JP2000196118A - Manufacture of solar battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing a solar battery, in which the interface section between the i-type semiconductor layer (i-layer) and n-type semiconductor layer (n-layer) of a photovoltaic semiconductor is constructed in a texture structure and which exerts light-confining effects. SOLUTION: At manufacturing of a solar battery by forming a photovoltaic semiconductor 13 by successively laminating a p-type semiconductor layer (p-layer) 10, an i-layer 11, and an n-layer 12 all of which are amorphous or microcrystalline layers on a first electrode layer 9 and a second electrode layer 14 on the semiconductor 13, fine particles (fog-like particles) 15 are made to adhere to the surface of the i-layer 11, by exposing the surface of the layer 11 to an atmosphere containing floating fine particles (fog particles 15) after the layer 11 is formed. After the particles 15 adhere to the surface of the layer 11, the partial surface of the layer 11, to which the particles 15 do not adhere, is etched with plasma by exposing the surface of the layer 11 to the plasma so that the interface section A between the layers 11 and 12 is constructed into a texture structure.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a thin-film solar cell comprising a photovoltaic semiconductor formed by laminating amorphous or microcrystalline semiconductor layers. The formation of a texture structure.

[0002]

2. Description of the Related Art Conventionally, a thin-film solar cell of this type has a structure substantially as shown in FIG. 5 in the case of a glass substrate type.

[0003] This solar cell has a glass substrate 1 on the light-receiving surface side.
An electrode layer 2 made of a transparent conductive film is formed thereon, and a p-layer made of an amorphous or microcrystalline semiconductor layer is formed on the electrode layer 2.
Semiconductor layer (hereinafter referred to as p layer) 3, i-type semiconductor layer (hereinafter referred to as i-layer) as power generation layer 4, n-type semiconductor layer (hereinafter referred to as n-layer)
A photovoltaic semiconductor 6 is formed by laminating layers 5), and an electrode layer 7 of a metal electrode film as a back electrode is formed on the semiconductor 6, that is, on the n-layer 5.

In an actual solar cell, the p-layer 3
In some cases, a buffer layer may be provided between the buffer layer and the i-layer 4.

[0005]

In this type of conventional solar cell, the light incident on the semiconductor 6 is effectively converted into a current to improve the photoelectric conversion efficiency. Etching on the back with acid or alkali solution,
Light is confined in the semiconductor 6 by making this back surface a texture structure.

Alternatively, by adjusting the forming conditions,
The back surface of the first electrode layer 2 has a textured structure and the semiconductor 6
Light is confined within.

However, in these cases, the electrode layer 2 becomes thicker, and the amount of light incident on the i-layer 4 is rather reduced due to the absorption of light by the layer 2, so that a texture structure is formed on the back side of the i-layer 4. It is most desirable that light be confined within the semiconductor 6.

Then, i on the back side of the i-layer 4 of the semiconductor 6
It is conceivable that the interface between the layer 4 and the n-layer 5 or the interface between the n-layer 5 and the electrode layer 6 may have a textured structure. Conventionally, this type of solar cell cannot be manufactured with a textured structure at the interface thereof because of the inability to form such irregularities.

The present invention is directed to a solar cell having a high light confinement effect in which the interface between the i-layer and the n-layer of the photovoltaic semiconductor or the interface between the n-layer and the electrode layer on the back side has a textured structure. A manufacturing method is provided.

[0010]

According to a first aspect of the present invention, there is provided a method of manufacturing a solar cell according to the present invention, wherein after forming an i-layer, the surface of the i-layer is exposed to a floating atmosphere of fine particles. The fine particles adhere to the surface of the i-layer by exposure, and after the fine particles are adhered, the surface of the i-layer is exposed to plasma to etch the non-adhered portion of the fine particles of the i-layer. To form a texture structure at the interface between the i-layer and the n-layer.

Therefore, the non-adhered portion of the fine particles of the i-layer is accurately etched by the combination of the adhesion of the fine particles and the plasma etching which is easy to control, instead of the etching by the acid or alkali solution, and the desired surface is formed on the i-layer. Can be manufactured in which the fine irregularities are uniformly formed and the interface between the i-layer and the n-layer of the photovoltaic semiconductor has a textured structure.

Further, in the method for manufacturing a solar cell according to the present invention, after forming the n-layer, the surface of the n-layer is exposed to a floating atmosphere of the fine particles so that the fine particles adhere to the surface of the n-layer. After adhering the fine particles, the surface of the n-layer is exposed to plasma to plasma-etch the non-adhered portion of the n-layer, and fine irregularities are formed on the surface of the n-layer by the plasma etching to form the n-layer and the second electrode. The interface between the layer and the layer has a texture structure.

Therefore, the combination of the attachment of the fine particles and the plasma etching in the same manner as in claim 1 allows the amorphous or microcrystalline n-layer of the photovoltaic semiconductor to be connected to the second electrode layer as the back electrode. An interface portion is formed in a texture structure, and a solar cell in which an interface portion between the n-layer of the photovoltaic semiconductor and the second electrode layer on the back surface has a texture structure can be manufactured.

The fine particles are desirably mist particles of water. At this time, the plasma etching is desirably an atmospheric pressure glow discharge plasma etching which can be performed at atmospheric pressure and normal temperature.

The average particle diameter of the fine particles is 0.2-1.
00 μm, i
It is optimal from the thickness of the layer and the n layer.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIGS. (1) First, the manufacture of a solar cell in which a texture structure is formed at the interface between the i-layer and the n-layer of the photovoltaic semiconductor will be described with reference to FIGS. In this embodiment, the glass substrate type single solar cell having the structure shown in FIG. 2 is manufactured by the manufacturing steps shown in FIGS.

In this solar cell, a first electrode layer 9 of a transparent conductive film is formed on a glass substrate 8 on the light-receiving surface side.
An amorphous or microcrystalline p layer 10, an i layer 11,
The photovoltaic semiconductor 13 is formed by laminating the n-layers 12, and a second electrode layer 14 of, for example, an Al electrode film is formed as a back electrode on the semiconductor 13, that is, on the n-layer 12. .

The difference between the solar cell of FIG. 2 and the conventional cell of FIG. 5 is that fine irregularities are formed on the surface of the i-layer 11 and the interface portion A between the i-layer 11 and the n-layer 12 has a textured structure. Thus, fine irregularities appear on the surface of the n-layer 12, and the interface B between the n-layer 12 and the electrode layer 14 is also formed into a texture structure.

Next, a method for manufacturing this solar cell will be described. First, a glass substrate 8 is prepared as shown in FIG. 1A, and a first electrode layer 9 shown in FIG. 1B is formed on the glass substrate 8 by sputtering or CVD.

Further, as shown in FIGS. 1C and 1D, the p-layer 1 is formed on the first electrode layer 9 by a plasma CVD method.
The 0 and i layers 11 are sequentially laminated.

At this time, the i-layer 11 may be a thin film layer of an amorphous semiconductor. However, considering that fine irregularities on the order of microns (μm) are formed on the surface by plasma etching described later, the i-layer 11 is used as a power generation layer. It is more practical to use a microcrystalline semiconductor thin film layer with a required thickness of the micron order than a amorphous semiconductor thin film layer with a required film thickness on the order of Angstroms (Å), rather than a thin film layer. In this embodiment, for example, it is formed by a thin layer of microcrystalline silicon.

Next, after the i-layer 11 is formed, fine particles are adhered to the surface of the i-layer 11 to form fine irregularities on the surface of the i-layer 11 with a depth substantially equal to the average particle diameter of the fine particles.

The fine particles prevent plasma etching of the portion where the i-layer 11 is adhered, and may be various liquid or solid particles. However, when the etching is completed, the fine particles evaporate and the removal processing can be omitted. Considering the advantages such as the above, it is preferable to form by water (pure water) mist particles.

When the fine particles are mist particles, since the mist particles can be formed with a high degree of granularity on the order of microns by the technique of spraying (spraying) antistatic mist in the field of semiconductor manufacturing, the i-layer 11 After formation, in a so-called clean room, water (pure water) in a liquid pressurized tank is sprayed from a spray nozzle into the room by a method similar to the above-described method of spraying mist, and mist particles having a desired particle size on the order of microns are formed. Is generated and the i-layer 11 is exposed to the floating space of the fog particles.
As shown in (e), the mist particles 15 having an average particle diameter of about half or less of the thickness of the i-layer 11 are adhered to the surface thereof.

At this time, the mist particles 15 on the surface of the i-layer 11
For example, the electrode layer 9, the p-layer 10, the i-layer 1
The glass substrate 8 in the state shown in FIG. 1 (d) in which the i-layer 11 is formed is housed in a sealed container and carried into a clean room, and the lid of the sealed container is opened and closed in the clean room filled with the mist particles 15. This is performed by regulating the time during which the fog particles 15 adhere to the surface (the time during which the fog particles 15 are left in the fog).

According to this regulation, the average adhesion particle diameter and the average adhesion interval of the mist particles 15 on the surface of the i-layer 11 are controlled to desired sizes.

After the attachment of the mist particles 15, the process proceeds to a plasma etching step, and the portion of the i-layer 11 where the mist particles 15 are not attached (non-adhered portion) is etched.

This plasma etching is performed using atmospheric pressure glow discharge plasma in order to prevent instantaneous evaporation due to heating or decompression of the mist particles 15.

This atmospheric-pressure glow discharge plasma can be obtained, for example, by the method described in "Paper Collection of 1995 Annual Meeting of the Kansai Regional Scientific Meeting of the Japan Society of Precision Engineering", "Si by atmospheric pressure CVD using rotating electrodes".
Study on High-Speed Thin Film Formation (2nd Report) ”(II-287)
To 288), and has a feature that it is generated by a generator thereof even at atmospheric pressure and at room temperature (normal temperature).

Then, the glass substrate 8 in the state of FIG. 1E is accommodated in an atmospheric pressure glow discharge plasma generator,
The surface of the i-layer 11 is exposed to atmospheric-pressure glow discharge plasma under the conditions of atmospheric pressure and normal temperature to perform atmospheric-pressure glow discharge plasma etching.

At this time, the portion of the i-layer 11 to which the mist particles 15 adhere is protected from the plasma by the mist particles 15 and is not etched, and only the non-adhered portion of the mist particles 15 of the i-layer 11 is plasma-etched. .

By this selective etching, the i-layer 11
As shown in FIG. 1F, fine irregularities of the order of microns having a depth of about half or less the thickness of the i-layer 11 are formed on the surface thereof, and the mist particles 15 on the surface are generated by plasma etching. After the etching is completed by heat or the like, it evaporates and disappears.

Next, as shown in FIG. 1G, an n-layer 12 is deposited on the i-layer 11 by a plasma CVD method to form a photovoltaic semiconductor 13, and the i-layer 11 and the n-layer 12 are formed. A texture structure with fine irregularities is formed at the interface portion A.

Thereafter, a second electrode layer 14 made of an Al electrode film is formed on the n-layer 12 by a sputtering method to complete a solar cell.

Therefore, by the combination of the attachment of the mist particles 15 and the etching by the atmospheric pressure glow discharge plasma,
It is possible to form a fine and uniform texture structure of micron-order uniform unevenness on the interface portion A between the i-layer 11 and the n-layer 12 which has not been conventionally possible, and to provide a solar cell of this kind having excellent characteristics. it can.

In this case, since the texture structure is formed at the position on the back side of the i-layer 11 closest to the i-layer 11, the effect of confining light is extremely high, and the photoelectric conversion characteristics can be significantly improved.

(Other Embodiments) Next, n of the photovoltaic semiconductor
The production of a solar cell in which a texture structure is formed at the interface between the layer and the electrode layer on the back surface will be described with reference to FIGS. In this embodiment, FIG.
The solar cell of FIG. 4 is manufactured by the manufacturing process (g).

In these drawings, the reference numerals in FIGS. 1 and 2 with a dash (') indicate the same or corresponding components as those in FIGS. 1 and 2.

Then, as shown in FIG. 3A, a first electrode layer 9 'is formed on a glass substrate 8' by a sputtering method, and then, shown in FIGS. 3B, 3C and 3D. As shown in FIG. 3, a microcrystalline or amorphous p layer 1 is formed on an electrode layer 9 'by a plasma CVD method.
0 ′, i-layer 11 ′, and n-layer 12 ′ are sequentially deposited to form a photovoltaic semiconductor 13 ′.

At this time, the n-layer 12 'is formed to a thickness on the order of microns in consideration of etching.

Next, the surface of the n-layer 12 'is exposed to a floating atmosphere of the mist particles in the clean room, and the mist particles 15' are adhered to the surface of the n-layer 12 'as shown in FIG.

Then, the process proceeds to the plasma etching step, where the mist particles 15 'adhered under atmospheric pressure and normal temperature conditions.
Exposing the surface of layer 12 'to an atmospheric pressure glow discharge plasma;
By performing plasma etching, fine irregularities are formed on the surface of the n-layer 12 'as shown in FIG.

Thereafter, as shown in FIG.
A solar cell is completed by forming a second electrode layer 14 'on 2'.

At this time, a texture structure having fine irregularities is formed at the interface portion B 'between the n-layer 12' and the electrode layer 14 ', and this type of solar cell having excellent characteristics is provided as in the case of the first embodiment. can do.

In the case of this mode, plasma CVD
After the p, i, and n layers 10 ', 11', and 12 'are formed by the method and the photovoltaic semiconductor 13' is formed, the process proceeds to a plasma etching process to form a texture structure. As shown in FIG.
Compared to the case where the process shifts to the plasma etching step after forming the layer and a texture structure is formed at the interface between the i-layer and the n-layer, the control of the process is easier and this type of solar cell having excellent characteristics is stabilized. Has the advantage of mass production.

[0046]

Next, a method for manufacturing the above-described solar cells will be described with reference to specific examples of forming a texture structure and characteristic examples of the manufactured solar cells. (Embodiment 1) First, a specific example of the manufacturing method of the first embodiment will be described. In the photovoltaic semiconductor 13 of FIG. 2, the p-layer 10 and the n-layer 12 have an amorphous silicon (a-Si) layer and the i-layer 11 has a pin structure of a microcrystalline silicon layer.
(C), (d), and (g), the p, i, and n layers 1 are formed by the plasma CVD method under the forming conditions shown in Table 1 below.
0, 11, and 12 were formed.

[0047]

[Table 1]

In Table 1, Ts is a substrate temperature, power is a high frequency output, and pressure is a mixed gas pressure.

Further, as shown in the column of set film thickness in the table,
The p layer 10 is formed to have a thickness of 100 °, the i layer 11 is formed to have a thickness of 200 μm before plasma etching in consideration of the depth of the texture structure, and the n layer 12 is formed to have a thickness of 300 °. did.

Next, after the formation of the i-layer 11, FIG.
In the process of adhering the mist particles 15 of the atmospheric pressure class 10
Using a clean room with a volume of 100 m ³ or less, water in the liquid pressurized tank was discharged at an air flow rate of 50 l / h and an air pressure of 5
The spray was sprayed into the room from a spray nozzle at kg / cm ² to make the clean room a floating atmosphere of mist particles having an appropriate particle size in the range of 0.1 to 120 μm.

The floating atmosphere of the mist particles 15
When the surface of the layer 11 was exposed and the experiment was carried out, the average adhesion particle diameter and the average adhesion interval of the mist particles 15 on the surface of the i-layer 11 are shown in Table 2 below according to the time of being left in the atmosphere (leaving time in fog). It was confirmed that it became as shown.

[0052]

[Table 2]

Note that the average adhesion interval is a distance L between the surfaces of the mist particles 15 as shown in FIG.

As is apparent from Table 2,
For example, 0.5 m
When left for 2 seconds, the average adhered particle size is 0.1 μm on the surface of the i-layer 11.
m, the mist particles 15 adhere at an average adhesion interval of 0.1 μm, and are left for 300 seconds in a floating atmosphere of the mist particles having a particle size of 120 μm. Particles 15 adhere.

Next, in the plasma etching step of FIG. 1F, since the plasma generation area of the atmospheric pressure glow discharge plasma, that is, the area that can be etched at one time, is small, the i-layer to which the mist particles 15 adhere is The surface of No. 11 was etched under the etching conditions (processing control conditions) shown in Table 3 below.
Etching was performed at atmospheric pressure and normal temperature for each area of 1 cm × 5 cm to form fine irregularities.

[0056]

[Table 3]

In Table 3, the gap interval corresponds to the film forming gap described in the literature of the above-mentioned collection of papers, and the RF power density is the high-frequency power density of glow discharge.

After this plasma etching, n
The layer 12 was formed to form a texture structure at the interface portion A, and the second electrode layer 14 of an Al electrode film was formed by a sputtering method.

Various solar cells having different average particle diameters and average intervals of the mist particles 15 were formed in this way, and their photoelectric conversion characteristics were measured. The results shown in Table 4 below were obtained. Was.

[0060]

[Table 4]

Table 4 shows the average adhesion interval of the mist particles 15 /
Average adhesion particle size (interval / particle size) is 0.1 / 0.1, 0.2
/0.2,..., 120/120, are referred to as Example batteries A _{1 to} A _9. Each of these Example batteries A _{1 to} A ₉ and Comparative example battery A ₀ is provided with a photoelectric The measured current densities (normalized current densities) and conversion efficiencies (normalized conversion efficiencies) of the conversion are measured and compared as characteristics of solar cells.

[0062] Incidentally, after the comparative example cell A ₀ is formed p-layer, an i layer in the same manner as the Example battery A ₁ to A _9, an i layer surface exposed to the atmosphere without depositing the mist particles 15, then, n
And an electrode layer of an Al electrode film.

Then, the i-layer 1 is formed by plasma etching.
The uneven shape formed in No. 1 was evaluated by measuring the average depth and average interval of the unevenness by surface SEM observation and cross-sectional SEM observation.

Regarding the characteristics of the manufactured solar cells, their I (current) -V (voltage) characteristics were measured and evaluated as the normalized current and normalized conversion efficiency.

As is apparent from Table 4, the average depth and interval of the irregularities of the i-layer 11 have a correlation with the average adhesion particle diameter and the average adhesion interval of the mist particles 15, and are determined by them. Example batteries A _{2 to} A having a particle size of 0.2 to 100 μm, which is about half or less of the thickness (200 μm) of i-layer 11.
₈ the average interval of adhesion is also 0.2～100Myuemu, greater than that of Comparative Example battery A ₀ normalized conversion efficiency was found to be improved characteristics.

[0066] Incidentally, normalized current density of Example Battery _{A 9,}
It is considered that the reason why the normalized conversion efficiency is reduced is that the effect of confining light is reduced.

From these facts, it is possible to form irregularities on the front surface (actually, the back surface) of the i-layer 11 having a depth of about half or less of the thickness of the average adhering particle diameter of the mist particles 15 and the i-layer 11 and the n-layer 1
By forming a texture structure at the interface portion A with the surface layer 2, a solar cell with improved characteristics can be manufactured. In particular, it has been found that it is preferable to set the average adhesion particle size to 0.2 to 100 μm.

(Embodiment 2) Next, a specific example of the manufacturing method of the other embodiment will be described. In the case of this embodiment, the following Table 5 is obtained by the steps of (c), (d) and (e) of FIG.
Under each condition, each layer 1 of p, i, and n is formed by a plasma CVD method.
0 ′, 11 ′, 12 ′ were formed.

As in the case of the first embodiment, the p layer,
The n layers 10 'and 12' are a-Si layers, and the i layer 11 'is a microcrystalline silicon layer.

[0070]

[Table 5]

As is clear from the comparison between Table 5 and Table 1, in this embodiment, in order to form irregularities on the surface of the n-layer 12 ', the i-layer 11' is required as a power generation layer. It is formed to a thickness of 100 μm, and the n-layer 12 ′
It was formed to a thicker thickness of 200 μm.

Further, after the formation of the n-layer 12 ′, the process proceeds to the step of attaching the mist particles 15 ′ of FIG. 3E, and the conditions for spraying the mist using the clean chamber and the liquid pressure tank are the same as those in the first embodiment. Thus, the mist particles 15 ′ were attached to the surface of the n-layer 12 ′.

At this time, the relationship between the standing time of the mist particles 15 ′ and the average adhering particle diameter and the average adhering particle diameter were the same as in Table 2 above.

Next, in the plasma etching step shown in FIG. 3 (f), the surface of the n-layer 12 'is 1 cm.times.
Etching is performed at atmospheric pressure and room temperature in 5 cm regions, and n layer 1
Fine irregularities were formed on the surface of 2 ′ (the back surface as a solar cell), and then a second electrode layer 14 ′ of an Al electrode film was formed by a sputtering method.

Then, as in the case of the first embodiment, the mist particles 1
Various solar cells having different average particle diameters and average intervals of 5 ′ were formed, and their photoelectric conversion characteristics were measured. The results in Table 6 below were obtained.

[0076]

[Table 6]

The comparative battery B _{0 in} Table 6 is a solar battery manufactured under the same conditions as the comparative battery A _{0 in} Table 1, and the batteries B _{1 to} B ₉ of the comparative examples have the average particle size of the mist particles 15 ′. diameter, a solar cell manufactured by the average interval of adhesion in the same manner as in example battery a ₁ to a _9.

As is clear from Table 6, the n-layer 1
Even if the same micron-order irregularities as in Example 1 are formed on the surface (actually the back surface) of 2 ′ to form a texture structure at the interface B ′ between the n-layer 12 ′ and the electrode layer 14 ′,
A solar cell having improved characteristics can be manufactured in the same manner as in the above, and it has been found that in this case as well, it is preferable to set the average adhesion particle size to 0.2 to 100 μm.

By the way, the fine particles are in the i-layer 11 or the n-layer 1
It suffices to prevent etching of the adhering portion of 2 ′, and may be various liquid or solid particles other than water mist particles. Depending on the conditions of these fine particles, instead of plasma etching by atmospheric pressure glow discharge plasma, Alternatively, a conventional general plasma etching performed by heating or vacuuming the substrate may be performed to perform the etching process.

When the fine particles are not mist particles, the etching may be performed by the atmospheric pressure glow discharge plasma.

The p, i, and n layers may be various amorphous or microcrystalline semiconductor layers.

Further, it is not always necessary that the average adhesion particle diameter and the average adhesion interval of the fine particles such as the mist particles 15 and 15 'coincide with each other, and the average adhesion particle diameter and the average adhesion interval may be different.

[0083]

The present invention has the following effects. First, in the case of the manufacturing method according to claim 1, after the formation of the i-type semiconductor layer (i-layer 10), the surface of the i-layer 10 is exposed to a floating atmosphere of fine particles (fog particles 15) so that particles are formed on the surface of the i-layer 10. Then, the surface of the i-layer 10 is plasma-etched to form fine irregularities on the surface of the i-layer 10 to texture the interface portion A between the i-layer 10 and the n-type semiconductor layer (n-layer 11). Due to the structure, the interface portion A between the i-layer 10 and the n-layer 11 can be formed into a good texture structure by a combination of plasma etching that allows easy attachment and control of the particles 15 instead of etching with an acid or alkali solution. Thus, a solar cell having an extremely high light confinement effect can be manufactured.

In the case of the second aspect, fine irregularities are formed on the surface of the n-layer 12 'by plasma etching.
Since the interface portion B 'between the layer 12' and the second electrode layer 14 'has a textured structure, the n-layer is formed by a combination of the attachment of fine particles (fog particles 15') and plasma etching as in the case of claim 1. Interface portion B 'between 12' and electrode layer 14 '
Can be formed into a good texture structure, and a solar cell having a high light confinement effect can be manufactured.

In this case, the photovoltaic semiconductor 13 '
Since plasma etching is performed after the formation of each of the p, i, and n layers 10 ', 11', and 12 ', there is an advantage that the process can be easily controlled and the production can be stably performed.

Furthermore, in the case of the third aspect, since the fine particles are the water mist particles 15 and 15 'and the plasma etching is the atmospheric pressure glow discharge plasma etching, the solar cell can be manufactured by an extremely practical method. .

In the case of the fourth aspect, the most desirable texture structure can be formed because the average particle diameter of the attached fine particles is set to 0.2 to 100 μm.

[Brief description of the drawings]

FIGS. 1A to 1H are explanatory views of a manufacturing process according to an embodiment of the present invention.

FIG. 2 is a configuration diagram of a solar cell according to one embodiment of the present invention.

FIGS. 3A to 3G are explanatory views of a manufacturing process according to another embodiment of the present invention.

FIG. 4 is a configuration diagram of a solar cell according to another embodiment of the present invention.

FIG. 5 is a configuration diagram of a conventional solar cell.

[Explanation of symbols]

 9, 9 'First electrode layer 10, 10' P-type semiconductor layer (p-layer) 11, 11 'i-type semiconductor layer (i-layer) 12, 12' N-type semiconductor layer (n-layer) 13, 13 ' Electromotive force semiconductor 14, 14 'Second electrode layer A, A', B, B 'interface

Claims (4)

[Claims] 1. A photovoltaic semiconductor is formed by laminating an amorphous or microcrystalline p-type semiconductor layer, an i-type semiconductor layer, and an n-type semiconductor layer on a first electrode layer, respectively. When a solar cell is manufactured by forming a second electrode layer, after forming the i-type semiconductor layer, the surface of the i-type semiconductor layer is exposed to a floating atmosphere of fine particles, and the surface of the i-type semiconductor layer is After the particles are attached, the surface of the i-type semiconductor layer is exposed to plasma to plasma-etch the non-adhered portion of the i-type semiconductor layer, and the i-type semiconductor layer is removed by the plasma etching. A method for manufacturing a solar cell, characterized in that fine irregularities are formed on the surface to form a texture structure at an interface between the i-type semiconductor layer and the n-type semiconductor layer. 2. A photovoltaic semiconductor is formed by laminating an amorphous or microcrystalline p-type semiconductor layer, an i-type semiconductor layer, and an n-type semiconductor layer on a first electrode layer, respectively. When a solar cell is manufactured by forming a second electrode layer, after forming the n-type semiconductor layer, the surface of the n-type semiconductor layer is exposed to a floating atmosphere of fine particles, and the surface of the n-type semiconductor layer is After the particles are attached, the surface of the n-type semiconductor layer is exposed to plasma to plasma-etch the non-adhered portion of the n-type semiconductor layer, A method for manufacturing a solar cell, characterized in that fine irregularities are formed on the surface so that an interface between the n-type semiconductor layer and the second electrode layer has a textured structure. 3. The method according to claim 1, wherein the fine particles are mist particles of water, and the plasma etching is atmospheric pressure glow discharge plasma etching. 4. The method according to claim 1, wherein the average particle diameter of the fine particles is not more than half the thickness of the semiconductor layer to be plasma-etched.
4. The method for manufacturing a solar cell according to claim 1, wherein m is m.