JP2004273886A - Crystalline thin film semiconductor device and photovoltaic device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a large-area crystalline thin film semiconductor device, such as the solar cell etc., that can achieve conversion efficiency of >10%. <P>SOLUTION: The crystalline thin film semiconductor device is constituted by forming a conductive electrode layer 02 on the partial or whole surface of a substrate 1, a barrier layer 3 on the electrode layer 2 to restrict the diffusion of the substance constituting the electrode layer 2, and a non-single-crystal layer 4 on the barrier layer 3. The non-single-crystal layer 4 is changed to a crystalline layer by annealing the layer 4 with a laser beam or lamp or the semiconductor layer 4a is formed in a crystalline layer. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a semiconductor element substrate, a crystalline thin film semiconductor device such as a semiconductor element, and a photovoltaic device.
[0002]
[Prior art]
In recent years, research on forming a silicon crystal thin film on a nonconductive different kind of substrate, such as a glass substrate, has been actively conducted. The silicon crystal thin film formed on this glass substrate has a wide range of applications, and can be used for TFTs for liquid crystal devices, thin film photoelectric conversion elements, and the like.
[0003]
The thin film photovoltaic power generation device is a device in which a crystalline silicon thin film having good crystallinity is formed on an inexpensive substrate by a low-temperature process, and this is used for a photoelectric conversion device to achieve low cost and high performance. By using this crystalline silicon thin film for the photoelectric conversion element, light degradation, which is a problem in the amorphous silicon photoelectric conversion element, is not observed. It can be converted to electrical energy. This technology is expected to be applicable not only to photoelectric conversion elements but also to photoelectric conversion devices such as optical sensors.
[0004]
This silicon crystal photoelectric conversion element generally uses a technique of directly depositing a crystalline silicon thin film by plasma CVD. It is known that crystalline silicon can be formed on a substrate at a low temperature by this method, and is said to be effective in reducing costs.
[0005]
In this method, the plasma CVD formation conditions are as follows: the silane-based source gas is diluted about 15 times or more with hydrogen, the pressure in the plasma reaction chamber is 10 mTorr-10 Torr, and the substrate temperature is 150 ° C. to 550 ° C., preferably 400 ° C. or less. The film is controlled within the range described above. As a result, a crystalline silicon thin film is formed on the substrate. However, it has been difficult to form polysilicon having a large crystal grain size by this method. In addition, the quality of the i-layer, which plays a fundamental role in the power generation function, is sharply reduced when doping is performed to optimize the element structure. For these reasons, it has been difficult to achieve an efficiency greatly exceeding 10% with a single cell advantageous for cost reduction.
[0006]
On the other hand, various attempts to crystallize by scanning with a laser have been studied, and a method using a continuous wave has already been disclosed in the official gazette (for example, see Patent Document 1). This method forms amorphous silicon on a heterogeneous substrate and melts and crystallizes it into a polycrystalline silicon layer by scanning with a continuous wave light source in the form of a strip.It is possible to grow long crystal grains in the scanning direction. And
[0007]
[Patent Document 1]
Japanese Patent Application Laid-Open No. 2001-351863 (paragraph numbers 0024 and 0030; FIGS. 1 and 2)
[0008]
[Problems to be solved by the invention]
However, when a highly efficient solar cell is to be formed, the above-described method of crystallizing by scanning with a continuous wave laser has the following problems.
[0009]
That is, this method of crystallizing by scanning with a laser has been devised for the purpose of a TFT (Thin Film Transistor). In other words, it is a lateral device, and there is no need to form electrodes above and below the crystalline silicon film. On the other hand, a vertical device such as a solar cell needs to form electrodes on the upper and lower sides.
[0010]
However, when amorphous silicon is formed on an electrode and then crystallized, an electrode material such as Al diffuses instantaneously into silicon, which significantly degrades device characteristics. Further, even when a high melting point material is used, the diffusion due to the heat of fusion cannot be escaped, adversely affecting the characteristics. This was fatal in making solar cells over 10%.
[0011]
For the above reasons, the conventional techniques have been insufficient to form a highly efficient solar cell.
[0012]
The present invention has been made in view of the above problems, and provides a means for easily manufacturing a large-area crystalline thin-film semiconductor device such as a solar cell capable of achieving a conversion efficiency exceeding 10%.
[0013]
[Means for Solving the Problems]
In order to achieve the above object, the present invention is configured as follows.
[0014]
According to a first aspect of the present invention, there is provided a crystalline thin film semiconductor device in which a conductive electrode layer is formed on a part or the whole of a substrate, and is formed for the purpose of limiting diffusion of a material constituting the electrode layer on the electrode layer. Is formed, a non-single-crystal layer is formed thereon, and the non-single-crystal layer is annealed by a laser or a lamp, so that the non-single-crystal layer is changed into a crystalline state or the crystalline state is changed. It is characterized by having a changed semiconductor layer.
[0015]
In other words, a conductive electrode layer (backside electrode layer) is formed on a part or all of the substrate, and a barrier layer formed on the substrate to restrict diffusion of a material constituting the electrode layer. Is formed, and a semiconductor layer is formed thereon, and the semiconductor layer is changed to crystalline by annealing a non-single-crystal layer formed on the barrier layer by a laser or a lamp. Or a layer whose crystallinity has been changed.
[0016]
According to a second aspect of the present invention, in the crystalline thin film semiconductor device according to the first aspect, the non-single-crystal layer of the semiconductor layer is annealed by a laser or a lamp having a continuous output.
[0017]
According to a third aspect of the present invention, in the crystalline thin film semiconductor device according to the first or second aspect, the semiconductor layer is in electrical contact with the electrode layer (backside electrode layer).
[0018]
According to a fourth aspect of the present invention, in the crystalline thin film semiconductor device according to any one of the first to third aspects, all or a part of the electrode layer is made of Al or a compound thereof.
[0019]
According to a fifth aspect of the present invention, in the crystalline thin film semiconductor device according to any one of the first to fourth aspects, the semiconductor layer is polycrystalline.
[0020]
According to a sixth aspect of the present invention, in the crystalline thin film semiconductor device according to the fifth aspect, the semiconductor layer has a radius from a certain point on the surface of the semiconductor layer which is equal to or larger than the film thickness when viewed from above the substrate. Is characterized in that there is a place where no grain boundary exists, and there is no grain boundary crossing the cross-sectional direction at that point.
[0021]
According to a seventh aspect of the present invention, in the crystalline thin film semiconductor device according to the fifth aspect, in the polycrystalline semiconductor layer, 80% or more of the crystal grain boundaries are parallel to or parallel to the direction in which the laser or lamp is scanned. Characterized by a direction within 45 degrees with respect to.
[0022]
According to an eighth aspect of the present invention, in the crystalline thin film semiconductor device according to any one of the first to seventh aspects, a single crystal or a non-crystal having a conductivity type different from that of the semiconductor layer is provided on all or at least a part of the upper part of the semiconductor layer. It is characterized in that a single-crystal second semiconductor layer is formed.
[0023]
According to a ninth aspect of the present invention, in the crystal thin film semiconductor device according to the eighth aspect, a conductive antireflection layer that is transparent to visible light is formed on the second semiconductor layer. An electrode (extraction electrode) is formed on a part of the upper part of the prevention layer.
[0024]
According to a tenth aspect of the present invention, in the crystalline thin film semiconductor device according to any one of the first to ninth aspects, the electrode layer (backside electrode layer) is formed of Al, Ag, Sb, Ni, Mo, Ti, Pt, Co, Zn. , Cu, Au, Fe or W, or a compound containing these elements.
[0025]
According to an eleventh aspect of the present invention, in the crystalline thin film semiconductor device according to any one of the first to tenth aspects, the barrier layer is mainly composed of silicon oxide, silicon nitride, silicon oxynitride, ITO, zinc oxide, and tin oxide. Characterized by comprising any of the following substances:
[0026]
According to a twelfth aspect of the present invention, there is provided a photovoltaic device comprising the crystalline thin film semiconductor device according to any one of the first to eleventh aspects.
[0027]
<The gist of the invention>
In the crystalline thin film semiconductor device of the present invention, a conductive electrode layer is formed on a part or the whole of a substrate, and a barrier layer formed on the upper part thereof for the purpose of restricting diffusion of a material constituting the electrode layer. Is formed, and a semiconductor layer is formed thereon, and the semiconductor layer is changed to crystalline by annealing a non-single-crystal layer formed on the barrier layer by a laser or a lamp. Layer or a layer whose crystallinity is changed.
[0028]
According to the present invention, when light energy is applied to a non-single-crystal layer to form a crystallized or crystallized semiconductor layer (for example, a crystalline silicon film), energy is also applied to the electrode layer. As a result, the elements constituting the electrode layer pass through the barrier layer and slightly leak to the back side of the crystalline silicon film, and the electrode layer and the crystalline silicon layer are electrically connected. Therefore, by using the crystalline silicon thin film forming the lower electrode in this manner, a high-quality semiconductor device such as a solar cell can be formed as a vertical device.
[0029]
The degree to which the above-mentioned element constituting the electrode layer penetrates the barrier layer and enters the non-single-crystal layer, that is, the concentration, is controlled by the material and thickness of the barrier layer. Therefore, it is possible to perform diffusion only in the vicinity of the back surface electrode of the crystalline silicon layer without distributing it at a high concentration throughout the crystalline silicon layer. Further, the electrode material diffused in the crystalline silicon layer can be used as a p-type dopant. Since this feature can be applied to a BSF (Back Surface Field) of a solar cell, it is very effective for manufacturing a highly efficient polysilicon thin film solar cell.
[0030]
The semiconductor layer, when viewed from the top of the substrate, has a portion where no crystal grain boundary exists in a region whose radius is equal to or larger than a certain point on the surface of the semiconductor layer, and a cross section at that point. An area satisfying the condition that there is no crystal grain boundary crossing the direction can be used as a high-quality thin-film semiconductor device having a lower electrode.
[0031]
Further, in order to construct this device as a solar cell and construct a photovoltaic device, a semiconductor layer (second semiconductor layer) of a reverse conductivity type may be formed on the above-mentioned semiconductor layer. A desired pn junction is formed between the first semiconductor layer and the second semiconductor layer of the opposite conductivity type.
[0032]
BEST MODE FOR CARRYING OUT THE INVENTION
The crystalline thin film semiconductor device of the present invention has a basic configuration as shown in FIGS. First, a layer (hereinafter referred to as a barrier layer) 3 made of a material having a composition different from that of crystalline silicon or amorphous silicon is formed on the substrate 1 on which the electrode layer (backside electrode layer) 2 is formed. A non-single-crystal silicon layer (non-single-crystal layer) such as the amorphous silicon layer 4 is formed thereon, energy is given by continuous light, and the non-single-crystal silicon is crystallized by melting and cooling. And a crystalline silicon film (semiconductor layer) 4a. During this crystallization, the elements constituting the electrode layer 2 pass through the barrier layer 3 and slightly leak to the back side of the crystalline silicon film 4a, so that the electrode layer 2 and the crystalline silicon layer 4a are electrically connected. It becomes. Using the crystalline silicon thin film constituting the lower electrode in this way, a high-quality semiconductor device such as a vertical device such as a solar cell can be formed.
[0033]
First, a conductive or non-conductive substrate 1 is prepared. The electrode layer 2 is formed on this substrate. As an example, as the electrode material, an electrode mainly composed of an Al electrode is suitable, but in addition, a metal electrode having conductivity, a transparent conductive oxide film of SnO ₂ , ITO, or the like, or another electrode having conductivity. Any layer can be used. Thereafter, a barrier layer 3 is formed on the electrode layer. The barrier layer 3 can be made of, for example, silicon oxide or silicon nitride.
[0034]
On this, a non-single-crystal layer, for example, an amorphous silicon layer 4 is formed. When this device is used for a solar cell, the active layer is deposited as necessary for the thickness of the active layer.
[0035]
Thereafter, the active layer is formed by melting and crystallizing (recrystallizing) using a laser or a lamp. At this time, if doping needs to be performed in the film, doping is performed in advance in the amorphous silicon layer 4. However, if necessary, doping by ion implantation may be performed after crystallization.
[0036]
As a heat source used for this crystallization, a laser or a lamp can be used, but it is desirable to use a laser in order to form a lower-cost device. Various types of lasers can be used for this laser. One example is the second harmonic (532 nm) of a YAG laser (Nd: YAG). A YAG laser is easy to handle, unlike a gas laser such as an excimer laser. Further, since continuous oscillation is possible, polysilicon having a large grain size can be formed.
[0037]
At the time of this crystallization, very large energy is given to the amorphous silicon layer 4. The energy also applies energy to the electrode layer 2 below the barrier layer 3. Due to this energy, the element constituting the electrode layer breaks through the barrier layer 3 and penetrates into the amorphous silicon layer 4. However, since the concentration is controlled by the material and the thickness of the barrier layer 3, the diffusion can be performed only in the vicinity of the back surface of the crystalline silicon layer 4a without being distributed at a high concentration throughout the crystalline silicon layer 4a. It is. Further, by using an element serving as a dopant in the crystalline silicon, for example, Al, the electrode material diffused in the crystalline silicon layer 4a can be used as a p-type dopant. Since this feature can be applied to a solar cell BSF ((Back Surface Field)), it is very effective for manufacturing a highly efficient polysilicon thin film solar cell.
[0038]
By the above method, a high-quality polysilicon thin film semiconductor device having a lower electrode (FIG. 1B) can be formed.
[0039]
Further, in order to use this device as a solar cell, it is necessary to form a semiconductor layer (second semiconductor layer) 5 of the opposite conductivity type on the crystalline silicon thin film, as shown in FIG. . As a result, a pn junction is formed between the crystalline silicon film (first semiconductor layer) 4a and the semiconductor layer (second semiconductor layer) 5 of the opposite conductivity type.
[0040]
The opposite conductivity type semiconductor layer 5 may be formed by epitaxial growth using LP-CVD (low pressure CVD). Alternatively, microcrystalline silicon or amorphous silicon may be formed by a P-CVD (plasma CVD) method. Further, the semiconductor layer does not necessarily need to be a crystalline silicon semiconductor. As is well known, this portion can be formed as a heterojunction by using microcrystalline silicon or an amorphous silicon-based alloy (SiC, SiO, SiN) or the like. In this case, it was confirmed that the surface recombination was effectively reduced by the effect of carrier repulsion at the heterojunction.
[0041]
By forming the transparent electrode layer 6 and the electrode layer serving as the extraction electrode 7 on the upper portion, a solar cell structure can be obtained. The transparent electrode layer 6 may be anything as long as it has transparency and conductivity. For example, ITO, ZnO, SnO ₂ or the like can be used. A metal such as Al is preferably used for the electrode layer serving as the extraction electrode 7. In some cases, it is also effective to form the direct extraction electrode 7 on the semiconductor layer 5 of the opposite conductivity type and to form a passivation film such as SiO ₂ or SixNy on the surface of the semiconductor layer other than the extraction electrode portion. .
[0042]
The crystalline silicon thin film formed in this way is, of course, suitable for use as a solar cell element, but is generally applicable to semiconductor devices using the crystalline silicon thin film, such as forming TFT substrates, MEMS, and SOI substrates. Can be used.
[0043]
【Example】
Hereinafter, examples of the present invention will be described. The following examples are merely examples of the present invention, and the present invention is not limited to these examples.
[0044]
[Example 1]
In this example, an attempt was made to fabricate a crystalline silicon thin film solar cell using a crystalline silicon thin film crystallized on a glass substrate with a YAG laser as an active layer.
[0045]
First, an Al thin film is formed as an electrode layer 2 on a glass substrate 1, and a barrier 03 is formed thereon. In this embodiment, 10 nm of SiO ₂ is used for the barrier layer 3. An amorphous silicon layer 4 having a thickness of 1 μm was formed thereon by using the LP-CVD method. This amorphous silicon layer 4 is doped with boron as a p-type dopant in silicon.
[0046]
In this embodiment, diborane (B ₂ H ₆ ), which is a doping gas during LP-CVD formation, was used for mixing the dopant. For forming the amorphous silicon layer 4, not only LP-CVD but also any other method that can form amorphous silicon may be used. For example, methods such as cat-CVD (catalytic vapor phase chemical deposition), P-CVD, MBE (Molecular Beam Epitaxy), and sputtering are exemplified. Also, as a doping method, it is effective to form the substrate without doping, and then perform the doping by ion implantation.
[0047]
The amorphous silicon layer 4 was crystallized on this sample using the second harmonic (532 nm) of a YAG laser (Nd: YAG). The melting and crystallization using the YAG laser was performed using a well-known method of performing crystallization by operating a laser beam in one direction.
[0048]
By this crystallization, the crystallized thin-film silicon layer 4a was a characteristic polycrystal in which approximately 80% of the crystal grain boundaries were within 45 degrees with respect to the direction in which the laser was scanned. According to the SEM observation and the TEM observation, it was found that a thin film having no crystal grain boundary in the film thickness direction was formed in a crystal grain, that is, that a single grain was formed from the substrate to the thin film surface. It became clear. This is a great advantage for a solar cell which is a vertical device. This is because carriers generated in the active layer travel in the thickness direction and reach the pn junction, where they are converted into electrical energy. The existence of the crystal grain boundaries having a large number of recombination sites in the vertical direction greatly reduces the characteristics. Therefore, forming a thin film having no crystal grain boundaries crossing the vertical direction has a very significant meaning in the characteristics of the solar cell.
[0049]
On the thin film thus formed, as shown in FIG. 1C, an n-type crystalline silicon layer (a semiconductor layer of the opposite conductivity type: a second semiconductor layer) is epitaxially grown by LP-CVD. 5 was formed. This film thickness was 50 nm. Further, an ITO transparent conductive film (transparent electrode layer) 6 was formed as an anti-reflection film, and an extraction Al electrode (extraction electrode) 7 was further formed to obtain a solar cell.
[0050]
When the characteristics of the solar cell formed by the above method were evaluated, the open-circuit voltage was 622 mV, and an open-circuit voltage value comparable to that of a single-crystal bulk silicon solar cell was obtained. In addition, when the series resistance was estimated from the IV characteristics obtained in an environment where no simulated sunlight was irradiated, a linear characteristic was shown in a region of 800 mV or more, and the series resistance was sufficiently low at 0.3 Ωcm ^2. Value. From this, a low contact resistance was obtained between the electrode layer on the back side and the active layer, and the crystalline silicon thin film crystallized by the laser could be applied to the solar cell structure.
[0051]
Further, SIMS analysis (secondary ion analysis) revealed that a large amount of Al element was mixed in the barrier layer 3. The decrease in contact resistance is due to Al firing through the barrier layer.
[0052]
In parallel with this experiment, a quartz substrate was used instead of the glass substrate 1, and crystallization was performed by lamp heating. As a result, it was similarly confirmed that a sufficiently low contact resistance can be obtained on the back surface side.
[0053]
[Example 2]
In this embodiment, Ag is used for the back electrode layer 2 and SnO ² is used for the barrier layer 3. The experiment used the structure of Example 1 and the thickness of the barrier layer 3 was 20 nm. As a result, similarly to Example 1, the series resistance was found to be a sufficiently low value of 0.5 Ωcm ² .
[0054]
ITO barrier layer 03 Similarly, ZnO, SiN, SiON, even when using a SnO _2, it was confirmed that sufficiently low resistance 1 .OMEGA.cm ² below.
[0055]
Similar effects were obtained when Sb, Ni, Mo, Ti, Pt, Co, Zn, Cu, Au, Fe, and W were used in addition to Al and Ag for the back electrode layer.
[0056]
[Example 3]
A third embodiment will be described with reference to FIG.
[0057]
In this embodiment, Al is used for the back electrode layer. In FIG. 2A, first, an Al back electrode layer 09 was formed on a glass substrate 08, and a barrier layer 10 was formed of SiO ₂ . A non-doped amorphous silicon layer 11 having a thickness of 1 μm was formed thereon by sputtering.
[0058]
This was irradiated with a laser in the same manner as in Example 1 to perform crystallization to obtain a non-doped crystalline silicon layer 11a shown in FIG. 2B.
[0059]
Thereafter, an n-type microcrystalline silicon layer 12, which is a second semiconductor layer of the opposite conductivity type, is formed on the crystallized i-layer polysilicon layer 11a, and an Al electrode layer 13 is formed thereon. As a result of IV measurement, rectification was observed as in the case of the pn junction. From this, it was confirmed that Al was diffused into the polysilicon layer on the back side to be a p-type crystalline silicon layer.
[0060]
Also, when the amorphous silicon layer 11 doped with phosphorus at a concentration of 1 × 10 ¹⁷ (atom / cm ³ ) is crystallized, the rectifying property is similarly exhibited, and the back side is doped with a high concentration of p-type. I knew it was there.
[0061]
For this reason, when the polysilicon to be crystallized is a p-type conductivity type, a BSF structure that reduces recombination on the back surface can be manufactured, and a high-quality solar cell element can be manufactured. I found it.
[0062]
As a matter of course, it is also effective to use the above thin film for a bipolar transistor which is a vertical device.
[0063]
【The invention's effect】
As described above, according to the present invention, the following excellent effects can be obtained.
[0064]
In the crystalline thin film semiconductor device of the present invention, an electrode layer, a barrier layer, and a semiconductor layer are formed on a substrate, and the semiconductor layer is annealed by a laser or a lamp to a non-single-crystal layer formed on the barrier layer. , Or a layer whose crystallinity has been changed.
[0065]
According to this structure, when energy is applied to the non-single-crystal layer by a light beam to crystallize or change the crystallinity of the non-single-crystal layer to form a semiconductor layer (for example, a crystalline silicon film), an element constituting the electrode layer is a barrier. The electrode layer and the crystalline silicon layer are electrically connected to each other, and slightly penetrate into the back surface of the crystalline silicon film. In addition, the degree to which the constituent elements of the electrode layer penetrate the barrier layer and penetrate into the non-single-crystal layer, that is, the concentration is controlled by the material and thickness of the barrier layer. Without diffusion, it is possible to perform diffusion only in the vicinity of the back surface pole of the crystalline silicon layer. Further, the electrode material diffused in the crystalline silicon layer can be used as a dopant.
[0066]
Therefore, according to the present invention, a high-quality crystalline silicon layer in a vertical device such as a solar cell can be manufactured at low cost by using the crystalline silicon thin film constituting the lower electrode. A large-area crystalline thin-film semiconductor device such as a solar cell that can achieve a conversion efficiency of more than 10% can be easily manufactured.
[Brief description of the drawings]
FIGS. 1A and 1B show a manufacturing process of a crystalline silicon semiconductor device according to Embodiments 1 and 2 of the present invention. FIG. 1A is a schematic diagram showing a stage where amorphous silicon is formed, and FIG. The figure which shows the stage which gave energy and turned into crystalline silicon, (c) is a completion figure.
FIGS. 2A and 2B show a manufacturing process of a crystalline silicon semiconductor device according to a third embodiment of the present invention, wherein FIG. 2A is a schematic diagram showing a stage of forming up to amorphous silicon, and FIG. is there.
[Explanation of symbols]
1 Substrate 2 Electrode layer (backside electrode layer)
3 barrier layer 4 amorphous silicon layer (non-single crystal layer)
4a Crystalline silicon film (semiconductor layer)
5 Reverse conductivity type semiconductor layer (second semiconductor layer)
6 Transparent electrode layer 7 Extraction electrode

Claims (12)

A conductive electrode layer is formed on part or all of the substrate, and a barrier layer formed for the purpose of restricting diffusion of a material constituting the electrode layer is formed on the electrode layer, and a non-uniform electrode layer is formed on the barrier layer. A crystal layer is formed, and the non-single-crystal layer is annealed by a laser or a lamp, so that the non-single-crystal layer is changed to crystallinity or has a semiconductor layer in which crystallinity is changed. Crystal thin film semiconductor device. The crystal thin-film semiconductor device according to claim 1,
A crystal thin film semiconductor device, wherein the non-single-crystal layer of the semiconductor layer is annealed by a laser or a lamp having a continuous output. The crystalline thin film semiconductor device according to claim 1, wherein
A crystalline thin-film semiconductor device, wherein the semiconductor layer is in electrical contact with the electrode layer. The crystalline thin film semiconductor device according to claim 1,
A crystalline thin film semiconductor device, wherein all or a part of the electrode layer is made of Al or a compound thereof. The crystalline thin film semiconductor device according to claim 1,
A crystalline thin-film semiconductor device, wherein the semiconductor layer is polycrystalline. The crystal thin-film semiconductor device according to claim 5,
The semiconductor layer, when viewed from the top of the substrate, has a portion where no crystal grain boundary exists in a region whose radius is equal to or larger than a certain point on the surface of the semiconductor layer, and a cross section at that point. A crystal thin-film semiconductor device, wherein there is no crystal grain boundary crossing the direction. The crystal thin-film semiconductor device according to claim 5,
In the above-mentioned polycrystalline semiconductor layer, at least 80% of the crystal grain boundaries are parallel to the direction in which the laser or the lamp is scanned or a direction within 45 degrees with respect to the parallel direction. Thin film semiconductor device. The crystalline thin film semiconductor device according to claim 1,
A crystalline thin-film semiconductor device, wherein a single-crystal or non-single-crystal second semiconductor layer having a conductivity type different from that of the semiconductor layer is formed on all or at least a part of the upper portion of the semiconductor layer. The crystal thin-film semiconductor device according to claim 8,
A conductive antireflection layer that is transparent to visible light is formed on the second semiconductor layer, and an electrode is formed on a part of the upper part of the antireflection layer. Crystalline thin film semiconductor device. The crystalline thin film semiconductor device according to claim 1,
The above-mentioned electrode layer is made of Al, Ag, Sb, Ni, Mo, Ti, Pt, Co, Zn, Cu, Au, Fe or W, or a compound containing these elements, or a crystalline thin film semiconductor device. . The crystalline thin film semiconductor device according to claim 1,
A crystal thin-film semiconductor device, wherein the barrier layer is made of any one of silicon oxide, silicon nitride, silicon oxynitride, ITO, zinc oxide, and tin oxide. A photovoltaic device comprising the crystalline thin film semiconductor device according to claim 1.

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