JP2001244488A - Photovoltaic element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a photovoltaic element suppressing the diffusion of zinc atoms to a semiconductor layer including silicon atoms, suppressing the drop of the transmission factor of a transparent conductive layer including zinc oxide, and suppressing the drop of adhesion force among substrate, the transparent conductive layer including zinc oxide and the semiconductor layer, even if the process of a reduction atmosphere such as a heating processing, an annealing processing and a hydrogen processing is included, in a process where the element is used at a high temperature, at high humidity or for long time or a process after the transparent conductive layer including zinc oxide is formed. SOLUTION: In a photovoltaic element, at least a first transparent conductive layer 101-3, a semiconductor layer 102 including silicon atoms and a second transparent conductive layer 103 are included on a substrate 101-1. At least, the first transparent conductive layer 101-3 of the second transparent conductive layer 103 includes zinc oxide and a layer including silicon oxide is installed in an area which is brought into contact with the transparent conductive layer including zinc oxide in the semiconductor layer 102 including the silicon atoms.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photovoltaic device such as a solar cell or a sensor including a transparent conductive layer containing zinc oxide and a semiconductor layer containing silicon atoms.

[0002]

2. Description of the Related Art Conventionally, a photovoltaic element having a semiconductor layer made of hydrogenated amorphous silicon, hydrogenated amorphous silicon germanium, hydrogenated amorphous silicon carbide, microcrystals thereof, polycrystals, etc. has been known. In order to improve the collection efficiency at a long wavelength, a semiconductor layer provided with a reflective layer on the back surface has been used. Such a reflective layer has a wavelength near the band edge of the semiconductor material where its absorption is reduced, ie, 800
It is desirable to exhibit effective reflection characteristics from nm to 1200 nm. Metals such as gold, silver, copper, and aluminum, and alloys thereof, etc., can sufficiently satisfy this condition.

Further, optical confinement is provided by providing an optically transparent uneven layer in a predetermined wavelength range. Generally, a transparent conductive layer having unevenness between the metal layer and the semiconductor layer is provided. To improve the short-circuit current density Jsc by effectively utilizing the reflected light. Further, the transparent conductive layer prevents deterioration in characteristics due to a shunt path. Further, in order to improve the short-circuit current density Jsc by effectively utilizing incident light, the optical path length of the incident light in the semiconductor layer is increased by providing the uneven transparent conductive layer on the light incident side of the semiconductor. Have been tried.

As an example, “P-lA-15a-SiC / a-Si / a-Si
Ge Multi-Bandgap Stacked Solar Cells With Bandgap
Profiling ”Sannnomiya et al., Technical Digest of t
He International PVSEC-5, Kyoto, Japan, p387, 1990, etc., describe that the combination of a zinc oxide layer with a reflective layer made of silver atoms and an uneven layer achieves an increase in short-circuit current due to the light confinement effect. ing.

[0005]

However, as described above, the transparent conductive layer containing zinc oxide and the photovoltaic device using the same as described above have excellent photoelectric conversion characteristics. When these photovoltaic elements are used in series under low temperature, high humidity, or long-term use, if only a part of them is irradiated for a long time, light Heat treatment, annealing treatment, hydrogen treatment when a potential of the opposite polarity to the potential generated by ordinary light conversion is applied to the non-processed part, or in the process after forming a transparent conductive layer containing zinc oxide In the case of including a process of a reducing atmosphere such as, zinc atoms in zinc oxide diffuse into the semiconductor layer containing silicon atoms, or the transmittance of the transparent conductive layer is reduced, or the transparent conductive layer Due to factors such as adhesion to the layer in contact is lowered, there is a concern that reducing the photoelectric conversion characteristics. In particular, in the case where at least a part of the formation of the semiconductor layer containing silicon atoms is performed through a process in an atmosphere having a large reducing action due to the formation of a crystallized semiconductor layer or the like, there is a particular concern. It was big.

Therefore, the present invention solves the above-mentioned problems,
Under high temperature, high humidity, or long-term use, or when a process after forming a transparent conductive layer containing zinc oxide includes a heat treatment, an annealing process, and a process in a reducing atmosphere such as a hydrogen process. It is another object of the present invention to provide a photovoltaic device having excellent photoelectric conversion characteristics.

[0007]

Means for Solving the Problems The present invention provides at least:
A first transparent conductive layer, a semiconductor layer containing silicon atoms,
In a photovoltaic device including a second transparent conductive layer on a substrate, the first transparent conductive layer and at least one layer of the second transparent conductive layer include zinc oxide, and the silicon atom A photovoltaic element is provided, wherein a layer containing silicon oxide is provided in a region of the semiconductor layer containing silicon oxide in a region in contact with the transparent conductive layer containing zinc oxide.

According to the present invention, there is provided a transparent conductive layer comprising at least one set of a pin junction comprising a p-type semiconductor layer, an i-type semiconductor layer, and an n-type semiconductor layer. A photovoltaic element characterized in that a layer containing silicon oxide is provided between the p-type semiconductor layer or the n-type semiconductor layer closest to the above and the transparent conductive layer containing zinc oxide.

According to the present invention, the semiconductor layer containing silicon atoms includes at least one set of pin junctions composed of a p-type semiconductor layer, an i-type semiconductor layer, and an n-type semiconductor layer. A photovoltaic element, wherein the closest p-type semiconductor layer or n-type semiconductor layer contains silicon oxide as a main component.

The present invention provides a photovoltaic device characterized in that a crystallization process is performed in at least a part of the process of forming the semiconductor layer containing silicon atoms.

It is preferable that the layer containing silicon oxide contains a dopant atom. The oxygen concentration in the silicon oxide,
Preferably, it increases toward the transparent conductive layer containing zinc oxide. It is preferable that the crystallization treatment is at least one of a heating treatment, an annealing treatment, and a hydrogen treatment. A plasma CV in which the semiconductor layer uses a high frequency
Preferably, it was prepared by Method D. Preferably, the semiconductor layer contains a crystal phase.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS As a result of intensive studies to solve the above-mentioned problems, the present inventors have found that at least a first transparent conductive layer, a semiconductor layer containing silicon atoms, a second transparent conductive layer In a photovoltaic element including a layer, the first transparent conductive layer, at least one of the second transparent conductive layers contains zinc oxide, a semiconductor layer containing silicon, the transparent conductive layer containing zinc oxide, A photovoltaic element, particularly a semiconductor layer containing silicon atoms, wherein a layer made of silicon oxide is provided in a region in contact with the p-type semiconductor layer;
Type semiconductor layer, at least one set of pin junctions composed of an n-type semiconductor layer, the p-type semiconductor layer or the n-type semiconductor layer closest to the transparent conductive layer containing the zinc oxide,
A photovoltaic element provided with a layer made of silicon oxide between at least the transparent conductive layer containing zinc oxide and the p-type semiconductor layer or the n-type semiconductor layer closest to the transparent conductive layer containing zinc oxide However, in a photovoltaic element containing silicon oxide as a main component, heat treatment is performed under high temperature, high humidity, or long-term use, or in a process after forming a transparent conductive layer containing zinc oxide. Even if the process includes a reducing atmosphere such as annealing and hydrogen treatment, the diffusion of zinc atoms into the semiconductor layer containing silicon atoms is suppressed, and the decrease in transmittance of the transparent conductive layer containing zinc oxide is suppressed. It has been found that a decrease in adhesion between the substrate and the transparent conductive layer containing zinc oxide and between the semiconductor layers is suppressed.

With the above configuration, the following operations are provided. By providing a layer containing silicon oxide in a region of the semiconductor layer containing silicon which is in contact with the transparent conductive layer containing zinc oxide, it is possible to suppress the diffusion of zinc into the semiconductor layer containing silicon atoms. .

Zinc oxide has a band gap of about 3.
3 eV, and when zinc has an excess composition with respect to the stoichiometric ratio due to penetration of zinc atoms between lattices, vacancies of oxygen atoms in lattices, etc., excess zinc forms a donor level. By doing so, it functions as a transparent conductive layer that is transparent in the visible region and has appropriate conductivity.

[0015] On the other hand, excess zinc causes diffusion to the adjacent layer. When diffusion of zinc in zinc oxide occurs in the semiconductor layer, which is a main component of the photovoltaic device, during the semiconductor formation process and during long-term use after formation, a network of silicon atoms is formed. There is a concern that the film quality may be degraded due to disturbance, formation of impurity levels in the band gap, or the like.

In a structure in which a transparent conductive layer containing zinc oxide is in contact with a semiconductor layer containing a pin structure containing silicon atoms, factors that diffuse into the semiconductor layer include zinc, oxygen, and phosphorus and boron. Dopants are mentioned, but when comparing these diffusion coefficients in silicon, the diffusion coefficient of zinc is much larger, and zinc in silicon forms a level at a middle position in the band gap of silicon. The diffusion of zinc is a major factor that greatly impairs the function as a semiconductor layer. Here, by providing a layer containing silicon oxide in a region of the semiconductor layer containing silicon and in contact with the transparent conductive layer containing zinc oxide, it is possible to suppress diffusion of zinc to an adjacent layer. Problems can be reduced.

As a specific configuration example, the semiconductor layer containing silicon atoms may be a p-type semiconductor layer, an i-type semiconductor layer, or an n-type semiconductor layer.
Including at least one set of pin junctions made of a type semiconductor layer, between the p-type semiconductor layer or the n-type semiconductor layer closest to the transparent conductive layer containing zinc oxide, and the transparent conductive layer containing zinc oxide. A structure in which a layer containing silicon oxide is provided, wherein the semiconductor layer containing silicon atoms includes at least one set of pin junctions including a p-type semiconductor layer, an i-type semiconductor layer, and an n-type semiconductor layer, and is transparent including the zinc oxide. For example, the p-type semiconductor layer or the n-type semiconductor layer closest to the conductive layer mainly contains silicon oxide.

In the former structure in which a layer containing silicon oxide is provided between the transparent conductive layer containing zinc oxide and the layer containing silicon oxide, the layer containing silicon oxide may be a layer made of only silicon oxide.
It may be a layer containing dopant atoms. When the layer containing silicon oxide is a layer composed of only silicon oxide, the layer is formed to have a thickness that allows carriers generated in the semiconductor layer to be extracted using a tunnel effect.

Specifically, the preferable range is 0.5 nm or more and 5.0 nm or less. It may be deposited on the entire surface,
An island-shaped structure may be used. When a layer containing a dopant atom is used, conductivity with respect to carriers can be ensured as compared with a layer including only silicon oxide.
0.0 nm or less is a preferable range. In the case where the island is formed, the thickness is preferably 30.0 nm or less in the thickest region of the island.

It is considered that the diffusion of zinc progresses more when used under high temperature and high humidity and when used for a long time. In addition, in the case of including a step of a reducing atmosphere such as a heat treatment, an annealing treatment, and a hydrogen treatment in a formation process after zinc oxide, the density of excess zinc atoms in zinc oxide increases. It is effective to suppress the diffusion of zinc.

When moisture is mixed in a long-time use in a high humidity environment or the like, zinc forms a dendritic growth in silicon due to a migration phenomenon, which causes deterioration in characteristics, Furthermore, it is also effective because it causes shunting.

Another effect of the formation of the layer made of silicon oxide is that the adhesion between the transparent conductive layer containing zinc oxide and the semiconductor layer containing silicon atoms is improved. This is because by suppressing the diffusion of zinc in zinc oxide, the crystal structure of zinc oxide is stabilized,
It is considered that the generation of distortion due to the change in internal stress is suppressed. As a result, it is considered that the stress of the lattice of both the semiconductor layer and the transparent conductive layer containing zinc oxide is reduced.

Further, a dopant atom may be introduced into a layer made of silicon oxide, or the p-type semiconductor layer or the n-type semiconductor layer closest to the transparent conductive layer containing zinc oxide may be made mainly of silicon oxide. This makes it possible to form a p-type or n-type semiconductor layer having a wider energy band than a p-type or n-type semiconductor layer made of silicon. When this configuration functions as a BSF (back surface field) structure, there is an effect of suppressing backward diffusion of carriers and improving characteristics of the photovoltaic element.

Further, since the oxygen concentration in the silicon oxide increases toward the transparent conductive layer containing zinc oxide, the above-mentioned effect is particularly exerted on the formation process after the transparent conductive layer containing zinc oxide. This is effective when the process includes a reducing atmosphere, such as a heat treatment, an annealing treatment, and a hydrogen treatment.

Recently, with the aim of developing a low-cost photovoltaic element having high efficiency and stable characteristics over a long period of time, attempts to form a thin semiconductor layer containing a crystal component have been actively made. When a semiconductor layer containing a crystal component is formed by a plasma CVD method, the formation is performed under the condition that the amount of diluted hydrogen is relatively large and the applied high frequency power is large.

Further, in order to form a seed crystal as an underlayer, heat treatment with a halogen lamp heater,
rF laser (oscillation wavelength 193 nm), KrF laser (oscillation wavelength 248 nm), XeCl laser (oscillation wavelength 308 nm), XeF laser (oscillation wavelength 351 nm)
In many cases, the process includes a process under an environment having a stronger reducing action such as an excimer laser annealing process and a hydrogen plasma process. Since these treatments are performed in an environment in which desorption of oxygen from the zinc oxide surface region is more easily promoted, the oxygen concentration in the silicon oxide increases toward the transparent conductive layer containing the zinc oxide. Is particularly effective.

As a method of forming a layer containing silicon oxide, a method of directly forming a layer using a sputtering method or a CVD method, a method of forming a layer made of Si in advance, and then using a thermal oxidation method, an oxygen plasma method, or the like, The method of introducing oxygen into at least a part of the layer made of

As a method of incorporating dopant atoms into a semiconductor layer containing silicon oxide, a method of mixing a gas containing a doping element into a source gas at the time of deposition or an atmosphere gas, or a method of depositing a non-doped gas after depositing without doping. C
VD method, ion implantation method and the like are preferable.

As a method of changing the oxygen concentration in the silicon oxide, a change in the input power, a change in the oxygen flow rate in the source gas, a change in the oxygen partial pressure in the atmosphere gas, and the like are preferable.

Next, the components of the photovoltaic element of the present invention will be described. FIG. 1 is a schematic sectional view showing an example of the photovoltaic element of the present invention. In the figure, 101 is a substrate, 102 is a semiconductor layer, 103 is a second transparent conductive layer, and 104 is a current collecting electrode. 101-1 is a base, 101-2 is a metal layer, and 101-3 is a first transparent conductive layer. These are components of the substrate 101.

(Base) As the base 101-1, a metal,
A plate-like member or a sheet-like member made of resin, glass, ceramics, semiconductor bulk, or the like is preferably used. The surface may have fine irregularities. A structure in which light is incident from the substrate side using a transparent substrate may be employed. Further, by forming the base into a long shape, continuous film formation using a roll-to-roll method can be performed. In particular, flexible materials such as stainless steel and polyimide are used for the substrate 101-.
It is suitable as the material of (1).

(Metal Layer) The metal layer 101-2 has a role as an electrode and a role as a reflection layer that reflects light reaching the base 101-1 and reuses the light in the semiconductor layer 102. The materials include Al, Cu, Ag, Au,
CuMg, AlSi, or the like can be suitably used. As the forming method, methods such as vapor deposition, sputtering, electrodeposition, and printing are suitable. The metal layer 101-2 preferably has irregularities on its surface. Accordingly, the optical path length of the reflected light in the semiconductor layer 102 can be extended, and the short-circuit current can be increased. In the case where the base 101-1 has an exclusive property, the metal layer 101-2 may not be formed.

(First Transparent Conductive Layer) First Transparent Conductive Layer 1
01-3 has a role of increasing the irregular reflection of incident light and reflected light and extending the optical path length in the semiconductor layer 102. Also,
It has a role of preventing the element of the metal layer 101-2 from diffusing or migrating into the semiconductor layer 102 and preventing the photovoltaic element from shunting. Furthermore, by having an appropriate resistance, it has a role of preventing a short circuit due to a defect such as a pinhole in the semiconductor layer.

Further, the first transparent conductive layer 101-3 comprises
Like the metal layer 101-2, it is desirable that the surface has irregularities. The first transparent conductive layer 101-3 is made of Zn
O, preferably made of a conductive oxide such as ITO,
It is preferably formed using a method such as vapor deposition, sputtering, CVD, or electrodeposition. A substance that changes the conductivity may be added to these conductive oxides.

The zinc oxide layer is preferably formed by a method such as sputtering or electrodeposition.

The conditions for forming the zinc oxide film by the sputtering method are greatly affected by the method, the type and flow rate of the gas, the internal pressure, the input power, the film forming speed, the substrate temperature, and the like. For example, D
When a zinc oxide film is formed by a C magnetron sputtering method using a zinc oxide target, the types of gases include Ar, Ne, Kr, Xe, Hg, and O _2. For example, when the volume of the film formation space is 20 liters, 1 s
Ccm to 100 sccm is desirable. The internal pressure during film formation is preferably from 1 × 10 ⁻⁴ Torr to 0.1 Torr. The input power depends on the size of the target, but is preferably from 10 W to 100 KW when the diameter is 15 cm. The preferable range of the substrate temperature varies depending on the film forming speed. However, when forming the film at 1 μm / h, the substrate temperature ranges from 70 ° C. to 450 ° C.
It is desirable that

As for the conditions for forming the zinc oxide film by the electrodeposition method, it is preferable to use an aqueous solution containing nitrate ions and zinc ions in a corrosion-resistant container. The concentration of nitrate ion and zinc ion is from 0.001 mol / l to 1.0 m
ol / l, preferably 0.01 mol / l.
more preferably from 1 to 0.5 mol / l,
More preferably, it is in the range of 0.1 mol / l to 0.25 mol / l.

The source of nitrate ion and zinc ion is not particularly limited, and zinc nitrate, which is a source of both ions, or a water-soluble nitrate such as ammonium nitrate, which is a source of nitrate ion; It may be a mixture of zinc salts such as zinc sulfate, which is a source of zinc ions. Furthermore, it is also preferable to add a carbohydrate to these aqueous solutions in order to suppress abnormal growth and improve adhesion.

The type of carbohydrate is not particularly limited, but monosaccharides such as glucose (glucose) and fructose (fructose), disaccharides such as maltose (maltose) and saccharose (sucrose), dextrin, starch and the like. Polysaccharides and the like or a mixture thereof can be used.

The amount of carbohydrate in the aqueous solution depends on the type of carbohydrate, but generally ranges from 0.001 g / l to 300 g / l.
In the range of 0.005 g / l to 10
More preferably, it is in the range of 0 g / l, and 0.01 g / l.
More preferably, it is in the range of 1 to 60 g / l.

When a zinc oxide film is deposited by an electrodeposition method, it is preferable that the substrate on which the zinc oxide film is deposited in the aqueous solution is used as a cathode and zinc, platinum, carbon or the like is used as an anode. At this time, the current density flowing through the load resistor is 10
It is preferably from mA / dm to 10 A / dm.

(Substrate) The substrate 101-
A substrate 101 is formed by laminating a metal layer 101-2 and a first transparent conductive layer 101-3 on the substrate 1 as needed. Further, an insulating layer may be provided on the substrate 101 in order to facilitate integration of elements.

(Semiconductor Layer) As a main material of the silicon-based semiconductor and the semiconductor layer 102 of the present invention, an amorphous phase or a crystalline phase, or a mixed phase Si thereof is used. Instead of Si, an alloy of Si and C or Ge may be used.

The semiconductor layer 102 contains hydrogen and / or halogen atoms at the same time. The preferred content is 0.1 to 40 atomic%. The semiconductor layer contains a group III element to be a p-type semiconductor layer, and contains a group V element to be an n-type semiconductor layer.

As the electric characteristics of the p-type layer and the n-type layer, those having an activation energy of 0.2 eV or less are preferable.
The one with 0.1 eV or less is optimal.

The specific resistance is preferably 100 Ωcm or less, and most preferably 1 Ωcm or less. In the case of a stack cell (a photovoltaic element having a plurality of pin junctions), it is preferable that the band gap of the i-type semiconductor layer of the pin junction near the light incident side is wide, and the band gap becomes narrower as the pin junction becomes farther. .

Further, it is preferable that the band gap has a minimum value closer to the p layer than the center in the film thickness direction inside the i layer. As the doped layer (p-type layer or n-type layer) on the light incident side, a crystalline semiconductor with little light absorption or a semiconductor with a wide band gap is suitable. As an example of a stack cell in which two sets of pin junctions are stacked, a combination of an i-type silicon-based semiconductor layer, a (amorphous semiconductor layer, a semiconductor layer containing a crystal phase), a (semiconductor layer containing a crystal phase, a crystal Phase-containing semiconductor layer).

Further, as an example of a photovoltaic element in which three sets of pin junctions are stacked, a combination of an i-type silicon-based semiconductor layer and a light incident side (amorphous semiconductor layer, amorphous semiconductor layer, and semiconductor layer containing a crystalline phase) , (A semiconductor layer containing an amorphous or crystalline phase, a semiconductor layer containing a crystalline phase) and (a semiconductor layer containing a crystalline phase, a semiconductor layer containing a crystalline phase, a semiconductor layer containing a crystalline phase).

The i-type semiconductor layer has an absorption coefficient (α) of light (630 nm) of 5000 cm ⁻¹ or more and a photoconductivity (σp) of simulated sunlight irradiation by a solar simulator (AM 1.5, 100 mW / cm ² ). Is 10 × 10 ^-5 S /
cm, the dark conductivity (σd) is preferably 10 × 10 ⁻⁶ S / cm or less, and the Urbach energy by the constant photocurrent method (CPM) is preferably 55 meV or less. A slightly p-type or n-type semiconductor layer can be used as the i-type semiconductor layer.

The semiconductor layer 102 as a component of the present invention will be further described. FIG. 2 shows a semiconductor layer 102 having a set of pin junctions as an example of the semiconductor layer of the present invention.
FIG.

In the figure, 102-1A is a layer containing silicon oxide, 102-1 is an n-type semiconductor layer containing a crystal phase, and furthermore, an i-type semiconductor layer 102-2 containing a crystal phase and containing a crystal phase. p-type semiconductor layer 102-3, layer 102 containing silicon oxide
-3A is laminated.

Here, the layers containing silicon oxide of 102-1A and 102-3A are provided when the adjacent transparent conductive layer contains zinc oxide.

The layers containing silicon oxide of 102-1A and 102-3A are 102-1 and 102-3, respectively.
And may contain a dopant atom having the same conductivity type. Further, as shown in FIG. 3, an n-type semiconductor layer 102-1B including a crystal phase mainly containing silicon oxide, an i-type semiconductor layer 102-2 including a crystal phase mainly, a crystal phase mainly containing silicon oxide And the entirety of the layer exhibiting the conductivity type may be a layer containing silicon oxide as a main component.

Also, a combination of the above patterns may be used. In a semiconductor layer having a plurality of pin junctions, it is preferable that the layer adjacent to the transparent conductive layer containing zinc oxide include a layer containing silicon oxide. Further, the conductivity type on the light incident side may be a p-type semiconductor layer or an n-type semiconductor layer.

(Method for Forming Semiconductor Layer) In order to form the semiconductor layer 102 of the present invention, a high-frequency plasma CVD method is suitable. Hereinafter, a preferred example of a procedure for forming the semiconductor layer 102 by a high-frequency plasma CVD method will be described. (1) The inside of the deposition chamber (vacuum chamber) which can be reduced in pressure is reduced to a predetermined deposition pressure. (2) A material gas such as a source gas or a dilution gas is introduced into the deposition chamber, and the deposition chamber is set to a predetermined deposition pressure while exhausting the deposition chamber by a vacuum pump. (3) The substrate 101 is set to a predetermined temperature by a heater. (4) The high frequency oscillated by the high frequency power supply is introduced into the deposition chamber. The method of introducing into the deposition chamber is as follows: a high frequency is guided by a waveguide and introduced into the deposition chamber through a dielectric window such as alumina ceramics, or a high frequency is guided by a coaxial cable and introduced into the deposition chamber through a metal electrode. There are ways to do that. (5) Plasma is generated in the deposition chamber to decompose the source gas, and a deposited film is formed on the substrate 101 disposed in the deposition chamber. This procedure is repeated a plurality of times as needed to form the semiconductor layer 102.

Silicon-based semiconductor and semiconductor layer 1 described above
02, the substrate temperature in the deposition chamber was 100
~ 450 ° C, pressure 0.5mTorr ~ 100Torr
As r, the high frequency power is preferably 0.001 to 2 W / cm ³ . As a material gas suitable for forming the silicon-based semiconductor and the semiconductor layer 102, Si
Examples include gasizable compounds containing silicon atoms, such as H ₄ , Si ₂ H ₆ , and SiF ₄ . In the case of using an alloy, it is desirable to add a gasizable compound containing Ge and C, such as GeH ₄ or CH ₄ , to the source gas. It is desirable that the source gas be diluted with a dilution gas and introduced into the deposition chamber. Examples of the dilution gas include H ₂ and He. Further, a gasifiable compound containing nitrogen, oxygen or the like may be added as a source gas or a diluent gas. B ₂ H ₆ , BF ₃ or the like is used as a dopant gas for turning the semiconductor layer into a p-type layer. Further, as a dopant gas for converting the semiconductor layer into an n-type layer, P
H ₃ , PF ₃ or the like is used. When depositing a thin film of a crystalline phase or a layer having a small light absorption or a wide band gap such as SiC, increase the ratio of the diluent gas to the source gas,
It is preferable to introduce a relatively high power high frequency.

When the layer containing silicon oxide of the present invention is formed by a sputtering method, the method, the type and the flow rate of the gas, the internal pressure, the input power, the film forming rate, the substrate temperature, and the like have a great influence.
For example, when a film containing silicon oxide is formed using a silicon oxide target by an RF magnetron sputtering method, the types of gas include Ar, Ne, Kr, Xe, Hg, and O _2.
The flow rate varies depending on the size of the apparatus and the pumping speed. For example, when the volume of the film forming space is 20 liters, the flow rate is preferably 1 sccm to 100 sccm.

The internal pressure during film formation is 1 × 10 ⁻⁴ Torr.
To 0.1 Torr is desirable. The input power depends on the size of the target, but is preferably from 10 W to 100 KW when the diameter is 15 cm. The preferable range of the substrate temperature varies depending on the film forming speed, but when forming the film at 1 μm / h, the substrate temperature is preferably from 70 ° C. to 450 ° C.

In the case of forming by a CVD method, a mixed gas of SiH ₄ , O ₂ and an oxygen compound is preferable as a source gas. At this time, since SiH ₄ and O ₂ easily react, they are introduced in different systems. As the formation conditions, the substrate temperature in the deposition chamber is 100 to 450 ° C., and the pressure is 0.5 mTo.
rr-10 Torr, high frequency power 0.001-1 W
/ Cm ³ is a preferable condition.

(Second transparent conductive layer) Second transparent conductive layer 1
Reference numeral 03-1 denotes an electrode on the light incident side, and can also serve as an antireflection film by appropriately setting its film thickness. The second transparent conductive layer 103 is a semiconductor layer 1
02 is required to have a high transmittance in the absorbable wavelength region and a low resistivity. Preferably 5
It is desirable that the transmittance at 50 nm be 80% or more, more preferably 85% or more.

The material of the second transparent conductive layer 103 is as follows.
ITO, ZnO, In ₂ O _{3 and the} like can be suitably used. The formation method includes vapor deposition, CVD, spray,
Methods such as spin-on and dipping are suitable. A substance that changes conductivity may be added to these materials. If the second transparent conductive layer formed by the ZnO is optionally the ratio R _M of the oxygen amount with respect to the amount of zinc in the zinc oxide in the region in contact with the semiconductor layer is zinc oxide in the portion other than the intermediate layer may be provided as necessary an intermediate layer 103-2 formed larger than the ratio R _B of the oxygen amount with respect to the zinc content in the.

(Current Collecting Electrode) The current collecting electrode 104 is provided on the transparent electrode 103 to improve current collecting efficiency. As the forming method, a method of forming a metal of an electrode pattern by sputtering using a mask, a method of printing a conductive paste or a solder paste, a method of fixing a metal wire with a conductive paste, and the like are preferable.

Incidentally, if necessary, protective layers may be formed on both surfaces of the photovoltaic element. At the same time, a teaching material such as a steel plate may be used in combination on the back surface (first incident side and reflection side) of the photovoltaic element.

[0064]

EXAMPLES In the following examples, the present invention will be specifically described by taking a solar cell as an example of a photovoltaic element, but these examples do not limit the content of the present invention at all.

Example 1 A photovoltaic element was formed by the following procedure using the deposited film forming apparatus 201 shown in FIG.
The pin type photovoltaic element shown in FIG. 5 was formed. FIG. 5 is a schematic cross-sectional view showing an example of a photovoltaic device having a silicon-based semiconductor according to the present invention. In the figure, the same members as those in FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted.

The semiconductor layer of this photovoltaic element includes a layer 102-1A containing silicon oxide and an n-type semiconductor layer 10 containing a crystal phase.
2-1; an i-type semiconductor layer 102-2 containing a crystal phase; and a p-type semiconductor layer 102-3 containing a crystal phase. That is, this photovoltaic element is a so-called pin type single cell photovoltaic element.

FIG. 4 is a schematic sectional view showing an example of a deposited film forming apparatus for manufacturing a silicon-based semiconductor and a photovoltaic element according to the present invention.

A deposition film forming apparatus 201 shown in FIG. 4 includes a substrate delivery container 202 and semiconductor forming vacuum containers 211 to 2.
17, the substrate take-up container 203 is configured to be connected via a gas gate. A strip-shaped conductive substrate 204 is set in the deposition film forming apparatus 201 through each container and each gas gate. The strip-shaped conductive substrate 204 is unwound from a bobbin provided in the substrate unloading container 202, and is wound on another bobbin by the substrate unwinding container 203.

The semiconductor forming vacuum vessels 211 to 217
Each has a deposition chamber, and discharge electrodes 2 in the discharge chamber.
Glow discharge is generated by applying high-frequency power from 41 to 247 to high-frequency power supplies 251 to 257, thereby decomposing the source gas and depositing a semiconductor layer on the conductive substrate 204. Also, each semiconductor forming vacuum vessel 211
217 are connected to gas introduction pipes 231 to 237 for introducing a raw material gas and a dilution gas.

The space between the semiconductor forming vacuum container 212 and the semiconductor forming vacuum container 213 and the semiconductor forming vacuum container 21
Crystallization containers 221 and 222 for crystallization means are provided between the semiconductor device 5 and the semiconductor formation vacuum container 216. The crystallization vessels 221 and 222 have gas introduction pipes 227 and 22 respectively.
8. Excimer laser devices 223 and 224 are provided.

Although the deposited film forming apparatus 201 shown in FIG. 4 has seven semiconductor forming vacuum apparatuses, in the following embodiment, it is necessary to generate a glow discharge in all the semiconductor forming vacuum vessels. However, the presence or absence of glow discharge in each container can be selected according to the layer configuration of the photovoltaic element to be manufactured.

Each semiconductor forming apparatus is provided with a film formation region adjusting plate (not shown) for adjusting the contact area between the conductive substrate 204 and the discharge space in each deposition chamber.
By adjusting this, the thickness of each semiconductor film formed in each container can be adjusted.

Next, a bobbin around which the conductive substrate 204 is wound is mounted on the substrate delivery container 202, and the conductive substrate 204 is loaded with the gas gate on the loading side, and the semiconductor forming vacuum containers 211 and 2.
12, crystallization container 221, semiconductor formation container 213, 2
14, 215, crystallization container 222, semiconductor formation container 21
6, 217, through the gas gate on the carry-out side, the substrate was taken up to the substrate winding container 203, and the tension was adjusted so that the belt-shaped conductive substrate 204 did not slack.

Then, the substrate delivery container 202 and the semiconductor formation vacuum containers 211, 212, 213, 214, 21
5, 216, 217, the crystallization containers 221 and 222, and the substrate take-up container 203 were sufficiently evacuated to 5 × 10 ⁻⁶ Torr or less by an evacuation system including a vacuum pump (not shown).

Next, while operating the vacuum evacuation system, the gas introduction pipes 231-2 are introduced into the semiconductor formation vacuum vessels 211-214.
From 34, a raw material gas and a diluent gas were supplied to the crystallization vessel 221 at a hydrogen gas flow of 500 sccm.

Further, vacuum containers 211 to 21 for forming semiconductors
200 sccm H ₂ gas is supplied from a gas introduction pipe to the semiconductor formation vacuum vessel and the crystallization vessel 222 other than 4, and at the same time, 500 sccm H ₂ gas is supplied as a gate gas to each gas gate from each gate gas supply pipe (not shown). did. In this state, the evacuation capacity of the evacuation system was adjusted to adjust the pressure in the semiconductor formation vacuum vessels 211 to 214 to a desired pressure. The forming conditions are as shown in Table 1. At this time, the gas introduction pipe 231 is composed of two independent systems,
₄ and O ₂ were not mixed in the gas inlet tube. The pressure inside the crystallization vessel 221 was maintained at 2 Torr.

[Table 1]

When the pressure in the semiconductor formation vacuum containers 211 to 214 was stabilized, the movement of the conductive substrate 204 in the direction from the substrate delivery container 202 to the substrate take-up container 203 was started.

Next, semiconductor forming vacuum vessels 211 to 21
4, high-frequency power supplies 251-2
A high frequency is introduced from 54 and the semiconductor forming vacuum vessel 211
Glow discharge is generated in the deposition chambers 214 to 214, a layer containing silicon oxide (thickness: 1.5 nm) is formed on the conductive substrate 204, and an amorphous n-type semiconductor layer (thickness: 20 nm), and then crystallized by a XeCl excimer laser (pulse energy 150
mJ / cm ² ) to form an n-type semiconductor layer including a crystal phase, and then forming an i-type semiconductor layer including a crystal phase (thickness: 1.5 μm) on the n-type semiconductor layer including the crystal phase. A p-type semiconductor layer containing a crystalline phase (thickness: 10 nm) was formed to form a photovoltaic element (Example 1-1).

Here, high-frequency power having a frequency of 13.56 MHz and a power density of 5 mW / cm ³ is applied to the vacuum chamber 211 for semiconductor formation, and high-frequency power having a power density of 5 mW / cm ³ is applied to the vacuum chamber 212 for semiconductor formation. High frequency power is supplied to the semiconductor forming vacuum vessel 213 at a frequency of 100.
A high frequency power of 20 MHz and a power density of 20 mW / cm ³ was introduced. 13. The frequency 13.
56 MHz and a power density of 30 mW / cm ³ were introduced.

Next, using a continuous modularization apparatus (not shown), the formed band-like photovoltaic element was
m solar cell module (Example 1-2).
Next, a photovoltaic element (Comparative Example 1-1) was produced in the same manner as in Example 1-1, except that the layer containing silicon oxide was not formed by the deposited film forming apparatus 211. A solar cell module was formed in the same manner as in (Comparative Example 1-2).

The photovoltaic elements of Example 1-1 and Comparative Example 1-1 were placed between the conductive substrate and the semiconductor layer using the cross-cut tape method (interval of cuts of 1 mm, number of squares of 100). The adhesion was examined. Further, the solar cell modules of Example 1-2 and Comparative Example 1-2, whose initial photoelectric conversion efficiencies were measured in advance, were set in a dark place at a temperature of 85 ° C. and a humidity of 85%.
Hold for 30 minutes, then lower to -20 ° C over 70 minutes 30
The temperature was kept at 85 ° C. and the humidity was returned to 85% over 70 minutes. This cycle was repeated 100 times. Then, the photoelectric conversion efficiency was measured again, and the change in the photoelectric conversion efficiency by the temperature / humidity test was examined. Further, the solar cell modules of Example 1-2 and Comparative Example 1-2 whose initial photoelectric conversion efficiencies were measured in advance were installed in a dark place at a temperature of 85 ° C. and a humidity of 85%, and at the same time, a reverse bias of 10 V was applied. After 500 hours, the photoelectric conversion efficiency was measured again, and a change in the photoelectric conversion efficiency due to application of a reverse bias under high temperature and high humidity was examined. Table 2 shows the results.

[Table 2]

As shown in Table 2, Example 1-1 of the present invention
Example 1-2 including the photovoltaic element of Example 1 and the photovoltaic element
The solar cell module is a photovoltaic element of Comparative Example 1-1,
Compared with the solar cell module of Comparative Example 1-2, adhesion,
Excellent in initial conversion efficiency, durability against temperature / humidity test and high temperature / humidity reverse bias application test. From the above, it can be seen that the solar cell module including the photovoltaic element of the present invention has excellent features.

(Example 2) Using the deposited film forming apparatus 201 shown in FIG. 4, the pin type photovoltaic element shown in FIG. 6 was formed in the following procedure. FIG. 6 is a schematic cross-sectional view schematically illustrating an example of a photovoltaic device having a silicon-based thin film of the present invention. In the figure, the same members as those in FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted. The semiconductor layer of this photovoltaic element is an n-type semiconductor layer 102-1B containing a crystal phase containing silicon oxide as a main component.
And an i-type semiconductor layer 102-2 containing a crystal phase and a p-type semiconductor layer 102-3 containing a crystal phase. That is,
This photovoltaic element is a so-called pin type single cell photovoltaic element.

As in the first embodiment, the belt-shaped conductive substrate 20
4 is mounted on the deposition film forming apparatus 201, and the substrate sending container 202, the semiconductor forming vacuum containers 211 and 21 are prepared.
2, 213, 214, 215, 216, 217, the crystallization containers 221 and 222, and the substrate take-up container 203 were evacuated to 5 × 10 ⁻⁶ T by a vacuum exhaust system including a vacuum pump (not shown).
The vacuum was exhausted sufficiently to orr or lower.

Next, while operating the vacuum evacuation system, the gas introduction pipes 232-2 are introduced into the semiconductor formation vacuum vessels 212-214.
The raw material gas and the dilution gas were supplied from 34.

Further, the semiconductor forming vacuum vessels 212 to 21
For the semiconductor formation vacuum vessels other than 4
0 sccm of H ₂ gas is supplied, and at the same time, 5 g of gate gas is supplied from each gate gas supply pipe (not shown) to each gas gate.
00 sccm of H ₂ gas was supplied. In this state, the evacuation capacity of the evacuation system is adjusted so that the semiconductor forming vacuum vessel 21 is formed.
The pressure within 2-214 was adjusted to the desired pressure. The forming conditions are as shown in Table 3.

[Table 3]

When the pressure in the semiconductor formation vacuum containers 212 to 214 was stabilized, the movement of the conductive substrate 204 in the direction from the substrate delivery container 202 to the substrate take-up container 203 was started.

Next, vacuum containers 212 to 21 for forming semiconductors
4, high-frequency power sources 252 to 244
To 254, a high frequency is introduced, and the semiconductor forming vacuum vessel 2
A glow discharge is generated in the deposition chambers 12 to 214 to form an amorphous n-type semiconductor layer containing silicon oxide as a main component on the conductive substrate 204 (thickness: 30 nm).
Is formed, a crystallization treatment (pulse energy 150 mJ / cm ² ) is performed with a XeCl excimer laser to form an n-type semiconductor layer containing a crystal phase containing silicon oxide as a main component. An i-type semiconductor layer containing a crystalline phase (thickness: 1.5 μm) and a p-type semiconductor layer containing a crystalline phase (thickness: 10 n) are formed on an n-type semiconductor layer containing a crystalline phase.
m) to form a photovoltaic element (Example 2-
1).

Here, high-frequency power having a frequency of 13.56 MHz and a power density of 5 mW / cm ³ is applied to the semiconductor forming vacuum vessel 212, and a frequency of 2.45 GHz and a power density of 50 mW / cm ³ are applied to the semiconductor forming vacuum vessel 213. A high frequency power is applied to the semiconductor forming vacuum vessel 214 at a frequency of 13.5.
A high frequency power of 6 MHz and a power density of 30 mW / cm ³ was introduced.

Next, using a continuous modularization device (not shown), the formed band-shaped photovoltaic element was 36 cm × 22 cm.
(Example 2-2)

Next, a photovoltaic element (Comparative Example 2-1) was produced in the same manner as in Example 2-1 except that hydrogen was introduced instead of oxygen into the deposited film forming apparatus 212. A solar cell module was formed in the same manner (Comparative Example 2-
2).

The photovoltaic elements of Example 2-1 and Comparative Example 2-1 were cut between the conductive substrate and the semiconductor layer by using a cross-cut tape method (interval of cut gap 1 mm, number of squares 100). The adhesion was examined. Further, the solar cell modules of Example 2-2 and Comparative Example 2-2 whose initial photoelectric conversion efficiencies were measured in advance were placed in a dark place at a temperature of 85 ° C. and a humidity of 85%.
Hold for 30 minutes, then lower to -20 ° C over 70 minutes 30
The temperature was kept at 85 ° C. and the humidity was returned to 85% over 70 minutes. This cycle was repeated 100 times. Then, the photoelectric conversion efficiency was measured again, and the change in the photoelectric conversion efficiency by the temperature / humidity test was examined. In addition, the solar cell modules of Example 2-2 and Comparative Example 2-2 whose initial photoelectric conversion efficiencies were measured in advance were installed in a dark place at a temperature of 85 ° C. and a humidity of 85%, and at the same time, a reverse bias of 10 V was applied. After 500 hours, the photoelectric conversion efficiency was measured again, and a change in the photoelectric conversion efficiency due to application of a reverse bias under high temperature and high humidity was examined. Table 4 shows the results.

[Table 4]

As shown in Table 4, Example 2-1 of the present invention
Example 2-2 including the photovoltaic element of Example 1 and the photovoltaic element
The solar cell module is a photovoltaic element of Comparative Example 2-1;
Compared with the solar cell module of Comparative Example 2-2,
Excellent in initial conversion efficiency, durability against temperature / humidity test and high temperature / humidity reverse bias application test. From the above, it can be seen that the solar cell module including the photovoltaic element of the present invention has excellent features.

(Example 3) The photovoltaic element shown in FIG. 7 was formed by the following procedure using the deposited film forming apparatus 201 shown in FIG. FIG. 7 is a schematic cross-sectional view schematically illustrating an example of a photovoltaic device having a silicon-based semiconductor according to the present invention.

In the figure, the same members as those in FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted. The semiconductor layer of this photovoltaic element is
A layer 102-1A containing silicon oxide, an n-type semiconductor layer 102-1 containing a crystal phase, and an i-type semiconductor layer 102-1 containing a crystal phase
2, a p-type semiconductor layer 102-3 containing a crystal phase, an n-type semiconductor layer 102-1 containing a crystal phase, an i-type semiconductor layer 102-5 containing a crystal phase, and a p-type semiconductor layer 102-6 containing a crystal phase ,
It consists of That is, this photovoltaic element is a so-called pinpin type double cell photovoltaic element.

As in the first embodiment, the belt-shaped conductive substrate 20
4 is mounted on the deposition film forming apparatus 201, and the substrate delivery container 202 and the semiconductor formation vacuum containers 211, 212, 21
3, 214, 215, 216, 217, crystallization vessel 22
1, 222, the substrate take-up container 203 was sufficiently evacuated to 5 × 10 ⁻⁶ Torr or less by a vacuum evacuation system including a vacuum pump (not shown).

Next, while operating the vacuum evacuation system, the gas introduction pipes 231-2 are introduced into the semiconductor formation vacuum vessels 211-217.
37, the raw material gas and the dilution gas are supplied to the crystallization vessel 221,
A hydrogen gas of 500 sccm was supplied to 222.

Further, from each gate gas supply pipe (not shown),
500 sccm of H _{2 is used} as a gate gas for each gas gate.
Gas was supplied. In this state, the evacuation capacity of the evacuation system was adjusted to adjust the pressure in the semiconductor formation vacuum vessels 211 to 217 to a desired pressure. The forming conditions were as shown in Table 5. The inside of the crystallization vessels 221 and 222 is 2 To.
The pressure was maintained at rr.

[Table 5]

When the pressure in the semiconductor forming vacuum vessels 211 to 217 was stabilized, the movement of the conductive substrate 204 in the direction from the substrate delivery vessel 202 to the substrate take-up vessel 203 was started.

Next, semiconductor forming vacuum vessels 211 to 21
7, high-frequency power supplies 251-2
High frequency is introduced from 57 and the semiconductor forming vacuum vessel 211
Glow discharge is generated in the deposition chambers 217 to 217, a layer containing silicon oxide (1.5 nm in thickness) is formed on the conductive substrate 204 on the conductive substrate 204, and an amorphous n-type semiconductor layer (film thickness) is formed. 30 nm), and then crystallized by a XeCl excimer laser (pulse energy 150
mJ / cm ² ) to form an n-type semiconductor layer containing a crystal phase, and then form an i-type semiconductor layer containing a crystal phase (2.0 μm in thickness) on the n-type semiconductor layer containing the crystal phase. A bottom cell is formed by forming a p-type semiconductor layer containing a crystalline phase (thickness: 10 nm), and further forming an amorphous n-type semiconductor layer (thickness: 3 nm).
0 nm), and then crystallized by a XeCl excimer laser (pulse energy 150 mJ / cm).
² ) to form an n-type semiconductor layer including a crystal phase, and then forming an i-type semiconductor layer including the crystal phase on the n-type semiconductor layer including the crystal phase.
A top cell was formed by forming a p-type semiconductor layer (thickness: 10 μm) including a crystalline semiconductor layer (thickness: 1.2 μm) and a crystalline phase, thereby forming a double-cell photovoltaic element.

[0102] Here, the frequency 13.56MHz the semiconductor forming vacuum chamber 211, the RF power density 5 mW / cm ^3, frequency 13.56MHz the semiconductor formation vacuum vessel 212, the power density 5 mW / cm ³ High frequency power is supplied to the semiconductor forming vacuum vessel 213 at a frequency of 2.4.
A high frequency power of 5 GHz and a power density of 50 mW / cm ³ is applied to the semiconductor forming vacuum vessel 214 at a frequency of 13.56.
MHz, power density of 30 mW / cm ³
A frequency of 13.56 MH is stored in the semiconductor forming vacuum vessel 215.
z, a high-frequency power with a power density of 5 mW / cm ^3, a high-frequency power with a frequency of 2.45 GHz and a power density of 50 mW / cm ³ for the vacuum vessel 216 for semiconductor formation, a frequency of 13.56 MHz for the vacuum vessel 217 for semiconductor formation, High frequency power with a power density of 30 mW / cm ³ was introduced.

Next, using a continuous modularization apparatus (not shown), the formed band-shaped photovoltaic element was 36 cm × 22 cm.
(Example 3).

The solar cell module of Example 3 shows 1.3 times the photoelectric conversion efficiency as compared with the solar cell module of Example 1-2, and the solar cell module of Example 3 has better adhesion, It has excellent conversion efficiency and durability against temperature and humidity tests and high temperature and high humidity reverse bias application tests. From the above, it can be seen that the solar cell module including the photovoltaic element of the present invention has excellent features.

(Example 4) The photovoltaic element shown in FIG. 9 was formed by the following procedure using the deposited film forming apparatus 201 shown in FIG. FIG. 9 is a schematic cross-sectional view schematically illustrating an example of a photovoltaic device having a silicon-based semiconductor according to the present invention. In the figure, the same members as those in FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted. The semiconductor layer of this photovoltaic element includes an n-type semiconductor layer 102-1B including a crystal phase mainly composed of silicon oxide, an i-type semiconductor layer 102-2 including a crystal phase, and a p-type semiconductor layer 102− including a crystal phase. 3. n-type semiconductor layer 102-1 containing crystal phase
And an i-type semiconductor layer 102-5 containing a crystalline phase and a p-type semiconductor layer 102-6 containing a crystalline phase. That is, this pre-electromotive element is a so-called pinpin type double-cell photovoltaic element.

As in the first embodiment, the belt-shaped conductive substrate 20
4 is mounted on the deposition film forming apparatus 201, and the substrate delivery container 202 and the semiconductor formation vacuum containers 211, 212, 21
3, 214, 215, 216, 217, crystallization vessel 22
1, 222, the substrate take-up container 203 was sufficiently evacuated to 5 × 10 ⁻⁶ Torr or less by a vacuum evacuation system including a vacuum pump (not shown).

Next, while operating the vacuum evacuation system, the gas introduction pipes 231-2 are introduced into the semiconductor formation vacuum vessels 211-217.
37, the raw material gas and the dilution gas are supplied to the crystallization vessel 221,
A hydrogen gas of 500 sccm was supplied to 222.

Further, from each gate gas supply pipe (not shown),
500 sccm of H2 is used as a gate gas for each gas gate.
Gas was supplied. In this state, the evacuation capacity of the evacuation system was adjusted to adjust the pressure in the semiconductor formation vacuum vessels 211 to 217 to a desired pressure. The forming conditions were as shown in Table 6. The inside of the crystallization vessels 221 and 222 is 2 To.
The pressure was maintained at rr.

[Table 6]

When the pressure in the semiconductor formation vacuum containers 211 to 217 was stabilized, the movement of the conductive substrate 204 in the direction from the substrate delivery container 202 to the substrate take-up container 203 was started.

Next, semiconductor forming vacuum vessels 211 to 21
7, high-frequency power supplies 251-2
High frequency is introduced from 57 and the semiconductor forming vacuum vessel 211
Glow discharge is generated in the deposition chamber of the semiconductor substrate 217, an amorphous n-type semiconductor layer (film thickness: 15 nm) mainly composed of silicon oxide is formed on the conductive substrate 204, and the amount of oxygen is reduced. After forming an amorphous n-type semiconductor layer (film thickness: 15 nm) containing silicon oxide as a main component, a heat treatment is performed by an infrared lamp heater 229 to form an n-type semiconductor layer containing a crystal phase containing silicon oxide as a main component. After that, an i-type semiconductor layer containing a crystalline phase (thickness 2.0 μm) and a p-type semiconductor layer containing a crystalline phase (thickness 10 nm) are formed to form a bottom cell. 3
0 nm) and then an infrared lamp heater 230
To form an n-type semiconductor layer including a crystal phase, and then forming an i-type semiconductor layer including a crystal phase (thickness: 1.2 μm) on the n-type semiconductor layer including the crystal phase. A top cell was formed by forming a p-type semiconductor layer (thickness: 10 nm) containing the same, thereby forming a double-cell photovoltaic element.

[0110] Here, the frequency 13.56MHz the semiconductor forming vacuum chamber 211, the RF power density 5 mW / cm ^3, frequency 13.56MHz the semiconductor formation vacuum vessel 212, the power density 5 mW / cm ³ High frequency power is supplied to the semiconductor forming vacuum vessel 213 at a frequency of 2.4.
A high frequency power of 5 GHz and a power density of 50 mW / cm ³ is applied to the semiconductor forming vacuum vessel 214 at a frequency of 13.56.
MHz, power density of 30 mW / cm ³
A frequency of 13.56 MH is stored in the semiconductor forming vacuum vessel 215.
z, a high-frequency power with a power density of 5 mW / cm ^3, a high-frequency power with a frequency of 2.45 GHz and a power density of 50 mW / cm ³ for the vacuum vessel 216 for semiconductor formation, a frequency of 13.56 MHz for the vacuum vessel 217 for semiconductor formation, High frequency power with a power density of 30 mW / cm ³ was introduced.

Next, using a continuous module device (not shown), the formed band-like photovoltaic element was placed in a size of 36 cm × 22 cm.
(Example 4).

The solar cell module of the fourth embodiment is similar to that of the first embodiment.
-2 shows a photoelectric conversion efficiency 1.4 times higher than that of the solar cell module of Example-2, and the solar cell module of Example 4 has adhesion, initial conversion efficiency, durability against a temperature / humidity test and a high temperature / humidity reverse bias application test. Was excellent. From the above, it can be seen that the solar cell module including the photovoltaic element of the present invention has excellent features.

[0113]

As described above, according to the present invention, heat treatment, high temperature, high humidity, or long-term use, or a process after forming a transparent conductive layer containing zinc oxide, Annealing treatment, even in the case of including a process of a reducing atmosphere such as hydrogen treatment, suppresses the diffusion of zinc atoms into the semiconductor layer containing silicon atoms, suppresses the decrease in transmittance of the transparent conductive layer containing zinc oxide, It is possible to suppress a decrease in adhesion between the substrate and the transparent conductive layer containing zinc oxide and between the semiconductor layers.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view illustrating an example of a photovoltaic device according to an embodiment.

FIG. 2 is a schematic cross-sectional view illustrating an example of a semiconductor layer according to an example.

FIG. 3 is a schematic cross-sectional view illustrating an example of a semiconductor layer according to an example.

FIG. 4 is a schematic cross-sectional view showing one example of a deposited film forming apparatus for manufacturing a photovoltaic element according to an embodiment.

FIG. 5 is a schematic cross-sectional view illustrating an example of a photovoltaic device according to an example.

FIG. 6 is a schematic cross-sectional view illustrating an example of a photovoltaic device according to an example.

FIG. 7 is a schematic cross-sectional view illustrating an example of a photovoltaic device according to an example.

FIG. 8 is a schematic cross-sectional view showing one example of a deposited film forming apparatus for manufacturing a photovoltaic element according to an embodiment.

FIG. 9 is a schematic cross-sectional view illustrating an example of a photovoltaic device according to an example.

[Explanation of symbols]

101: Substrate 101-1: Base 101-2: Metal Layer 101-3: First Transparent Conductive Layer 102: Semiconductor Layer 102-1: N-Type Semiconductor Layer Including Crystal Phase 102-1A: Layer Containing Silicon Oxide 102 -1B: n-type semiconductor layer containing a crystal phase containing silicon oxide as a main component 102-2: i-type semiconductor layer containing a crystal phase 102-3: p-type semiconductor layer containing a crystal phase 102-3A: layer containing silicon oxide 102-3B: p-type semiconductor layer including a crystal phase containing silicon oxide as a main component 102-4: n-type semiconductor layer including a crystal phase 102-5: i-type semiconductor layer including a crystal phase 102-6: including a crystal phase p-type semiconductor layer 103: second transparent conductive layer 104: current collecting electrode 201: deposited film forming apparatus 202: substrate sending container 203: substrate winding container 204: conductive substrate 211 to 217: semiconductor forming vacuum container 221 , 222: crystallization vessels 223, 224: excimer laser devices 227, 228, 231-237: gas inlet tubes 229, 230: infrared lamp heaters 241-247: discharge electrodes 251-257: high frequency power supply

Claims (9)

[Claims] 1. A photovoltaic device comprising at least a first transparent conductive layer, a semiconductor layer containing silicon atoms, and a second transparent conductive layer on a substrate, wherein the first transparent conductive layer comprises: At least one layer with the second transparent conductive layer contains zinc oxide, and a layer containing silicon oxide is provided in a region of the semiconductor layer containing silicon atoms in contact with the transparent conductive layer containing zinc oxide. A photovoltaic element characterized by the above-mentioned. 2. The semiconductor layer containing silicon atoms, wherein p
Composed of a p-type semiconductor layer, an i-type semiconductor layer and an n-type semiconductor layer
Including at least one set of in-junction and including silicon oxide between the p-type semiconductor layer or the n-type semiconductor layer closest to the transparent conductive layer containing zinc oxide and the transparent conductive layer containing zinc oxide The photovoltaic device according to claim 1, further comprising a layer. 3. The photovoltaic device according to claim 2, wherein the layer containing silicon oxide contains a dopant atom. 4. The semiconductor layer containing silicon atoms, wherein p
Composed of a p-type semiconductor layer, an i-type semiconductor layer, and an n-type semiconductor layer
The p-type semiconductor layer closest to the transparent conductive layer containing the zinc oxide, which includes at least one set of n junctions or the n-type junction.
The photovoltaic device according to claim 1, wherein the type semiconductor layer contains silicon oxide as a main component. 5. The photovoltaic device according to claim 1, wherein the oxygen concentration in the silicon oxide increases toward the transparent conductive layer containing the zinc oxide. 6. The photovoltaic device according to claim 1, wherein a crystallization process is performed in at least a part of a process of forming the semiconductor layer containing silicon atoms. 7. The photovoltaic device according to claim 6, wherein the crystallization treatment is at least one of a heating treatment, an annealing treatment, and a hydrogen treatment. 8. The semiconductor device according to claim 1, wherein said semiconductor layer is formed by a plasma CVD method using a high frequency.
8. The photovoltaic device according to any one of items 7 to 7. 9. The photovoltaic device according to claim 1, wherein the semiconductor layer includes a crystal phase.