in Example 4 was used,
The photovoltaic device shown in FIG. 1 was produced using the multi-chamber separation type forming apparatus shown in FIG.

The forming apparatus 400 of FIG. 4 can perform both the MWPCVD method and the RFPCVD method. Using this, each semiconductor layer was formed on the reflection increasing layer 102.

The manufacturing method will be described below in accordance with the procedure. However, a source gas supply device (not shown) is connected to the forming device of FIG. 3 through a gas introduction pipe. The raw material gas cylinders are all refined to ultra-high purity. As a raw material gas cylinder, a SiH ₄ gas cylinder,
CH ₄ gas cylinder, GeH ₄ gas cylinder, Si ₂ H ₆ gas cylinder, PH ₃ / H ₂ (dilution degree: 0.1%) gas cylinder, B
₂ H ₆ / H ₂ (dilution: 0.2%) gas cylinder, H ₂ gas cylinder, He gas cylinder, SiCl ₂ H ₂ gas cylinder, Si
A H ₄ / H ₂ (dilution: 1%) gas cylinder was connected.

(1) Intermediate layer 199 and light reflecting layer 1 of the present invention
01, the substrate on which the reflection increasing layer 102 is formed is placed on the substrate transfer rail 413 in the load chamber 401, and the load chamber 4 is loaded by a vacuum exhaust pump (not shown).
The inside of the chamber No. 01 was evacuated until the pressure reached about 1 × 10 ⁻⁵ Torr.

(2) The gate valve 406 was opened to carry the wafer into the transfer chamber 402 and the deposition chamber 417 which had been evacuated by a vacuum exhaust pump (not shown) in advance. The back surface of the substrate was brought into close contact with the substrate heating heater 410 to heat it, and the inside of the deposition chamber 417 was evacuated by a vacuum exhaust pump (not shown) until the pressure became about 1 × 10 ⁻⁵ Torr.

(3) After the preparation for film formation is completed as described above, H ₂ gas is introduced into the deposition chamber 417 through the gas introduction pipe 429, and the H ₂ gas flow rate is 300 sccc.
Open the valves 441, 431, 430 so that
It was adjusted with the mass flow controller 436. The conductance valve (not shown) was adjusted so that the pressure in the deposition chamber 417 became 1.1 Torr. The substrate heating heater 410 was set so that the substrate temperature was 350 ° C.

(4) When the substrate temperature is stable, μc
The RF n-type layer 103 made of —Si was formed. μc-S
To form an RF n-type layer made of i, SiH ₄ gas,
PH ₃ / H ₂ gas is introduced into the deposition chamber 417 by the valve 44.
Operate 3, 433, 444, 434 to operate the gas introduction pipe 42
Introduced through 9. At this time, the SiH ₄ gas flow rate is 2 s
The mass flow controllers 438, 436 and 439 were adjusted so that the flow rate of ccm and H ₂ gas was 120 sccm and the flow rate of PH ₃ / H ₂ gas was 190 sccm, and the pressure in the deposition chamber 417 was adjusted to 1.1 Torr. The power of the RF power source 422 is set to 0.06 W / cm ² , and the RF power is introduced into the plasma forming cup 420 to cause glow discharge to start the formation of the RFn-type layer on the substrate and to set the layer thickness of 20 nm. When the RFn type layer is formed, the RF power source is turned off to stop the glow discharge, and the RFn type layer 1
The formation of 03 is completed. Si into the deposition chamber 417
The inflow of H ₄ gas, PH ₃ / H ₂ gas, and H ₂ gas was stopped, and the deposition chamber and the gas pipe were evacuated to 1 × 10 ⁻⁵ Torr.

(5) RFi type layer 15 made of a-Si
1. MWi type layer 104 made of a-SiGe, a-Si
RFi-type layer 161 made of a, RFp made of a-SiC
The mold layer 105 was sequentially formed. First, not shown in advance
Transfer chamber that has been evacuated by a vacuum pump
-403 and i-type layer deposition chamber 418
The tube 407 was opened to transfer the substrate. The back side of the board
The i-type layer deposition chip is heated by being brought into close contact with the heating heater 411.
The chamber 418 is pressurized by a vacuum exhaust pump (not shown).
Is about 1 × 10 ^-FiveIt was evacuated to Torr.

(6) To prepare an RFi type layer,
Heater 411 for heating the substrate so that the temperature becomes 280 ° C.
The valve 46 when the substrate is sufficiently heated.
Gradually open 4, 454, 450, 463, 453,
Si₂H₆Gas, H₂Gas through the gas introduction pipe 449 i
It was made to flow into the mold layer deposition chamber 418. At this time, S
i ₂H₆Gas flow rate is 4 sccm, H₂Gas flow is 110s
Each mass flow controller 4 to be ccm
Adjusted at 59, 458. i-type layer deposition chamber 418
The pressure inside is set to 0.6 Torr,
Adjusted the opening of the dactance valve. Next, RF power source 4
24 to 0.007 W / cm²Set the bias bar to 42
8 to generate glow discharge, and shutter 427
Starting the formation of the i-type layer on the RF n-type layer by opening
When an i-type layer having a layer thickness of 10 nm was produced, RF glow was emitted.
Turn off the power, turn off the output of the RF power source 424, and turn on the RFi type layer 1
The fabrication of 51 was completed.

The valves 464, 454, 453 and 450 are closed to stop the inflow of Si ₂ H ₆ gas and H ₂ gas into the i-type layer deposition chamber 418 and the i-type layer deposition chamber 418.
The inside and the gas pipe were evacuated to 1 × 10 ⁻⁵ Torr.

(7) To prepare the MWi type layer, the substrate heating heater 411 is controlled so that the temperature of the substrate becomes 380 ° C.
After setting, when the substrate is sufficiently heated, the valve 461,
451, 450, 462, 452, 463, 453 were gradually opened, and SiH ₄ gas, GeH ₄ gas, and H ₂ gas were caused to flow into the i-type layer deposition chamber 418 through the gas introduction pipe 449.

At this time, the SiH ₄ gas flow rate was 48 scc
m, GeH ₄ gas flow rate is 45 sccm, H ₂ gas flow rate is 1
The mass flow controllers 456, 457, and 458 were adjusted to 80 sccm. The pressure inside the i-type layer deposition chamber 418 was adjusted to 6 mTorr by adjusting the opening of a conductance valve (not shown). Next, the RF power source 424 was set to 0.30 W / cm ² and applied to the bias rod 428. After that, the power of a μW power source (2.45 GHz) (not shown) is set to 0.09 W / cm ² , and μW power is introduced into the i-type layer deposition chamber 418 through the waveguide 426 and the microwave introduction window 425, The glow discharge is caused to occur and the shutter 427 is opened to start the preparation of the MWi type layer on the RFi type layer, and the layer thickness of 0.1
When the 7 μm i-type layer was formed, μW glow discharge was stopped, the output of the bias power source 424 was turned off, and the MWi-type layer 10 was formed.
4 was completed. The valves 451, 452, 453 are closed to stop the inflow of SiH ₄ gas, GeH ₄ gas, and H ₂ gas into the i-type layer deposition chamber 418, and the inside of the i-type layer deposition chamber 418 and the gas pipe are set to 1 × 10. ^-5 Tor
It was evacuated to r.

(8) To prepare an RFi type layer,
Heater 411 for heating the substrate so that the temperature becomes 250 ° C.
The valve 46 when the substrate is sufficiently heated.
Gradually open 4, 454, 450, 463, 453,
Si₂H₆Gas, H₂Gas through the gas introduction pipe 449 i
It was made to flow into the mold layer deposition chamber 418. At this time, S
i ₂H₆Gas flow rate is 3.5 sccm, H₂Gas flow rate is 11
Each mass flow controller to be 0 sccm
Adjusted with -459 and 458. i-type layer deposition chamber 4
The pressure in 18 is not shown so that it becomes 0.5 Torr.
The conductance valve opening was adjusted. Next, RF
Source 424 at 0.007 W / cm²Set to a bias rod
428 to generate a glow discharge, and the shutter 4
By opening 27, the RFi type layer can be formed on the MWi type layer.
RF at the time of starting and forming an i-type layer having a layer thickness of 20 nm
Stop glow discharge, turn off output of RF power supply 424, turn off RF
The production of the i-type layer 161 was completed. Valves 464, 454,
The i-type layer deposition chamber 418 is closed by closing 453 and 450.
Si into₂H₆Gas, H₂Stop the inflow of gas, i-type layer stack
1 × 10 in the product chamber 418 and gas pipe^-FiveT
Evacuated to orr.

(9) RF p-type layer 10 made of a-SiC
5 is formed, the transfer chambers 404 and p are evacuated by a vacuum exhaust pump (not shown) in advance.
The gate valve 408 was opened into the mold layer deposition chamber 419 to transfer the substrate. The back surface of the substrate is brought into close contact with the heater 412 for heating the substrate and heated, and the p-type layer deposition chamber 419
The inside pressure is about 1 × 10 ^-5 by a vacuum exhaust pump (not shown).
It was evacuated to Torr.

The substrate is heated so that the temperature of the substrate becomes 230 ° C.
Set the heater for heat 412 and make sure that the substrate temperature is stable.
By the way, H₂Gas, SiH_Four/ H₂Gas, B₂H₆/ H₂gas,
CH _FourA gas is introduced into the deposition chamber 419 through a valve 481;
471, 470, 482, 472, 483, 473, 4
Operate 84, 474 and introduce through gas introduction pipe 469
did. At this time, H₂Gas flow rate is 70 sccm, SiH_Four/
H₂Gas flow rate is 2 sccm, B₂H₆/ H₂Gas flow rate is 10
sccm, CH_FourGas flow rate should be 0.2 sccm
Mass flow controllers 476, 477, 478,
The pressure in the deposition chamber 419 is 1.
Conductance valve not shown so as to be 7 Torr
Adjusted the opening. The power of the RF power source 423 is 0.07W
/ Cm²Set to RF on the plasma forming cup 421.
Introduce electric power to cause glow discharge and RF on the i-type layer
Start the formation of the p-type layer and form the RF p-type layer with a layer thickness of 10 nm.
Turn off the RF power to stop glow discharge,
The formation of the RF p-type layer 105 is completed.

Valves 472, 482, 473, 483,
474, 484, 471, 481, 470 are closed and SiH ₄ / H ₂ gas into the p-type layer deposition chamber 419, B ₂
The inflow of H ₆ / H ₂ gas, CH ₄ gas, and H ₂ gas was stopped, and the inside of the p-type layer deposition chamber 419 and the gas pipe was set to 1 × 10 ^−5.
Evacuated to Torr.

(10) Unload chamber 40 evacuated in advance by a vacuum exhaust pump (not shown)
5, the gate valve 409 is opened to transfer the substrate, a leak valve (not shown) is opened, and the unload chamber 405 is opened.
Leaked.

(11) ITO having a layer thickness of 70 nm was vacuum-deposited on the RF p-type layer 105 as a transparent conductive layer 112 by a vacuum vapor deposition method.

(12) A mask having comb-shaped holes is placed on the transparent conductive layer 112, and Cr (40 nm) / Ag (100
0nm) / Cr (40nm) comb-shaped collector electrode 1
13 was vacuum deposited by the vacuum deposition method.

Thus, the fabrication of the photovoltaic element of this example was completed. We decided to call this photovoltaic element (SC Ex 6).

(Comparative Example 6-1) In this example, the ZnO intermediate layer 199 was not formed, the Ag light reflecting layer 101 was formed, and then the support temperature was not cooled to 100 ° C. or lower.
The difference from the sixth embodiment is that the reflection increasing layer 102 is formed.
Other points were the same as in Example 6. The photovoltaic element of this example is called (SC ratio 6-1).

The above-mentioned two types of photovoltaic elements, that is, (SC Ex 6) and (SC Ratio 6-1), were produced in 6 pieces each. Table 5 shows the results of a bending peel test for examining the environmental resistance characteristics of each of these photovoltaic elements. Also, the initial photoelectric conversion efficiency (photovoltaic power / incident light power)
The results of evaluation of various characteristics of are also shown.

In the bending peeling test, each photovoltaic element substrate was subjected to a high temperature and high humidity atmosphere (temperature 80 ° C., humidity 85%).
Bending test for 30 hours
Repeat 10 times, further drop a weight of 10 kg from the height of 50 cm to the bent portion 13 times, and observe the peeling condition on the substrate with a Hitachi SEM (model number: S-4500, magnification: 50,000 times). It was In addition, the characteristics of the initial photoelectric conversion efficiency are as follows:
Installed under 1.5 (100 mW / cm ² ) light irradiation,
It was evaluated by measuring the -I characteristic.

In the results of the bending peeling test shown in Table 6, the mark "◯" indicates that there was no peeling at all, and the mark "X" indicates that there was partial peeling. In addition, the evaluation results regarding the various characteristics of the initial photoelectric conversion efficiency shown in Table 6, that is, the evaluation results of the photoelectric conversion efficiency, the short-circuit current, and the open circuit voltage are the results of the photovoltaic element (SC Ex 6), and Electromotive element (SC ratio 6
The result of -1) was standardized and described.

[0226]

[Table 6] From the results in Table 6, the photovoltaic element of Example 6 (SC Ex 6)
Was found to be simultaneously superior to the photovoltaic device of Comparative Example (SC ratio 6-1) in all evaluation results.

(Embodiment 7) In this embodiment, first, by using the multi-chamber separation type forming apparatus shown in FIG. 3, the photovoltaic element substrate 290 shown in FIG. On which each layer of 299, 201 and 202 is formed)
Was produced. Next, the photovoltaic element substrate 290 was used to fabricate the photovoltaic element shown in FIG. 2 using the roll-to-roll system forming apparatus shown in FIG.

The preconditions for the method of manufacturing the photovoltaic element substrate will be described below. A raw material gas supply device (not shown) is connected to the forming device of FIG. 3 through a gas introduction pipe. The raw material gas cylinders are all refined to ultra-high purity. As the source gas cylinder, an H ₂ gas cylinder, an Ar gas cylinder, and a He gas cylinder were connected.
ZnO and Ag were used as targets, and they were arranged so that they could be sputtered in vacuum.

As the support, a thickness of 0.5 mm, 50 ×
Using a 50 mm ² stainless steel plate, ultrasonic cleaning was performed with acetone and isopropanol, and dried with warm air. A DC power source 325 was connected as a sputtering power source, and a ZnO intermediate layer 299 was formed by using a DC magnetron sputtering method.

In the following, a method for manufacturing a photovoltaic device substrate will be described according to the procedure. (1) The washed support 390 (100 in FIG. 1) is arranged on the support transfer rail 313 in the load chamber 301, and the pressure inside the load chamber 301 is about 1 × 10 ⁻ by a vacuum exhaust pump (not shown). ^It was evacuated to ⁵ Torr.

(2) The gate valve 306 was opened to carry into the transfer chamber 302 and the deposition chamber 320, which had been evacuated by a vacuum exhaust pump (not shown) in advance. The back surface of the support 390 is provided with a heater 3 for heating the support.
10 is heated to a temperature of 25 ° C./S, the temperature of the support is set to 250 ° C., and the pressure inside the deposition chamber 320 is set to about 3 × 10 ⁻⁶ Torr by a vacuum exhaust pump (not shown).
It was evacuated until.

(3) Ar gas is supplied from the gas introduction pipe 324 to 4
Introduce 5 sccm, adjust the pressure to 4 mTorr with a conductance valve (not shown), apply a current to the toroidal coil 323, and sputter power sources 325 to 380.
V DC power was applied to generate Ar plasma.

(4) When the target shutter 326 was opened and the intermediate layer 299 of ZnO having a layer thickness of 0.012 μm was formed on the surface of the stainless steel plate, the target shutter 326 was closed to extinguish the plasma.

(5) After raising the heater 310 for heating the support and lowering the temperature of the support to 100 ° C. or less at a temperature decreasing speed of 20 ° C./S in a He gas atmosphere as a gas for cooling the support, a vacuum not shown in advance is prepared. The gate valve 307 was opened to carry into the transfer chamber 303 and the deposition chamber 330, which had been evacuated by the exhaust pump. The back surface of the support 390 is brought into close contact with the support heating heater 311 and heated at a temperature rising speed of 15 ° C./S to raise the support temperature to 2
The temperature was raised to 90 ° C. and the inside of the deposition chamber 330 was evacuated by a vacuum exhaust pump (not shown) until the pressure became about 2 × 10 ⁻⁶ Torr.

(6) Ar gas of 3 is supplied from the gas introduction pipe 334.
5 sccm is introduced, the pressure is adjusted to 4 mTorr by a conductance valve (not shown), a current is supplied to the toroidal coil 333, and a sputtering power supply 335 to 380 is supplied.
V DC power was applied to generate Ar plasma. Next, the target shutter 336 is opened, and the Ag light reflection layer 20 having a layer thickness of 0.7 μm is formed on the surface of the intermediate layer 299 of ZnO.
When 1 was formed, the target shutter 336 was closed to extinguish the plasma.

(7) The heater 311 for heating the support is raised, and the temperature of the support is lowered to 100 ° C. or less at a temperature lowering speed of 15 ° C./S in a He gas atmosphere as a gas for cooling the support, and then again not shown in advance. The gate valve 307 was opened to carry into the transfer chamber 302 and the deposition chamber 320, which had been evacuated by the vacuum pump.
The back surface of the support 390 is brought into close contact with the support heating heater 310 and heated at a temperature rising rate of 15 ° C./S to raise the support temperature to 315 ° C., and the pressure inside the deposition chamber 320 is reduced to about 3 by a vacuum exhaust pump (not shown). The chamber was evacuated to × 10 ^-6 Torr.

(8) Ar gas 4
Introduce 5 sccm, adjust the pressure to 4 mTorr with a conductance valve (not shown), apply a current to the toroidal coil 323, and sputter power sources 325 to 385.
V DC power was applied to generate Ar plasma. Next, the target shutter 326 is opened and the Ag light reflecting layer 2 is opened.
01 reflection enhancing layer 20 of ZnO having a thickness of 1.5 μm on the surface
When 2 was formed, the target shutter 326 was closed to extinguish the plasma.

(9) Raise the heater 310 for heating the support, lower the temperature of the support to 100 ° C. or less at a temperature lowering speed of 16 ° C./S in a He gas atmosphere as a gas for cooling the support, and then evacuate in advance (not shown). The gate valves 307 and 308 were opened and transferred into the transfer chamber 303 and the unload chamber 304 that had been evacuated by a pump. The fabrication of the photovoltaic device substrate of this example was completed as described above. This photovoltaic element substrate is called (S Ex 7).

The preconditions for the method of manufacturing a photovoltaic element will be described below. Using the substrate for photovoltaic device manufactured in the above steps (1) to (9) and using the roll-to-roll type forming apparatus shown in FIG. 4, the triple photovoltaic shown in FIG. A device was produced.

(10) The substrate on which the intermediate layer 299, the light reflection layer 201, and the reflection increasing layer 202 described above are formed is placed on the substrate transfer rail 413 in the load chamber 401, and a vacuum exhaust pump (not shown) is used. The inside of the load chamber 401 was evacuated to a pressure of about 1 × 10 ⁻⁵ Torr.

(11) Transfer chambers 402 and 4 which have been evacuated by a vacuum exhaust pump (not shown) in advance
03 and the gate valve 40 into the deposition chamber 418
6, 407 were opened and conveyed. The back surface of the substrate is brought into close contact with the substrate heating heater 411 to heat the substrate, and the deposition chamber 41 is heated.
The inside of 8 has a pressure of about 1 × 10 by a vacuum exhaust pump (not shown).
^It was evacuated to ^-5 Torr.

(12) After the preparation for film formation is completed as described above, H ₂ gas is introduced into the deposition chamber 417 through the gas introduction pipe 429, and the H ₂ gas flow rate is 500 sc.
cm, the valves 441, 431, and 430 were opened, and adjusted by the mass flow controller 436. The pressure inside the deposition chamber 417 was adjusted to 1.3 Torr by a conductance valve (not shown). The substrate heating heater 410 was set so that the substrate temperature was 350 ° C.

(13) When the substrate temperature is stable, μ
An RFn type layer 203 made of c-Si was formed. μc-
In order to form the RFn-type layer made of Si, SiH ₄ gas and PH ₃ / H ₂ gas were introduced into the deposition chamber 417 through the gas introduction pipe 429 by operating the valves 443, 433, 444 and 434. At this time, SiH ₄ gas flow rate is ₂ sccm, H ₂ gas flow rate is 100 sccm, PH ₃ / H
_The mass flow controllers 438, 436, and 439 were adjusted so that the ₂ gas flow rate was 200 sccm, and the pressure in the deposition chamber 417 was adjusted to 1.3 Torr. The power of the RF power source 422 is 0.05 W / cm ²
And RF power is introduced into the plasma forming cup 420 to cause glow discharge, start forming an RFn type layer on the substrate, and turn off the RF power source when the RFn type layer having a layer thickness of 20 nm is formed. The glow discharge was stopped, and the formation of the RFn-type layer 203 was completed. S into the deposition chamber 417
The inflow of iH ₄ gas, PH ₃ / H ₂ gas, and H ₂ gas was stopped, and the inside of the deposition chamber and the gas pipe were evacuated to 1 × 10 ⁻⁵ Torr.

(14) By the same method as in Example 2, a
-Si RFi type layer 251, a-SiGe MWi type layer 204, a-Si RFi type layer 26
1. RF p-type layer 205 made of a-SiC, μc-Si
RF n-type layer 206 made of a-Si, RFi-type layer 252 made of a-Si, MWi-type layer 207 made of a-SiGe, a
RFi type layer 262 made of -Si, RFp type layer 208 made of a-SiC, and RFn type layer 20 made of μc-Si.
9. An RFi type layer 210 made of a-Si and an RFp type layer 211 made of a-SiC were sequentially formed.

(15) As a transparent conductive layer 212, ITO having a layer thickness of 70 nm was vacuum-deposited on the RF p-type layer 211 by a vacuum deposition method. (16) Place a mask having comb-shaped holes on the transparent conductive layer 212, and perform Cr (40 nm) / Ag (1000 nm) / C
A comb-shaped collector electrode 213 made of r (40 nm) was vacuum-deposited by a vacuum deposition method.

The fabrication of the photovoltaic element of this example was completed above. We decided to call this photovoltaic element (SC Ex 7). Table 9 shows RFn type layer, RFi type layer, MWi type layer, R
Conditions for forming the Fp type layer.

(Comparative Example 7-1) In this example, the ZnO intermediate layer 299 was not formed, the Ag light reflecting layer 201 was formed, and the support temperature was not cooled to 100 ° C. or lower.
The difference from Example 7 is that the reflection increasing layer 202 is formed.
The other points were the same as in Example 7. The photovoltaic element of this example is called (SC ratio 7-1).

The above-mentioned two types of photovoltaic elements, that is, (SC Ex 7) and (SC Ratio 7-1), were produced in 6 pieces each. Table 7 shows the results of a bending peel test for examining the environmental resistance of each of these photovoltaic elements. Also, the initial photoelectric conversion efficiency (photovoltaic power / incident light power)
The results of evaluations of various characteristics and photodegradation characteristics are also shown.

In the bending peel test, each photovoltaic element substrate was subjected to a high temperature and high humidity atmosphere (temperature 80 ° C., humidity 85%).
After leaving it in the environment of 250 hours, the bending test is performed for 30 hours.
Repeat 10 times, drop a weight of 10 kg from the height of 50 cm on the bent portion 10 times, and observe the peeling condition on the substrate with Hitachi SEM (model number: S-4500, magnification: 50,000 times). It was In addition, the characteristics of the initial photoelectric conversion efficiency are as follows:
Installed under 1.5 (100 mW / cm ² ) light irradiation,
It was evaluated by measuring the -I characteristic. Further, the photo-degradation property is a result of evaluating the photoelectric conversion efficiency of a photovoltaic element having a temperature of 50 ° C. after irradiation for 1000 hours under 1 sun of 100 mW / cm ² .

In the results of the bending peeling test shown in Table 7, the mark ◯ indicates that there was no peeling, and the mark x indicates that there was partial peeling. In addition, the evaluation results regarding the various characteristics of the initial photoelectric conversion efficiency shown in Table 7, that is, the evaluation results of the photoelectric conversion efficiency and the short-circuit current, and the photodegradation characteristics are the results of the photovoltaic element (SC Ex 7). The results of the photovoltaic device (SC ratio 7-1) are shown as standardized.

[0251]

[Table 7] From the results in Table 7, the photovoltaic element of Example 7 (SC Ex 7)
Was found to be simultaneously superior to the photovoltaic device of Comparative Example (SC ratio 7-1) in all evaluation results.

Example 8 In this example, the triple photovoltaic element shown in FIG. 2 was produced using the roll-to-roll type forming apparatus shown in FIGS.

The support has a length of 300 m and a width of 30 c.
A strip-shaped stainless sheet having a thickness of m and a thickness of 0.2 mm was used.
FIG. 6 is a schematic view of a continuous device for forming a photovoltaic device substrate according to the present invention using a roll-to-roll method. FIG.
It is a schematic diagram of a continuous formation device of a photovoltaic element using a roll-to-roll method.

Hereinafter, a method for manufacturing a photovoltaic element substrate will be described. In the apparatus for continuously forming a substrate for a photovoltaic element shown in FIG. 6, a support delivery chamber 610, a plurality of deposition chambers 611 to 614, and a support winding chamber 684 are sequentially arranged, and a separation passage is provided between them. 615, 616, 61
7, 618, and 619 are connected, and each deposition chamber has an exhaust port so that the inside can be evacuated. The strip-shaped support body 621 is wound up from the support body feed-out chamber to the support body winding chamber through these deposition chambers and separation passages.
At the same time, the gas can be introduced from the gas inlets of the deposition chambers and the separation passages, and the gas can be exhausted from the respective exhaust ports to form the respective layers. Deposition chamber 61
No. 2 has an intermediate layer of ZnO, and Ag has been deposited in the deposition chamber 613.
And a reflection enhancing layer made of ZnO in the deposition chamber 614. Each deposition chamber has halogen lamp heaters 640, 641, 64 for heating the support from the back.
2, 643 are installed inside, and are heated or heated to a predetermined temperature in each deposition chamber. In addition, separation passages 617, 618,
619 has the temperature lowering function of the present invention.

A DC magnetron sputtering method is performed in the deposition chamber 612, Ar gas is introduced from the gas inlet 632, and ZnO is used as the target 650. In the deposition chamber 613, the DC magnetron sputtering method is performed,
Ar gas is introduced from the gas inlet 634, and Ag is used as the target 660. In the deposition chamber 614, a DC magnetron sputtering method or an RF magnetron sputtering method is performed, Ar gas is introduced from a gas inlet 636, and ZnO is used as a target 670. After forming the substrate for photovoltaic element of the present invention under predetermined conditions (Table 10), the substrate is wound into the support winding chamber 684.

Hereinafter, a method for manufacturing a photovoltaic element will be described. Using the roll-to-roll type photovoltaic device forming apparatus shown in FIG. 5, the triple type photovoltaic device shown in FIG. 2 was formed under the triple type photovoltaic device forming conditions shown in Table 11.

A load chamber 5010 for introducing a sheet-shaped substrate having the substrate for photovoltaic element of the present invention is introduced.
Set to. The sheet-shaped base hill was connected to the sheet winding jig of the unload chamber 5150 through the whole stacking chamber and all gas gates. Each deposition chamber was set to 10 ^-3 To with an exhaust device (not shown).
It exhausted to rr or less. Mixing devices 5024, 5034, 5044, 5054, 5064 for forming each deposited film,
5074, 5084, 5094, 5104, 5114,
A desired source gas was supplied to each deposition chamber from 5124, 5134, and 5144. Each gas gate 5201, 5202,
5203, 5204, 5205, 5206, 5207,
5208, 5209, 5210, 5211, 5212,
Gas was supplied to 5213 and 5214 from each gate gas supply device. Heat the substrate with the heater for heating the substrate of each deposition device, adjust the degree of vacuum by adjusting the degree of opening and closing of the exhaust valve of each exhaust device, and after the substrate temperature and degree of vacuum have stabilized, start transporting the sheet substrate. , RF for plasma generation in each deposition chamber
Electric power and MW (frequency: 2.45 GHz) electric power were supplied. As described above, the pi of FIG.
A triple type photovoltaic device was formed by stacking three n structures.

Next, on the RF p-type layer 211, ITO having a layer thickness of 70 nm was vacuum-deposited by a vacuum deposition method as a transparent conductive layer 212.

Next, a mask having comb-shaped holes is placed on the transparent conductive layer 212, and Cr (40 nm) / Ag (1000 n
m) / Cr (40 nm) comb-shaped current collecting electrode 213
Was vacuum deposited by a vacuum deposition method.

The fabrication of the photovoltaic element of this example was completed above. This photovoltaic element is called (SC Ex 8). Table 10 shows the formation conditions of the photovoltaic device substrate of this example. Table 11 shows RFn type layer, RFi type layer, MW
Conditions for forming the i-type layer and the RFp-type layer.

(Comparative Example 8-1) In this example, the ZnO intermediate layer 299 was not formed, and after the Ag light reflecting layer 201 was formed, the support temperature was not cooled to 100 ° C. or lower and ZnO was not used.
The difference from Example 8 is that the reflection increasing layer 202 is formed.
The other points were the same as in Example 8. The photovoltaic element of this example is called (SC ratio 8-1).

The above-mentioned two types of photovoltaic elements, that is, (SC Ex 8) and (SC Ratio 8-1), were produced in 7 pieces each. Table 8 shows the results of a bending peel test for examining the environmental resistance of each of these photovoltaic elements. Also, the initial photoelectric conversion efficiency (photovoltaic power / incident light power)
The results of evaluations of various characteristics and photodegradation characteristics are also shown.

In the bending peeling test, each photovoltaic element substrate was subjected to a high temperature and high humidity atmosphere (temperature: 82 ° C., humidity: 85%).
After leaving it in the environment of 250 hours, the bending test is performed for 30 hours.
Repeat 10 times, drop a weight of 10 kg from the height of 50 cm on the bent portion 10 times, and observe the peeling condition on the substrate with Hitachi SEM (model number: S-4500, magnification: 50,000 times). It was In addition, the characteristics of the initial photoelectric conversion efficiency are as follows:
Installed under 1.5 (100 mW / cm ² ) light irradiation,
It was evaluated by measuring the -I characteristic. Further, the photo-deterioration characteristic is the result of evaluating the photoelectric conversion efficiency of a photovoltaic element having a temperature of 52 ° C. after irradiation for 1200 hours under 1 sun of 100 mW / cm ² .

In the results of the bending peeling test shown in Table 8, the mark ◯ indicates that there was no peeling at all, and the mark x indicates that there was partial peeling. In addition, the evaluation results regarding the various characteristics of the initial photoelectric conversion efficiency shown in Table 8, that is, the evaluation results of the photoelectric conversion efficiency and the short-circuit current, and the photodegradation characteristics are the results of the photovoltaic element (SC Ex 8), The results of the photovoltaic element (SC ratio 8-1) are shown as standardized.

[0265]

[Table 8] From the results in Table 8, the photovoltaic element of Example 8 (SC Ex 8)
Was found to be simultaneously superior in all evaluation results to the photovoltaic element of Comparative Example (SC ratio 8-1).

(Embodiment 9) In this embodiment, the temperature rising speed at the time of forming the intermediate layer, the light reflection layer and the reflection increasing layer is 2
The effect on the initial characteristics of photoelectric conversion and the like was examined by changing the temperature in the range of ° C / sec to 150 ° C / sec. ZnO was used as a target for forming the intermediate layer.

Table 12 shows the conditions for forming the substrate for the photovoltaic element,
Table 13 shows the production conditions for the triple photovoltaic element. Also in this example, as in the case of Example 8, by using the continuous forming apparatus for a photovoltaic element substrate shown in FIG. 6 and the continuous forming apparatus for photovoltaic elements shown in FIG. An electromotive force element was produced. The other points were the same as in Example 8.

Table 14 shows the bending and peeling test, the photoelectric conversion efficiency, the short-circuit current, and the photovoltaic device manufactured in this example.
And the results of evaluation of photodegradation characteristics. The evaluation results of each property in Table 14 are shown by standardizing the measurement results obtained when the temperature rising speed is 2 ° C./sec. The mark x indicates 1.0 or more and less than 1.4, the mark Δ indicates 1.4 or more and less than 1.8, and the mark ◯ indicates 1.8 or more.

From Table 14, the temperature rising speed at the time of forming the photovoltaic element substrate is 10 in the bending and peeling test of the photovoltaic element, the photoelectric conversion efficiency, the short-circuit current, and the photodegradation property.
It was found that a suitable range is from ° C / sec to 100 ° C / sec.

(Embodiment 10) In this example, the temperature lowering speed at the time of forming the intermediate layer, the light reflecting layer and the reflection increasing layer was
The influence on the initial characteristics of photoelectric conversion and the like was examined by changing the temperature in the range of 0.2 ° C / sec to 90 ° C / sec. ZnO was used as a target for forming the intermediate layer.

Table 15 shows the conditions for forming a substrate for a photovoltaic element,
Table 16 shows the production conditions for the triple photovoltaic element. Also in this example, as in the case of Example 8, by using the continuous forming apparatus for a photovoltaic element substrate shown in FIG. 6 and the continuous forming apparatus for photovoltaic elements shown in FIG. An electromotive force element was produced. The other points were the same as in Example 8.

Table 17 shows the bending and peeling test, the photoelectric conversion efficiency, the short-circuit current, and the photovoltaic device manufactured in this example.
And the results of evaluation of photodegradation characteristics. The evaluation results of each characteristic in Table 17 are shown by standardizing the measurement results obtained when the cooling rate is 0.2 ° C./sec. X is 1.0
More than 1.4 but less than 1.4, more than 1.4 but less than 1.8
The mark indicates 1.8 or more.

From Table 17, the temperature decreasing speed at the time of forming the substrate for the photovoltaic element is 1 ° C. in the bending and peeling test of the photovoltaic element, the photoelectric conversion efficiency, the short-circuit current and the photodegradation property.
It has been found that a suitable range is from / sec to 50 ° C / sec.

(Embodiment 11) In this example, the influence on the initial characteristics of photoelectric conversion was investigated by changing the film thickness of the intermediate layer in the range of 0.0002 μm to 0.2 μm. ZnO was used as a target for forming the intermediate layer.

Table 18 shows the conditions for forming a substrate for a photovoltaic element,
Table 19 shows the production conditions for the triple photovoltaic element. Also in this example, as in the case of Example 8, by using the continuous forming apparatus for a photovoltaic element substrate shown in FIG. 6 and the continuous forming apparatus for photovoltaic elements shown in FIG. An electromotive force element was produced. The other points were the same as in Example 8.

Table 20 shows the bending and peeling test, the photoelectric conversion efficiency, the short-circuit current, and the photovoltaic element manufactured in this example.
And the results of evaluation of photodegradation characteristics. The evaluation results of each characteristic in Table 20 are shown by standardizing the measurement results obtained when the thickness of the intermediate layer was 0.0002 μm. The mark x indicates 1.0 or more and less than 1.4, the mark Δ indicates 1.4 or more and less than 1.8, and the mark ◯ indicates 1.8 or more.

From Table 20, the thickness of the intermediate layer at the time of forming the substrate for the photovoltaic element is 0.0 in the bending and peeling test of the photovoltaic element, the photoelectric conversion efficiency, the short-circuit current, and the photodegradation property.
It was found that a suitable range is 01 μm to 0.1 μm.

[0278]

[Table 9]

[0279]

[Table 10]

[0280]

[Table 11]

[0281]

[Table 12]

[0282]

[Table 13]

[0283]

[Table 14]

[0284]

[Table 15]

[0285]

[Table 16]

[0286]

[Table 17]

[0287]

[Table 18]

[0288]

[Table 19]

[0289]

[Table 20]

[0290]

As described above, according to the present invention,
A method for forming a photovoltaic device that can prevent excessive oxidation of a reflective layer is obtained. As a result, a high light reflectance can be realized by the combination of the reflective layer and the reflection increasing layer. Furthermore, when a semiconductor layer is formed on such a reflective layer and a reflection increasing layer, a photovoltaic element with high conversion efficiency can be obtained.

Further, according to the present invention, the formation of the photovoltaic element capable of improving the adhesion between the reflection layer and the reflection increasing layer by suppressing the oxidation of the surface of the reflection layer made of metal as much as possible. A method is obtained. As a result, by making the oxide layer thinner, strain can be reduced and stress in the reflection layer and the reflection enhancement layer can be reduced. Due to these improvements, a method for forming a photovoltaic device having improved environment resistance can be obtained.

Further, according to the present invention, there can be obtained a method for forming a photovoltaic element, in which the adhesion between the support and the reflection layer is improved, and in particular the adhesion to mechanical strain such as bending is improved.

(Claim 2) According to the invention of claim 2, the formation of a photovoltaic element in which the surface shape of the reflection layer can be made into a discontinuous surface state having unevenness and having a high light confinement effect. A method is obtained.

(Claim 3) According to the invention according to claim 3, a photovoltaic element capable of forming the surface shape of the reflection increasing layer into a continuous surface state having a high reflection efficiency and a uniform layer thickness. Can be obtained.

(Claim 4) According to the invention of claim 4, thermal strain due to temperature change of the support is suppressed, the photovoltaic element is separated from the support, and the series resistance of the photovoltaic element is reduced. It is possible to obtain a method for forming a photovoltaic element that can suppress an increase in

(Claim 5) According to the invention of claim 5, thermal strain due to temperature change of the support is suppressed, the photovoltaic element is separated from the support, and the series resistance of the photovoltaic element is reduced. It is possible to obtain a method for forming a photovoltaic element that can suppress an increase in

(Claim 6) According to the invention of claim 6, the oxidation of the surface of the reflective layer can be suppressed as much as possible, the temperature drop of the support can be maintained, and at the same time the photovoltaic element A method for forming a photovoltaic device that can suppress series resistance is obtained.

(Claim 7) According to the invention of claim 7, it is possible to improve the adhesion between the support and the reflection layer and at the same time suppress the increase in series resistance of the photovoltaic element.
A method of forming a photovoltaic device is obtained.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view of a single photovoltaic element to which a hydrogen plasma treatment method according to the present invention is applied.

FIG. 2 is a schematic cross-sectional view of a triple type photovoltaic device to which the hydrogen plasma processing method according to the present invention is applied.

FIG. 3 is a schematic view of a multi-chamber separation type photovoltaic device substrate continuous forming apparatus according to the present invention.

FIG. 4 is a schematic view of an apparatus for continuously forming multi-chamber separation type photovoltaic elements according to the present invention.

FIG. 5 is a schematic view of a continuous photovoltaic device forming apparatus using a roll-to-roll method according to the present invention.

FIG. 6 is a schematic view of a continuous forming apparatus for a photovoltaic device substrate using a roll-to-roll method according to the present invention.

[Explanation of symbols]

100, 200 support, 101, 201 reflective layer (or transparent conductive layer), 102, 202 reflection increasing layer (or antireflection layer), 103, 203 first n-type layer (or p-type layer), 104, 204 First i-type layer, 105, 205 First p-type layer (or n-type layer), 112, 212 Transparent conductive layer (or conductive layer), 113, 213 Current collecting electrode, 151, 251 First n / i buffer layer, 161, 261 first p / i buffer layer, 190, 290 substrate, 199, 299 intermediate layer, 206 second n-type layer (or p-type layer), 207 second i-type layer, 208 Second p-type layer (or n-type layer), 209 third n-type (or p-type layer), 210 third i-type layer, 211 third p-type layer (or n-type layer), 252 second N / i buffer layer, 262 second p i buffer layer, 301 load lock chamber, 302, 303 transfer chamber, 304 unload chamber, 306 to 308 gate valve, 310, 311 support heating heater, 313 support transfer rail, 320 intermediate layer and reflection increasing layer deposition Chamber, 321, 331 target, 322, 332 target electrode, 323, 333 toroidal coil, 324, 334 gas introduction tube, 325, 335 sputter power supply, 326, 336 target shutter, 330 light reflection layer deposition chamber, 390 support, 400 Multi-chamber separation type deposition apparatus, 401 load lock chamber, 402 n-type layer (or p-type layer) transfer chamber, 403 MW-i or RF-i layer transfer chamber, 404 p-type layer (or n-type layer) transfer chamber , 405 unload chamber, 406-409 gate valve, 410 12 Substrate heating heater, 413 Substrate transportation rail, 417 n-type layer (or p-type layer) deposition chamber, 418 MW-i or RF-i layer deposition chamber, 419 p-type layer (or n-type layer) deposition Chamber, 420, 421 RF introducing cup, 422, 423 RF power source, 424 bias applying power source, 425 MW introducing window, 426 MW introducing waveguide, 427 MW-i deposition shutter, 428 bias electrode, 429, 449, 469 gas supply pipes, 430-434, 441-444, 450-455, 4
61-465, 470-474, 481-484 stop valve, 436-439, 456-460, 476-479 mass flow controller, 490 substrate holder, 5010 load chamber for sheet-like substrate introduction, 5011, 5021, 5031, 5041, 5051,
5061, 5071, 5081, 5091, 5101,
5111, 5121, 5131, 5141, 5151
Exhaust pipe, 5012, 5022, 5032, 5052, 5062,
5072, 5082, 5102, 5112, 5122,
5132, 5142, 5152 exhaust pump, 5020 first n-type layer deposition chamber, 5023, 5033, 5053, 5063, 5073,
5083, 5103, 5113, 5123, 5133,
5143 RF supply coaxial cable, 5024, 5034, 5054, 5064, 5074,
5084, 5104, 5114, 5124, 5134,
5144 RF power supply, 5025, 5035, 5045, 5055, 5075,
5065, 5085, 5095, 5105, 5115,
5125, 5135, 5145 Source gas supply pipe, 5026, 5036, 5046, 5056, 5076,
5066, 5086, 5096, 5106, 5116,
5126, 5136, 5146 Mixing device, 5030 1st RF-i layer (n / i) deposition chamber, 5040 1st MW-i layer deposition chamber, 5042, 5092 Exhaust pump (with diffusion pump), 5043, 5093 MW Introducing waveguide, 5044, 5094 MW power source, 5050 First RF-i layer (p / i) deposition chamber, 5060 First p-type layer deposition chamber, 5070 Second n-type layer deposition chamber, 5080 2 RF-i layer (n / i) deposition chamber, 5090 2nd MW-i layer deposition chamber, 5100 2nd RF-i layer (p / i) deposition chamber, 5110 2nd p-type layer deposition chamber , 5120 third n-type layer deposition chamber, 5130 RF-i layer deposition chamber, 5140 third p-type layer deposition chamber, 5150 unload chamber, 5201-5214 gas gate, 5301-5314 gas to gas gate Supply pipe, 5400 sheet feeding jig, 5401 sheet substrate, 5402 sheet winding jig, 610 sheet support feeding chamber, 612 intermediate layer deposition chamber, 613 light reflection layer deposition chamber, 614 reflection increasing layer deposition chamber, 615 to 619 separation passage, 620 delivery roll, 621 sheet-like support, 622 winding roll, 630-632, 634, 636 gas introduction pipe, 633, 635, 637 support cooling gas introduction Tube, 640 to 643 heater for heating support, 650, 660, 670 target, 651, 661, 671 target electrode, 652, 662, 672 toroidal coil, 653, 663, 673 sputter power supply, 684 sheet-like support winding chamber .

Claims (7)

[Claims] 1. An n-type, an i-type, and a p-type in which a silicon atom is contained and a crystal structure is a non-single crystal on a substrate formed by laminating a reflection layer and a reflection increasing layer on a support. In the method for forming a photovoltaic element, wherein the pin structure formed by stacking the semiconductor layers is repeatedly arranged on the substrate at least once, an intermediate layer made of zinc oxide between the support and the reflection layer. A layer is provided, and the reflective layer has a support temperature of 200 to 500.
C., a step β of cooling the support temperature to 100 ° C. or lower after the step α, and a step of depositing the reflection increasing layer at a support temperature of 200 to 400 ° C. after the step β. A method for forming a photovoltaic element, comprising: 2. The method for forming a photovoltaic element according to claim 1, wherein the main component of the reflective layer is silver. 3. The method of forming a photovoltaic element according to claim 1, wherein the main component of the reflection enhancing layer is zinc oxide. 4. The method for forming a photovoltaic element according to claim 1, wherein the rate of decrease of the support temperature in the step β is 1 to 50 ° C./sec. . 5. The method of forming a photovoltaic element according to claim 1, wherein the rate of rise of the support temperature in the step γ is 10 to 100 ° C./sec. . 6. The support cooling gas in the step β is at least one gas selected from hydrogen gas, helium gas, and argon gas, according to any one of claims 1 to 5. A method for forming a photovoltaic element according to item. 7. The method for forming a photovoltaic element according to claim 1, wherein the temperature of the support when depositing the intermediate layer is 30 to 500 ° C.