KR101562191B1 - High efficiency solar cells - Google Patents

Abstract

The high efficiency solar cell of the present invention includes a photovoltaic power generation unit for generating charges by light absorption, first and second electrodes having different polarities for outputting photovoltaic power generated by the photovoltaic generation unit to an external load, And a conversion layer for converting ultraviolet rays not absorbed by the photovoltaic power generation unit into visible light and providing the converted ultraviolet light back to the photovoltaic power generation unit. The high efficiency solar cell of the present invention further includes a bias electrode for applying an electric field added to the photovoltaic power generation unit. According to the high efficiency solar cell of the present invention, a conversion layer for converting ultraviolet rays into visible light can be provided to further increase the photoelectric conversion efficiency. Also, since the charge generated by the bias voltage applied to the bias electrode with the bias electrode is rapidly collected and collected, the recombination of the electron-hole pairs is prevented to the utmost, and high energy conversion efficiency can be obtained.

Solar cell, efficiency, ultraviolet, visible light, bias, recombination,

Description

[0001] HIGH EFFICIENCY SOLAR CELLS [0002]

The present invention relates to a solar cell, and more particularly, to a solar cell having a conversion layer for converting ultraviolet rays into visible light, which can increase the photoelectric conversion efficiency and increase the bias voltage to the solar cell so that the charge generated by the light rapidly flows. And more particularly to an improved high efficiency solar cell capable of achieving high energy conversion efficiency by preventing recombination of electron-hole pairs as much as possible.

Solar power generation is an infinite clean power generation technology that produces electricity from sunlight. The photovoltaic power generation system includes a solar cell (module) that generates electricity by receiving sunlight, a power control unit that converts the generated direct current into AC, and a balance of system (BOS) such as a battery that stores the generated electricity. . A solar cell is basically a diode composed of pn junctions and is divided into various types according to the material used as the light absorbing layer. Solar cells using silicon as the light absorbing layer are classified into a crystalline substrate type solar cell and a thin film type solar cell. In addition, CdTe and CIS (CuInSe2) compound thin film solar cells, III-V solar cells, dye-sensitized solar cells, and organic solar cells are typical solar cells.

Thin film solar cells are silicon based, CuInSe2 based, and CdTe thin film solar cells, depending on the light absorption layer material used. Advantages of such thin film solar cells are that they can use low cost substrates such as glass or metal plate instead of expensive silicon substrates, It is possible to manufacture solar cells at low cost by minimizing material consumption through thin film deposition inside and outside of the micron. Another advantage is that a large-area module can be manufactured using an in-line process, thereby improving productivity and reducing manufacturing cost. The types of silicon thin film solar cells are variously classified according to the deposition temperature of the thin film, the type of substrate (glass, metal plate, ceramic, silicon substrate, etc.) used and the deposition method. Crystalline silicon thin film solar cells are classified into amorphous and crystalline silicon thin film solar cells according to the crystal characteristics of the light absorption layer, and crystal silicon thin film solar cells are classified according to the crystal size and the thickness of the light absorption layer.

The amorphous silicon (a-Si: H) thin film solar cell has a very low diffusion length of the carrier due to the characteristics of the material itself, and is very low in comparison with a single crystal (or polycrystalline) silicon substrate. The collection efficiency of electron-hole pairs is very low. In general, therefore, the amorphous silicon thin film solar cell has a light absorption layer composed of an intrinsic semiconductor layer to which no impurity is added, and a pin structure in which a p-type semiconductor layer having a high doping concentration is interposed between the n-type semiconductor layer and the p-type semiconductor layer. In this structure, the photoabsorption layer is depleted by the p-layer and the n-layer having a high doping concentration at the top and bottom, and an electric field is generated inside. Therefore, the electron-hole pairs generated from the light absorbing layer by the incident light are collected by the n layer and the p layer by the drift due to the internal electric field instead of diffusion, and the electric current is generated.

In the case of an ideal device, the electric field is generated uniformly inside and the electron-hole pair flow smoothly. However, in real devices, space charge density increases at the pi and ni interfaces due to defects existing in the light absorption layer, and electric field decreases in the light absorption layer. In general, when the solar cell is exposed to light, a characteristic degradation phenomenon (Staebler-Wronski effect) occurs. The characteristics of the solar cell decrease by up to 30% depending on the thickness and physical properties of the light absorption layer. In addition, light-soaking increases the density of dangling bonds inside the light absorbing layer and decreases the internal electric field, thereby further accelerating the recombination of the electron-hole pairs generated by the light, Deterioration occurs.

On the other hand, nanocrystal (nc-Si: H) silicon thin film solar cell is a boundary material between amorphous and monocrystalline silicon. Nanocrystalline silicon, which is often called microcrystalline silicon (μc-Si: H) do. Nanocrystalline silicon has a crystal size of several tens of nanometers to several hundreds of nanometers depending on the deposition method. Amorphous phases are often present at grain boundaries, and most of the carrier recombination occurs at crystal boundaries due to the high bonding density. However, the amorphous silicon thin film solar cell has no deterioration phenomenon. Such a nanocrystalline silicon thin film solar cell is manufactured in the same pin structure as an amorphous silicon thin film solar cell because the grain size of the nanocrystalline silicon is small and contains a large amount of amorphous matrix, Although it is larger than silicon, np structure alone is not sufficient for carrier collection by diffusion.

As for the price of each component of solar power system, it is known that the module occupies the largest portion of total system price with module (60%), peripheral (25%) and installation cost (15%). Module prices, which account for 60% of the total system price, consist of board (40%, silicon), solar cell manufacturing (25%) and module assembly (35%). Considering that the market share of silicon solar cells is very high, the high price of solar power generation systems is due to the high price of solar modules, ie, the high proportion of silicon substrates that make up solar cells. The biggest problem that PV technology is currently sitting on is the high price of the system, which is a major obstacle to the massive supply of photovoltaic power generation. Therefore, energy conversion efficiency is very important for solar cells.

It is an object of the present invention to provide a conversion layer for converting ultraviolet rays to visible light to further enhance the photoelectric conversion efficiency and to apply a bias voltage to the solar cell so that the charge generated by the light is rapidly collected and collected, And a high energy conversion efficiency can be obtained.

According to an aspect of the present invention, there is provided a high-efficiency solar cell. The high efficiency solar cell of the present invention includes: a photovoltaic power generation unit that generates charges by light absorption; First and second electrodes having different polarities for outputting the photovoltaic power generated by the photovoltaic generation unit to an external load; And a conversion layer for converting ultraviolet rays not absorbed by the photovoltaic power generation unit into visible light and providing the converted ultraviolet light back to the photovoltaic power generation unit.

In one embodiment, the reflective layer reflects visible light generated in the conversion layer to the optical power generator.

In one embodiment, the photovoltaic generation unit further includes a bias electrode for applying an electric field added to the photovoltaic power generation unit, wherein the electric charge generated in the photovoltaic generation unit is applied to an internal electric field and an applied electric field by a bias voltage applied to the bias electrode The electrons and holes are collected and flowed more quickly toward the first and second electrodes, thereby preventing the recombination of the electron-hole pairs, thereby achieving high energy conversion efficiency.

In one embodiment, the semiconductor device includes an insulating layer for electrically insulating the bias electrode.

In one embodiment, the photovoltaic power generation part includes a multi-layered light absorbing layer in which an intrinsic amorphous semiconductor film and an intrinsic microcrystalline semiconductor film are alternately repeated.

In one embodiment, the photovoltaic generator includes a heterojunction with intrinsic thin-layer (HIT) structure having an intrinsic thin film.

In one embodiment, the first and second electrodes have an integrated backside contact (IBC) structure.

In one embodiment, the photovoltaic generator includes a multi-layered antireflection film having a porous antireflection film or two or more porous antireflection films stacked.

According to the high efficiency solar cell of the present invention, a conversion layer for converting ultraviolet rays into visible light can be provided to further increase the photoelectric conversion efficiency. Also, since the charge generated by the bias voltage applied to the bias electrode with the bias electrode is rapidly collected and collected, the recombination of the electron-hole pairs is prevented to the utmost, and high energy conversion efficiency can be obtained. The high-efficiency solar cell of the present invention can be applied to various types of amorphous or crystalline silicon thin film type solar cells, and substrate type solar cells using single crystal or polycrystalline silicon substrates. In addition, a conversion layer and a bias electrode for converting ultraviolet rays to visible light are added to a compound thin film solar cell, a III-V solar cell, a dye-sensitized solar cell, and an organic solar cell of CdTe or CIS (CuInSe2) Can be implemented.

For a better understanding of the present invention, a preferred embodiment of the present invention will be described with reference to the accompanying drawings. The embodiments of the present invention may be modified into various forms, and the scope of the present invention should not be construed as being limited to the embodiments described in detail below. The present embodiments are provided to enable those skilled in the art to more fully understand the present invention. Therefore, the shapes and the like of the elements in the drawings can be exaggeratedly expressed to emphasize a clearer description. It should be noted that in the drawings, the same members are denoted by the same reference numerals. Detailed descriptions of well-known functions and constructions which may be unnecessarily obscured by the gist of the present invention are omitted.

1 and 2 are cross-sectional views illustrating a thin film solar cell according to a first embodiment of the present invention.

1, a thin film solar cell 40 according to a first embodiment of the present invention includes a conversion layer 90 for converting ultraviolet rays into visible light to a thin film solar cell 40 having a pin superstrate structure, Thereby realizing a high-efficiency solar cell. In the thin film solar cell 40, a rear reflective film 92 and a conversion layer 90 are deposited on a substrate 47, and a photovoltaic power generation unit 41 is formed thereon. The photovoltaic power generating portion 41 is formed by stacking a light absorbing layer 42 (for example, an intrinsic amorphous silicon film) and a first conductive semiconductor film 43 (for example, p-type) Type semiconductor film 44 (for example, n-type). The first and second conductivity type semiconductor films 43 and 44 may be selected from, for example, a-Si or mc-Si or a-Si / mc-Si. The light absorption layer 42 may be composed of a single film made of an intrinsic amorphous semiconductor film, but it may be composed of a multi-layer structure in which an intrinsic amorphous semiconductor film and an intrinsic microcrystalline semiconductor film are alternately repeated. A transparent conductive film 45 is provided as a first electrode on the first conductive type semiconductor film 43 and another transparent conductive film 46 is formed on the second conductive type semiconductor film 44 Respectively. The first and second electrodes are electrically connected to an external load 36, for example, an electric power consuming device that consumes photovoltaic power or an attractive charge device for storing the generated photovoltaic power.

When light is incident on the light absorbing layer 42 through the transparent electrode 45 and the first conductive type semiconductor film 43, electron-hole pairs are generated, and the first conductive type semiconductor film 43 and the second conductive type semiconductor film 43, (44). At this time, ultraviolet rays not absorbed by the light absorbing layer 42 are converted into visible light in the conversion layer 90, reflected by the rear reflective layer 92, and then incident toward the light absorbing layer 42. Thus, photoelectric conversion efficiency of the photovoltaic power generation unit 41 can be increased. The transparent conductive film 46 functioning as the second electrode may be omitted and the rear reflective film 92 may be used as the second electrode. In this case, the rear reflective film 92 is made of a material having high conductivity and reflectivity, and has a textured structure so as to increase the reflection area, such as an embossing or a curved shape.

The thin film solar cell 40 having the pin superstructure structure as described above can be manufactured by providing a conversion layer 90 on a thin film solar cell 50 having a nip substrate structure as shown in FIG. 2 to realize a high efficiency solar cell . The thin film solar cell 50 having the nip substrate structure has basically the same structure and operating characteristics as the thin film solar cell 40 having the pin super straight structure described above. However, since the thin film solar cell 50 having the nip substrate structure is made incident through the back surface of the substrate 57, the stacking order of the semiconductor films constituting the photovoltaic power generating unit 51 is reversed. That is, a transparent conductive film 55 is laminated on a substrate 57 (the substrate is made of glass, for example, as a light transmitting substrate), and a first conductive type semiconductor film 53 and a light absorbing layer 52 are formed thereon, And the second conductive type semiconductor film 54 are sequentially stacked. A transparent conductive film 56 is stacked thereon, and a conversion layer 90 and a rear reflective film 92 are sequentially stacked.

On the other hand, in a general solar cell, the electron-hole pairs generated in the photovoltaic generation unit in response to the optical input are mostly drifted by an internal electric field (an electric field generated by depletion of the p layer and the n layer). However, the electron-hole pairs flowing by the internal electric field are recombined due to various causes in the course of flowing. The higher the recombination ratio, the lower the energy conversion efficiency. In order to overcome such a problem, the high efficiency solar cell of the present invention applies the added electric field by the bias voltage to the solar cell so that the charge generated by the light swiftly flows and collects, thereby preventing the recombination of the electron- The conversion efficiency can be obtained.

FIGS. 3 and 4 are cross-sectional views illustrating a thin film solar cell according to a second embodiment of the present invention.

Referring to FIG. 3, a bias electrode 34 is provided in a thin film solar cell 40 having a pin superstrate structure as one embodiment of the present invention to realize a high efficiency solar cell. The thin film solar cell 40 deposits a bias electrode 34 on a substrate 47 and deposits an insulating film 32 thereon. The rear reflective film 92, the conversion layer 90, and the photovoltaic power generation unit 41 are formed on the insulating film 32. The structure of the photovoltaic power generating unit 41 is the same as that described with reference to Fig.

When light is incident on the light absorbing layer 42 through the transparent electrode 45 and the first conductive type semiconductor film 43, electron-hole pairs are generated, and the first conductive type semiconductor film 43 and the second conductive type semiconductor film 43, (44). At this time, the bias electrode 34 is driven by receiving a voltage from the bias power source 30 and adds an electric field by a bias voltage to an internal electric field generated between the first and second conductive type semiconductor films 43 and 44 . Therefore, the generated electron-hole pairs are rapidly separated and collected by the electric field added by the internal electric field and the bias voltage, thereby preventing the recombination of the electron-hole pairs to the utmost. At this time, the ultraviolet ray passing through the photovoltaic power generation unit 41 is converted into visible light in the conversion layer 90, reflected by the rear reflective film 92, and incident on the light absorption layer 42.

As described above, the high-efficiency solar cell 40 according to the second embodiment of the present invention can convert ultraviolet rays into visible light and reflect the light to the light absorption layer to increase the light absorptivity and quickly generate the electric charges generated by the electric field added by the bias voltage By separating and collecting, the recombination of the electron-hole pairs is prevented to the utmost, and the overall photoelectric conversion efficiency can be maximized. The thin film solar cell 40 having the pin superstructure structure as described above is obtained by providing the conversion layer 90 on the thin film solar cell 50 having the nip substrate structure as shown in FIG. 4 to realize a high efficiency solar cell . Since this modified structure is already described with reference to FIG. 2, repeated description is omitted.

5 is a cross-sectional view illustrating a substrate type solar cell having an HIT structure according to a third embodiment of the present invention.

Referring to FIG. 5, in a third embodiment of the present invention, conversion layers 90 and 94 are formed on a crystalline substrate type solar cell 60 having a heterojunction with intrinsic thin-layer (HIT) structure having an intrinsic thin film A bias electrode 34 is provided to realize a high-efficiency solar cell. The HIT-structured substrate type solar cell 60 includes an intrinsic semiconductor film 69 (for example, an intrinsic amorphous silicon film) on the surface of the crystal semiconductor substrate 68 (for example, an n-type single crystal silicon substrate) Film and an antireflection film 80 thereon are sequentially formed. In order to increase the light absorption rate, the antireflection film 80 is made of porous silicon having a porous structure on the textured surface of the pyramid structure. The antireflection film 80 may be formed of a single porous antireflection film, but may have a multi-layer structure in which two or more porous antireflection films having the same refractive index or different from each other are overlapped to increase the light absorption rate.

As the back surface of the substrate 68, the photovoltaic generation portion 61 and the semiconductor films for constituting the first and second electrodes are provided adjacent to each other with a gap therebetween. An intrinsic semiconductor film 63 (for example, an intrinsic amorphous silicon film) and a first conductive type semiconductor film 65 (for example, an amorphous silicon film) are sequentially formed on one surface of the substrate 68 in order to constitute the first electrode, a p-type amorphous silicon film) and a conductive film 67 (for example, a transparent conductive film) functioning as a first electrode are laminated. An intrinsic semiconductor film 62 (for example, an intrinsic amorphous silicon film) and a second conductive type semiconductor film 64 (for example, an amorphous silicon film) are sequentially formed on another area on the back surface of the substrate 68, an n-type amorphous silicon film) and a conductive film 66 (for example, a transparent conductive film) functioning as a second electrode are laminated. The conductive films 67 and 66 functioning as the first and second electrodes may be formed of, for example, a transparent conductive oxide film (TCO) such as ITO, SnO2, ZnO, or the like. Although not shown in the drawing, each of the conductive films 67 and 66 may be formed of a metal electrode such as Al or Ag as a collector electrode.

In order to improve the pn junction property, the substrate type solar cell 60 having the HIT structure has a structure in which a substrate 68 made of n-type single crystal silicon and a first conductivity type semiconductor film 65 made of a p-type amorphous silicon film (HIT) structure in which an intrinsic semiconductor film 63 composed of an intrinsic amorphous silicon film is provided. Type semiconductor film 64 composed of an intrinsic semiconductor film 62 composed of an intrinsic amorphous silicon film and an n-type amorphous silicon film on the back surface of a substrate 68 made of n-type single crystal silicon, (Back Surface Field) structure. The conversion layers 94 and 90 and the rear reflective films 96 and 92 are stacked on the transparent conductive films 67 and 66 functioning as the first and second electrodes, (32) and a bias electrode (34) are sequentially stacked.

When light is incident on the substrate 68 through the antireflection film 80 and the intrinsic semiconductor layer 69, electron-hole pairs are generated and the first and second conductivity type semiconductor films 65 and 64 And flows separately. At this time, the bias electrode 34 is driven by receiving a voltage from the bias power source 30 and adds an electric field by a bias voltage to an internal electric field generated between the first and second conductive type semiconductor films 65 and 64 . Therefore, the generated electron-hole pairs are rapidly separated and collected by the electric field added by the internal electric field and the bias voltage, thereby preventing the recombination of the electron-hole pairs to the utmost. At this time, the ultraviolet ray passing through the photovoltaic power generation unit 41 is converted into visible light in the conversion layer 90, reflected by the rear reflective film 92, and incident on the light absorption layer 42.

As described above, the high efficiency solar cell 60 according to the third embodiment of the present invention converts ultraviolet rays into visible light, reflects the visible light to the light absorbing layer, increases the light absorption rate, and quickly generates the electric charges generated by the electric field added by the bias voltage By separating and collecting, the recombination of the electron-hole pairs is prevented to the utmost, and the overall photoelectric conversion efficiency can be maximized.

6 is a cross-sectional view illustrating a substrate type solar cell having a BIC structure according to a fourth embodiment of the present invention.

Referring to FIG. 6, conversion layers 90 and 94 and a bias electrode 34 are formed on a crystalline substrate type solar cell 70 having an integrated backside contact (IBC) structure integrated in a fourth embodiment of the present invention. Thereby realizing a high-efficiency solar cell. The substrate-type solar cell 70 of the IBC structure is provided with a crystalline semiconductor substrate 78 (for example, an n-type single crystal silicon substrate). A via hole 77 is formed in the substrate 78 so as to extend from one surface to the other surface. An intrinsic semiconductor film 72 (for example, an intrinsic amorphous silicon film) is stacked on one surface and back surface of the substrate 78 and on the side surface of the via hole 77 and the intrinsic semiconductor film 72 A first conductive semiconductor film 74 (for example, a p-type amorphous silicon film) is formed so as to reach the back surface of the substrate 78 through the upper portion of the via hole 77 and the via hole 77. The second conductivity type semiconductor film 73 (for example, an n-type amorphous silicon film) is formed on the back surface of the substrate 78 with an interval around the via hole 77 as a center. An antireflection film 80 is formed on the first conductive type semiconductor film 74 formed on one surface of the substrate 78. The antireflection films 75 and 76 are formed below the second conductive type semiconductor film 73 formed on the back surface of the substrate 78 and below the first conductive type semiconductor film 78 extending to the lower portion of the via hole 77, ). The antireflection film 76 laminated below the first conductive type semiconductor film 74 in the lower portion of the substrate 78 serves as the first electrode and the antireflection film 76 stacked below the second conductive type semiconductor film 73 (75) functions as a second electrode. Although not shown in the figure, each of the antireflection films 76 and 75 may be a metal electrode such as Al or Ag. The conversion layers 90 and 94 and the rear reflection films 92 and 96 are sequentially formed below the antireflection films 76 and 75 functioning as the first and second electrodes and the antireflection films 75 and 75 functioning as the second electrodes The insulating film 32 and the bias electrode 34 are sequentially stacked under the rear reflective film 96 located at the bottom of the rear reflective film 96.

When light is incident on the substrate 78 through the antireflection film 80 and the first conductivity type semiconductor layer 74, electron-hole pairs are generated and the first conductivity type semiconductor film 74 and the second conductivity type semiconductor film 73). At this time, the bias electrode 34 is driven by receiving a voltage from the bias power source 30 and adds an electric field by a bias voltage to an internal electric field generated between the first and second conductivity type semiconductor films 74 and 73 . Therefore, the generated electron-hole pairs are rapidly separated and collected by the electric field added by the internal electric field and the bias voltage, thereby preventing the recombination of the electron-hole pairs to the utmost. At this time, the ultraviolet rays passing through the photovoltaic power generating unit 71 are converted into visible rays by the conversion layers 90 and 94, reflected by the rear reflecting films 92 and 96, and incident on the light absorbing layer 42.

As described above, the high-efficiency solar cell 70 according to the fourth embodiment of the present invention can convert ultraviolet rays into visible light, reflect the light to a light absorption layer, increase the light absorption rate, and rapidly generate the electric charges generated by the electric field added by the bias voltage By separating and collecting, the recombination of the electron-hole pairs is prevented to the utmost, and the overall photoelectric conversion efficiency can be maximized.

The above-described high efficiency solar cell of the present invention can be applied to various types of amorphous or crystalline silicon thin film type solar cells, substrate type solar cells using monocrystalline or polycrystalline silicon substrates, as well as the above embodiments. In addition, a high efficiency solar cell can be realized by adding a bias electrode to a compound thin film solar cell of CdTe or CIS (CuInSe2), a III-V solar cell, a dye sensitized solar cell, or an organic solar cell.

The embodiments of the high efficiency solar cell of the present invention described above are merely illustrative and those skilled in the art will appreciate that various modifications and equivalent embodiments are possible without departing from the scope of the present invention. It will be possible. Accordingly, it is to be understood that the present invention is not limited to the above-described embodiments. Accordingly, the true scope of the present invention should be determined by the technical idea of the appended claims. It is also to be understood that the invention includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the appended claims.

1 and 2 are cross-sectional views illustrating a thin film solar cell according to a first embodiment of the present invention.

FIGS. 3 and 4 are cross-sectional views illustrating a thin film solar cell according to a second embodiment of the present invention.

5 is a cross-sectional view illustrating a substrate type solar cell having an HIT structure according to a third embodiment of the present invention.

6 is a cross-sectional view illustrating a substrate type solar cell having a BIC structure according to a fourth embodiment of the present invention.

Description of the Related Art [0002]

10: solar cell 12: photovoltaic power generation unit

14: first electrode 16: second electrode

18: load 20: solar cell

22: photovoltaic power generation unit 24: first electrode

26: second electrode 30: bias power source

32: insulating film 34: bias electrode

36: load 40: solar cell

41: photovoltaic power generation unit 42: light absorbing layer

43: first conductivity type semiconductor film 44: second conductivity type semiconductor film

45: transparent conductive film 46: rear reflective film

47: substrate 50: solar cell

51: photovoltaic power generation unit 52: light absorbing layer

53: first conductivity type semiconductor film 54: second conductivity type semiconductor film

55: transparent conductive film 56: rear reflective film

57: substrate 60: solar cell

61: photovoltaic power generation unit 62: intrinsic semiconductor film

63: intrinsic semiconductor film 64: second conductivity type semiconductor film

65: first conductivity type semiconductor film 66: conductive film

67: conductive film 68: crystalline semiconductor substrate

69: intrinsic semiconductor film 70: solar cell

71: photovoltaic power generation unit 72: intrinsic semiconductor layer

73: second conductivity type semiconductor film 74: first conductivity type semiconductor film

75: Antireflection film 76: Antireflection film

78: crystal semiconductor substrate 80: antireflection film

90: conversion layer 92: rear reflection film

94: conversion layer 96: rear reflection film

Claims (8)

A photovoltaic power generation unit for generating charges by light absorption; First and second electrodes provided on the upper and lower surfaces of the photovoltaic generation unit to output the photovoltaic power generated by the photovoltaic generation unit to an external load and having different polarities; A conversion layer formed on one side of the first and second electrodes so as to convert ultraviolet rays not absorbed by the photovoltaic power generation unit into visible light and supply the converted ultraviolet light to the photovoltaic generation unit; A bias electrode provided corresponding to the conversion layer for applying an electric field to the photovoltaic generation unit; And An insulating layer provided between the conversion layer and the bias electrode to electrically isolate the bias electrode; And a high-efficiency solar cell. The method according to claim 1, And a reflective layer for reflecting the visible light generated in the conversion layer to the photovoltaic power generation unit. delete delete The method according to claim 1, The photovoltaic power generation unit Layer structure in which an intrinsic amorphous semiconductor film and an intrinsic microcrystalline semiconductor film are alternately repeated. The method according to claim 1, The photovoltaic power generation unit And a heterojunction with intrinsic thin-layer (HIT) structure having an intrinsic thin film. The method according to claim 1, Wherein the first and second electrodes have an integrated backside contact (IBC) structure. The method according to claim 1, Wherein the photovoltaic power generator comprises a multi-layered antireflection film in which one porous antireflection film or two or more porous antireflection films are stacked.

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