KR101393092B1 - Ⅲ-ⅴ group compound solar cell and method for preparing the same - Google Patents

Abstract

The III-V compound solar cell of the present invention comprises a substrate; A back electrode layer formed on the substrate; A nanowire growth layer formed on the back electrode layer; A photoelectric conversion layer formed on the nanowire growth layer; And a transparent electrode layer formed on the photoelectric conversion layer, wherein the photoelectric conversion layer includes an n-type III-V compound nano wire (NW) formed on the nanowire growth layer, and a n-type III Lt; RTI ID = 0.0 > III-V < / RTI > The III-V compound solar cell can be laminated, has a wide band gap range, can exhibit high performance and high efficiency, and is economical.

Description

III-V GROUP SOLAR CELL AND METHOD FOR MANUFACTURING THE SAME Technical Field [0001] The present invention relates to a III-

The present invention relates to a III-V compound solar cell and a manufacturing method thereof. More specifically, the present invention uses a III-V group compound of a low-cost substrate and a nano wire structure to enable stacking, has a wide bandgap range, exhibits high performance and high efficiency, -V compound solar cell and a manufacturing method thereof.

In recent years, interest in renewable energy has been increasing due to environmental problems of the earth, depletion of fossil energy, waste treatment of nuclear power generation, and selection of location for new power plant construction. Among them, research on photovoltaic power generation Development is progressing actively both domestically and internationally.

A solar cell is a semiconductor device that converts solar energy directly into electric energy. It has a form of p-type semiconductor and n-type semiconductor, and its basic structure is similar to a diode.

When sunlight is irradiated onto a solar cell having a structure in which p-type and n-type semiconductors having different electrical properties are bonded to each other, an electron-hole pair is generated by light energy, and electrons and holes move An electromotive force is generated by a photovoltaic effect in which a current flows across the n-type semiconductor layer and the p-type semiconductor layer, and a current flows to a load connected to the outside.

In detail, when light is incident on the solar cell from the outside, the electron band of the p-type semiconductor is excited to the conduction band by the incident light energy, Type semiconductor, and electrons among the generated electron-hole pairs are transferred to the n-type semiconductor by an electric field existing between the pn junctions to supply current to the outside .

On the other hand, most of the solar cells currently in mass production are silicon solar cells, which use silicon (Si) as a semiconductor substrate, which is an indirect interband transition semiconductor, which is larger than the bandgap of silicon When light having energy is absorbed, there is a disadvantage that heat loss can be generated in addition to electron-hole pair generation.

In addition, in a solar cell using silicon, light having energy lower than the bandgap of silicon can not generate electron-hole pairs and is lost in the form of heat energy, so that the absorption rate of light is low, and 30% Is reflected on the surface of the silicon wafer as the substrate, and the efficiency of the solar cell is lowered.

In contrast, a solar cell using a group III-V compound has a variety of bandgaps, so that a compound cell having a different wavelength band to be absorbed by each of the solar cells is constructed using these characteristics, (tandem) structure, which is coupled with a tunnel junction, achieves higher energy conversion efficiency than a silicon solar cell.

Generally, a solar cell using a group III-V compound uses a substrate such as Ge or GaAs to increase the light-receiving area, but the manufacturing cost is increased because a Ge or GaAs substrate is expensive. In addition, when the thin film is manufactured, an expensive source (III-V group compound) is used in an excessive amount, which increases manufacturing cost. Therefore, a solar cell using a group III-V compound has been applied only to fields requiring special high performance and high efficiency. In order to lower the manufacturing cost compared to the same power, a condensing operation is performed through a low cost lens.

Therefore, a relatively small amount of a group III-V compound is used in comparison with a solar cell using a group III-V compound in the form of a thin film, as a method of achieving high efficiency through large-scale as well as low- There is a need for a technique capable of forming a solar cell (or a photo detector) on a low-cost substrate (a glass substrate, a flexible substrate, etc.).

An object of the present invention is to provide a III-V compound solar cell capable of being laminated and having a wide band gap range, exhibiting high performance and high efficiency, and a method for manufacturing the same.

It is another object of the present invention to provide an economical III-V compound solar cell using less III-V compounds compared to inexpensive substrates and thin films, and a method of manufacturing the same.

One aspect of the present invention relates to a group III-V compound solar cell. The III-V compound solar cell comprises a substrate; A back electrode layer formed on the substrate; A nanowire growth layer formed on the back electrode layer; A photoelectric conversion layer formed on the nanowire electrode layer; And a transparent electrode layer formed on the photoelectric conversion layer, wherein the photoelectric conversion layer includes an n-type III-V compound nano wire (NW) formed on the nanowire growth layer, and a n-type III Lt; RTI ID = 0.0 > III-V < / RTI >

In one embodiment, the nanowire growth layer comprises a conductive compound layer on which the conductive compound is deposited on the back electrode layer, and a conductive compound layer on the conductive compound layer, wherein the conductive compound layer is formed of gold (Au), platinum (Pt), silver (Ag), and palladium (Pd) And a catalyst particle layer made of a metal catalyst containing at least one metal catalyst.

In an embodiment, the conductive compound may include one or more of zinc oxide (ZnO), zinc oxide doped with aluminum (Al), ITO, graphene, and carbon nanotubes.

In an embodiment, the n-type III-V compound nanowire may be formed between the catalytic particles of the catalytic particle layer and the conductive compound layer.

In an embodiment, the transparent electrode layer may be formed by depositing a conductive compound on the photoelectric conversion layer so as to be connected to the upper end of the p-type III-V compound nano-wire.

In an embodiment, the photoelectric conversion layer may further include a dielectric surrounding the n-type III-V compound nanowire and the p-type III-V compound nanowire.

In an embodiment, the substrate may be a glass or a flexible substrate.

In an embodiment, the back electrode layer may be formed of a metal including at least one of molybdenum (Mo), tungsten (W), nickel (Ni), and copper (Cu)

In an embodiment, the n and p type III-V compound nanowires are n and p type In _xy Ga _{(1-x) y} Al _{1 -y} As _z P _{1 -z} (0 _{? X?} y? 1, 0? z? 1), InGaAs, or a combination thereof.

In an embodiment, the n and p-type III-V compound nanowires may have a diameter of 1 to 100 nm and a length of 1 to 20 m.

In an embodiment, the energy band gap range of the photoelectric conversion layer may be 0.3 to 2.1 eV.

In a specific example, the unit including the photoelectric conversion layer and the transparent electrode layer is repeatedly laminated two or more times, and the transparent electrode layer on which the unit is laminated is formed of a metal such as gold (Au), platinum (Pt), silver (Ag) Pd), and the energy bandgap of the stacked photoelectric conversion layer may become larger as the distance from the substrate increases.

In an embodiment, the unit including the dielectric layer, the nanowire growth layer, the photoelectric conversion layer, and the transparent electrode layer is repeatedly laminated on the transparent electrode layer one or more times on the transparent electrode layer. As the photoelectric conversion layer is further away from the substrate, The gap may be large.

Another aspect of the present invention relates to a method for producing the III-V compound solar cell. The method includes forming a nanowire growth layer on a substrate having a back electrode layer formed thereon; Growing an n-type III-V compound on the nanowire growth layer to form an n-type III-V compound nano wire and forming a p-type III-V compound on the n-type III- Group compound to form a p-type III-V compound nanowire to form a photoelectric conversion layer; And forming a transparent electrode layer on the photoelectric conversion layer.

In one embodiment, the step of forming the nanowire growth layer includes depositing a conductive compound on the back electrode layer, depositing at least one of gold (Au), platinum (Pt), silver (Ag), and palladium (Pd) And forming a catalytic particle layer made of a metal catalyst containing the metal catalyst.

In an embodiment, the step of forming the photoelectric conversion layer comprises depositing a dielectric to surround the n-type III-V compound nanowire, and depositing a dielectric to surround the p-type III-V compound nanowire Step < / RTI >

In an embodiment, the step of forming the transparent electrode layer may include the step of depositing a conductive compound on the photo-conversion layer so as to be connected to the top of the p-type III-V compound nano-wire.

In a specific example, the step of forming the photoelectric conversion layer and the step of forming the transparent electrode layer may be repeated two or more times so that the unit including the photoelectric conversion layer and the transparent electrode layer may be laminated.

In a specific example, a metal catalyst containing at least one of gold (Au), platinum (Pt), silver (Ag), and palladium (Pd) is formed on a transparent electrode layer in which the unit including the photoelectric conversion layer and the transparent electrode layer are laminated The catalyst particle layer made may be further laminated.

In one embodiment, a dielectric layer is formed on the transparent electrode layer to form a dielectric layer, and the step of forming the nanowire growth layer, the step of forming the photoelectric conversion layer, and the step of forming the transparent electrode layer may be repeated one or more times Repeatedly, a unit composed of a dielectric layer, a nanowire growth layer, a photoelectric conversion layer, and a transparent electrode layer can be further stacked.

The present invention uses a III-V group compound having a nano wire structure in the photoelectric conversion layer to enable lamination, has a wide band gap range, can exhibit high performance and high efficiency, V group compound solar cell using a small amount of III-V group compound and a method for producing the same. In particular, the stacked nanowire structure of the III-V compound solar cell according to the present invention is also useful as a photo detector.

1 is a cross-sectional view of a III-V compound solar cell according to an embodiment of the present invention.
2 is a cross-sectional view of a stacked III-V compound solar cell according to another embodiment of the present invention.
3 is a cross-sectional view of a stacked III-V compound solar cell according to another embodiment of the present invention in which electrodes for each layer are separated.
Figure 4 is a scanning electron microscope (SEM) photograph of n-type III-V compound nanowires formed according to one embodiment of the present invention.
5 is a graph showing the lattice constants and energy bandgaps of the solar spectrum and III-V compounds.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

1 is a cross-sectional view (schematic) of a III-V compound solar cell according to an embodiment of the present invention. As shown in FIG. 1, a III-V compound solar cell according to the present invention is a substrate 10. A back electrode layer 20 formed on the substrate 10, a nanowire growth layer 30 formed on the back electrode layer 20, a photoelectric conversion layer 40 formed on the nanowire growth layer 30, ) And a transparent electrode layer (50) formed on the photoelectric conversion layer (40).

As the substrate 10 used in the present invention, an ordinary solar cell substrate can be used, and glass or a flexible substrate can be used for cost reduction. For example, as the flexible substrate, an insulating material such as plastic, which has light transmittance and is applicable at a high temperature, may be used. The thickness of the substrate 10 may be, for example, 10 to 300 占 퐉, but is not limited thereto.

The back electrode layer 20 used in the present invention is formed on the substrate 10. Since the solar cell of the present invention is manufactured at a high temperature of 400 to 650 ° C, it is preferable that the solar cell is made of a material that can withstand high temperatures. The back electrode layer 20 may be formed by depositing one or more metals such as molybdenum (Mo), tungsten (W), nickel (Ni), and copper (Cu) . It is preferable that the back electrode layer 20 has low resistivity as an electrode and is excellent in adhesiveness to the substrate 10 and does not cause peeling due to a difference in thermal expansion coefficient. The thickness of the back electrode layer 20 may be, for example, 1 to 100 탆, but is not limited thereto.

The nanowire growth layer 30 used in the present invention includes a conductive compound layer formed by depositing a conductive compound on the back electrode layer 20 and a conductive compound layer formed on the conductive compound layer using gold (Au), platinum (Pt), silver (Ag) (NW) growth method using a catalyst, which comprises a catalyst particle layer composed of at least one metal catalyst such as palladium (Pd), preferably a gold catalyst, -V compound nanowires 42 and p-type III-V compound nanowires 44. The nanowires 42 can be grown in the following manner. The n-type III-V compound nanowire 42 may be formed (grown) between the catalyst particles of the catalyst particle layer and the conductive compound layer, and the p-type III- May be formed between catalyst particles of the catalytic particle layer and the top of the n-type III-V compound nanowire (42).

Examples of the conductive compound include a group III-V compound and zinc oxide (ZnO) doped with aluminum (Al), ITO, graphine, carbon nano tube, and the like having low ohmic resistance (ZnO), zinc (O) doped with aluminum (Al), or a combination thereof may be used.

The catalyst particle diameter of the catalyst particle layer may be 1 to 100 nm, preferably 5 to 40 nm, more preferably 10 to 30 nm. In this range, the group III-V compound is injected between the catalyst particles having a relatively low melting point and the conductive compound layer (or the n-type III-V compound nanowire 42) Growing n-type and p-type III-V compound nanowires 42 and 44 can be obtained.

The thickness of the nanowire growth layer 30 is, for example, 1 to 20 占 퐉, preferably 2 to 10 占 퐉. In the above range, the efficiency of photoelectric conversion with respect to the length of the nanowires 42 and 44 is excellent.

The photoelectric conversion layer 40 used in the present invention is formed by forming an n-type III-V compound nanowire 42 formed below the metal catalyst (catalyst particle) on the nanowire growth layer 30, the n-type III- Type compound nanowire 42 formed below the metal catalyst (catalyst particle) following the nanowire nanowire 42. The p-type III- The photoelectric conversion layer 40 is formed on the dielectric 40 surrounding the n-type III-V compound nanowire 42 and the p-type III-V compound nanowire 44 (except for 42 and 44) . ≪ / RTI >

Since the photoelectric conversion layer 40 uses a III-V group compound having a nano wire structure, the amount of the source (III-V group compound) used can be reduced by about 1/10 as compared with the thin film type, The conventional III-V compound nanowire structure is a structure capable of only a single junction, but the III-V compound nanowire structure of the present invention is a structure capable of being laminated. In the case of the thin film type, since the lattice structure should be similar to that of GaAs used as the substrate, only the photoelectric conversion layer having the energy band gap width of about 1.3 to 1.9 eV can be formed. In the case of the nanowire structure according to the present invention, A material having a lattice structure similar to that of a material having a larger lattice structure than that of a material having a lattice structure can be formed with a one-dimensional growth free from lateral strain, and thus the energy band gap width can be widened to 0.3 to 2.1 eV.

The n-type III-V compound nanowire 42 and the p-type III-V compound nanowire 44 are n and p-type In _xy Ga _{(1-x) y} Al _{1- y} As _z P _{1 - z (0≤x≤1, 0≤y≤1, 0≤z≤1)} , InGaAs, or may be a combination thereof, preferably may be formed from the n-InGaAs and p-InGaAs, respectively. The n-type III-V compound nanowire 42 and the p-type III-V compound nanowire 44 form a pn junction and can generate electromotive force (photovoltage) when sunlight is incident will be. The diameter of each of the n-type and p-type III-V compound nanowires 42 and 44 is 1 to 100 nm, preferably 5 to 40 nm, more preferably 10 to 30 nm, and the length is 1 to 20 μm , Preferably 2 to 15 mu m, and more preferably 3 to 10 mu m. Within this range, crystal structure formation (nanowire formation) is possible by one-dimensional growth free from lateral strain, and the efficiency of photoelectric conversion to nanowire lengths 42 and 44 is excellent.

The dielectric is formed by passivating the n and p-type III-V compound nanowires 42 and 44 and isolating the n-type III-V compound nanowires 42 ) And the p-type III-V compound nanowire 44 are deposited. As the dielectric material, for example, a dielectric material such as SiO ₂ or SiNx which can be grown at a high temperature can be used.

The thickness of the photoelectric conversion layer 40 is 2 to 40 mu m, preferably 4 to 30 mu m, more preferably 6 to 20 mu m. Within this range, crystal structure formation (nanowire formation) is possible by one-dimensional growth free from lateral strain, and the efficiency of photoelectric conversion to nanowire lengths 42 and 44 is excellent. In addition, the energy band gap range of the photoelectric conversion layer 40 may be 0.3 to 2.1 eV.

The transparent electrode layer 50 used in the present invention is obtained by depositing a conductive compound on the photoelectric conversion layer 40 so as to be connected to the top of the p-type III-V compound nanowire 44, Which is excellent in light transmittance and electrical conductivity.

As the conductive compound, a conductive compound used in the conductive compound layer may be used. For example, zinc oxide (ZnO), aluminum (Al) -doped zinc oxide having low ohmic resistance and Group III- (ZnO), zinc (O) doped with aluminum (Al), and a combination thereof, may be used in combination with a metal oxide such as ITO, graphine, carbon nanotube, Can be used. Particularly, the zinc oxide has an energy band gap of about 3.37 eV, has a high light transmittance of 80% or more, and can be doped with aluminum or the like to obtain a low resistance value of 10 ^-4 Ω · cm or less. Further, if necessary, it may be doped with a boron atom (B) to increase the shortcircuit current. The thickness of the transparent electrode layer 50 is, for example, preferably 1 to 20 占 퐉, preferably 2 to 10 占 퐉. Within this range, conductivity and transparency can be excellent.

As shown in FIG. 1, an electrode pad 60 for collecting current on the surface of a solar cell is formed on the back electrode layer 20 and the transparent electrode layer 50 in the III-V compound solar cell of the present invention . The electrode pad 60 can be formed by, for example, depositing aluminum (Al), nickel (Ni), a combination thereof, and the like in a predetermined pattern.

2 is a cross-sectional view (schematic diagram) of a stacked III-V compound solar cell according to another embodiment of the present invention. 2, a group III-V compound solar cell according to the present invention is characterized in that the unit consisting of the photoelectric conversion layer 40 and the transparent electrode layer 50 is at least two times, preferably three to fifteen times, And the transparent electrode layer (50, 50a, 50b, 50c) on which the unit is laminated, the catalyst particle layer is further laminated on the transparent electrode layer (50, 50a, 50b, 50c) And the photoelectric conversion layers 40, 40a, 40b, 40c, and 40d may be a stacked III-V compound solar cell having a larger energy bandgap away from the substrate. The solar cell of the present invention is characterized in that the energy band gap of each photoelectric conversion layer (40, 40a, 40b, 40c, 40d) is adjusted by controlling the ratio of the group III compound and the group V compound by using the catalyst particle layer as a seed And a nanowire having a larger energy bandgap as the distance from the substrate is stacked, so that the stacked III-V compound solar cell can be formed.

The stacked type solar cell has p-type III-V compound nanowires 44, 44a, 44b, and 44c as a boundary between the transparent electrode layers 50, 50a, 50b, the n-type III-V compound nanowires 42a, 42b, 42c, and 42d exist in a high concentration and tunneling is performed through the transparent electrode layers 50, 50a, 50b, and 50c. That is, in the stacked III-V compound solar cell, the transparent electrode layers 50, 50a, 50b and 50c serve as a tunnel junction, and the electrode pads 60 serve as the back electrode layer 20 and the uppermost electrode layer. On the transparent electrode layer 50d. The energy bandgaps of the photoelectric conversion layers 40a, 40b, 40c and 40d are 0.7 eV (40), 1.0 eV (40a), 1.2 eV (40b), 1.4 eV (40c) And 1.8 eV (40d).

FIG. 3 is a cross-sectional view (schematic diagram) of a stacked III-V compound solar cell in which electrodes for each layer are separated according to another embodiment of the present invention. 3, the III-V compound solar cell according to the present invention includes dielectric layers 70a, 70b, 70c, and 70d, nanowire growth layers 30a, 30b, 30c, The unit consisting of the photoelectric conversion layers 40a, 40b, 40c and 40d and the transparent electrode layers 50a, 50b, 50c and 50d is repeated one or more times and further laminated The stacked photoelectric conversion layers 40, 40a, 40b, 40c, and 40d may be a stacked III-V compound solar cell having an energy bandgap separated from the respective layers as the layers are separated from the substrate.

In the stacked III-V compound solar cell in which the electrodes for each layer are separated, each unit (layer) including the photoelectric conversion layers 40, 40a, 40b, 40c and 40d is formed of dielectric layers 70a, 70b, 70c and 70d And the electrode pad 60 is formed on the back electrode layer 20 and each of the transparent electrode layers 50, 50a, 50b, 50c, and 50d. The power generated from the solar cell is obtained by adding power obtained by each unit. The energy bandgaps of the photoelectric conversion layers 40, 40a, 40b, 40c and 40d are 0.7 eV (40), 1.0 eV (40a), 1.2 eV (40b), 1.4 eV eV 40d, and the thickness of the dielectric layers 70a, 70b, 70c, and 70d may be, for example, 0.01 to 2 占 퐉, but is not limited thereto.

The III-V compound solar cell according to the present invention can be used not only as a solar cell but also as a semiconductor element such as a light receiving element. For example, when a stacked III-V compound solar cell in which the electrodes for each layer are separated is used as a light receiving element, signals can be obtained for each unit (layer).

Another aspect of the present invention relates to a method for producing the III-V compound solar cell. A method for fabricating a III-V compound solar cell according to the present invention comprises the steps of: forming a nanowire growth layer (30) on a substrate (10) on which a back electrode layer (20) is formed; An n-type III-V compound is grown on the nanowire growth layer 30 to form an n-type III-V compound nanowire 42 and an n-type III-V compound nanowire 42 to form a p-type III-V compound nanowire 44 to form a photoelectric conversion layer 40; And forming a transparent electrode layer (50) on the photoelectric conversion layer (40).

The method for manufacturing a III-V compound solar cell may further include depositing aluminum (Al), nickel (Ni), a combination thereof, and the like in a predetermined pattern on the back electrode layer 20 and the transparent electrode layer 50 Thereby forming an electrode pad 60. [0050]

The step of forming the nanowire growth layer 30 may include depositing the conductive compound on the back electrode layer 20 and depositing the conductive compound on the back electrode layer 20 using gold (Au), platinum (Pt), silver (Ag) ), And palladium (Pd) on the surface of the catalytic particle layer.

The conductive compound may be deposited by a conventional deposition method, for example, at a deposition temperature of 25 to 200 DEG C, preferably 30 to 100 DEG C, a deposition time of 1 to 120 minutes, preferably 5 to 30 minutes Lt; / RTI > Within this range, a good thin film (conductive compound layer) can be formed.

The catalyst particle layer may be formed by, for example, applying a colloidal solution of the metal catalyst on the back electrode layer 20 and then blowing with a nitrogen gas (N ₂ gun) for 10 to 60 seconds, for example, , But it is not limited as long as it can form a particle layer.

In an embodiment, the step of forming the transparent electrode layer may include the step of depositing a conductive compound on the photo-conversion layer so as to be connected to the top of the p-type III-V compound nano-wire.

In the step of forming the photoelectric conversion layer 30, the n-type III-V compound may be grown using a conventional metal catalyst, for example, a metalorganic chemical vapor deposition type III-V group compound (III-V compound) at a deposition temperature of 350 to 650 占 폚, preferably 400 to 600 占 폚, and a deposition time of 0.1 to 30 minutes, preferably 0.5 to 10 minutes, The nanowire 42 may be grown (deposited) on the nanowire growth layer 30 under the metal catalyst particles. Within this range, the nanowire 42 having a sufficient diameter and length can be obtained, which is advantageous for crystal structure formation by one-dimensional growth free from strain.

The n-type III-V compound nanowire 42 may be doped with an n-type dopant and the doping may be performed using an n-type III-V compound nanowire 42 when forming the n-type III- A dopant such as silicon (Si), tellurium (Te), or selenium (Se) source gas may be added to the nanowire 42 when the nanowire 42 is grown, or after the nanowire 42 is grown, The source gas may be diffused, but the present invention is not limited thereto.

The p-type III-V compound may also be grown using the same method as the n-type III-V compound growth method, for example, by metalorganic chemical vapor deposition (MOCVD) Type III-V compound nanowire 42 at a deposition temperature of 350 to 650 ° C, preferably 400 to 600 ° C, and a deposition time of 0.1 to 30 minutes, preferably 0.5 to 10 minutes. The nanowire 44 may be grown below the metal catalyst particles. Within this range, the nanowire 44 having a sufficient diameter and length can be obtained, which is advantageous for crystal structure formation by one-dimensional growth free from strain.

The p-type III-V compound nanowire 44 may be doped with a p-type dopant, and the doping may be performed by forming p-type III- A source gas such as carbon (C) or zinc (Zn), which is a dopant, may be added to the nano wire 44 when the nano wire 44 is grown, or after the nano wire 44 is grown, However, the present invention is not limited thereto.

The step of forming the photoelectric conversion layer 30 includes depositing a dielectric to surround the n-type III-V compound nanowire 42 and surrounding the p-type III-V compound nanowire 44 The n and p-type III-V compound nanowires 42 and 44 may be passivated and separated from and contacted with each electrode layer. After the step of depositing a dielectric to surround the n-type and p-type III-V compound nanowires 42 and 44, the top of the n-type and p-type III-V compound nanowires 42 and 44 (For example, removing a dielectric layer of about 0.1 mu m in thickness) by etching the upper portion of the formed dielectric layer to expose the dielectric layer.

In the manufacturing method of the present invention, the dielectric may be deposited by a conventional deposition method. For example, a dielectric material such as SiO ₂ or SiNx may be deposited by a plasma enhanced chemical vapor deposition (PECVD) At a temperature of 25 to 350 DEG C, preferably 30 to 300 DEG C, and a deposition time of 1 to 120 minutes, preferably 5 to 30 minutes. Within the above range, the dielectric material can be deposited without affecting the physical properties of the photoelectric conversion layer 30.

The method for fabricating a III-V compound solar cell according to the present invention is characterized in that the step of forming the photoelectric conversion layer 40 and the step of forming the transparent electrode layer 50 are repeated two or more times to form the photoelectric conversion layer 40, By stacking the unit of the transparent electrode layer 50, a stacked III-V compound solar cell can be manufactured. Here, the catalyst particle layer is deposited on the transparent electrode layers 50, 50a, 50b and 50c on which the unit consisting of the photoelectric conversion layer 40 and the transparent electrode layer 50 are laminated, and n-type III-V Group compound nanowires 42a, 42b, 42c, and 42d can be grown.

The method for fabricating a laminated III-V compound solar cell may further include the step of forming a layered III-V compound solar cell on the back electrode layer 20 and the uppermost transparent electrode layer 50d, To form an electrode pad 60. The electrode pad 60 may be formed by depositing the electrode pad 60 in a pattern.

The method for fabricating a III-V compound solar cell of the present invention includes the steps of forming a dielectric layer 70a by depositing a dielectric material on the transparent electrode layer 50 and forming the nanowire growth layer 30, The step of forming the photoelectric conversion layer 40 and the step of forming the transparent electrode layer 50 are repeated one or more times to form the dielectric layers 70a, 70b, 70c and 70d, the nanowire growth layers 30a, 30b and 30c , The photoelectric conversion layers 40a, 40b, 40c, and 40d, and the transparent electrode layers 50a, 50b, 50c, and 50d are further stacked to form the stacked III- A battery can be manufactured.

The method for manufacturing a laminated III-V compound solar cell in which the electrodes for each of the layers are separated is characterized in that the method for manufacturing a laminated III-V compound solar cell comprises the steps of: forming a metal layer on the back electrode layer 20 and each of the transparent electrode layers 50, 50a, 50b, 50c, (Al), nickel (Ni), a combination thereof, and the like in a predetermined pattern to form the electrode pad 60.

Hereinafter, the present invention will be described in more detail by way of examples, but these examples are for illustrative purposes only and should not be construed as limiting the present invention.

Example

Example  One

A method of manufacturing a III-V compound solar cell according to an embodiment of the present invention will be described in more detail as follows.

First, molybdenum (Mo) or the like is deposited on the glass or flexible substrate 10 to form the rear electrode layer 20, and zinc oxide doped with zinc oxide (ZnO) or aluminum (Al) is deposited. The resultant was immersed in PLL (poly-L-lysine) solution for 3 minutes, washed with deionized water, and dried with nitrogen (N ₂ ). A gold (Au) colloid solution having a diameter of 20 nm was coated on the dried product and blown with a nitrogen (N ₂ ) gun for 30 seconds to form a catalyst particle layer. Then, a metalorganic chemical vapor deposition (MOCVD) (H ₂ ) was flowed at 620 ° C. for 15 minutes to remove surface contamination to form a nanowire growth layer (Au / ZnO alloy) 30 in which a gold catalyst particle layer was formed. Next, the temperature of the evaporator was lowered to 470 캜, and n-InGaAs nanowires (NW) were grown by growing at least 2 탆 of n-InGaAs as an n-type III- / RTI > In order to deposit SiO ₂ as a dielectric on the n-InGaAs nanowire 42 and deposit (grow) p-InGaAs on the n-InGaAs nanowire 42 as a p-type III-V compound, BOE InGaAs nanowire 42 exposed on the SiO ₂ layer at 470 캜 is etched by about 0.1 탆 about the SiO ₂ layer deposited with the oxide catalyst or the hydrogen fluoride (HF) solution, P-InGaAs nanowire 44 was formed by growing p-InGaAs at a thickness of 2 탆 or more. SiO ₂ is deposited as a dielectric material on the formed p-InGaAs nanowire 44 to form the photoelectric conversion layer 40 and then the SiO ₂ deposited as described above, including the upper end of the p-InGaAs nanowire 44, Layer was etched by about 0.1 탆 and zinc oxide doped with zinc oxide (ZnO) or aluminum (Al) was deposited to form a transparent electrode layer 50. Next, aluminum (Al) is deposited in a predetermined pattern on the back electrode layer 20 and the transparent electrode layer 50 to form an electrode pad 60, and a III-V compound solar cell shown in FIG. 1 is manufactured Respectively. Scanning electron microscope (SEM) photographs of the top surface and cross section of the n-type III-V compound (n-InGaAs) nanowire are shown in FIG.

Example  2

A method for manufacturing a stacked III-V compound solar cell according to another embodiment of the present invention will be described in more detail as follows.

In the method of manufacturing a III-V compound solar cell according to an embodiment of the present invention, the step of forming the photoelectric conversion layer 40 and the step of forming the transparent electrode layer 50 are repeated five times, Layers 40a, 40b, 40c, and 40d and transparent electrode layers 50a, 50b, 50c, and 50d were formed. The n-type III-V compound nanowires 42a, 42b, 42c and 42d are grown on gold (Au) by depositing the gold colloid solution on the transparent electrode layers 50, 50a, 50b and 50c . Next, aluminum (Al) is deposited in a predetermined pattern on the back electrode layer 20 and the uppermost transparent electrode layer 50d to form an electrode pad 60, and the laminate III-V compound solar cell shown in FIG. A battery was prepared.

Example  3

A method for manufacturing a stacked III-V compound solar cell in which electrodes for each layer are separated according to another embodiment of the present invention will be described in more detail as follows.

In the method of manufacturing a III-V compound solar cell according to an embodiment of the present invention, a dielectric is deposited on the transparent electrode layer 50 to form a dielectric layer 70a, and the nanowire growth layer 30 is formed The steps of forming the photoelectric conversion layer 40 and forming the transparent electrode layer 50 are repeated four times to form the dielectric layers 70a, 70b, 70c and 70d, the nanowire growth layers 30a and 30b , 30c, and 30d, photoelectric conversion layers 40a, 40b, 40c, and 40d, and transparent electrode layers 50a, 50b, 50c, and 50d. Next, aluminum (Al) is deposited in a predetermined pattern on the back electrode layer 20 and the respective transparent electrode layers 50, 50a, 50b, 50c and 50d to form electrode pads 60, Layer type III-V compound solar cell was prepared.

It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims (20)

Board;
A back electrode layer formed on the substrate;
A nanowire growth layer formed on the back electrode layer;
A photoelectric conversion layer formed on the nanowire growth layer; And
And a transparent electrode layer formed on the photoelectric conversion layer,
Wherein the photoelectric conversion layer comprises an n-type III-V compound nano wire (NW) formed on the nanowire growth layer, and a p-type III-V layer formed on the n-type III- Group III compound semiconductor nanowire and a dielectric surrounding the n-type III-V compound nanowire and the p-type III-V compound nanowire.
The nanowire growth layer according to claim 1, wherein the nanowire growth layer comprises a conductive compound layer formed by depositing a conductive compound on the back electrode layer, and a conductive compound layer formed on the conductive compound layer by using gold (Au), platinum (Pt), silver (Ag) Lt; RTI ID = 0.0 > III-V < / RTI > compound solar cell.
3. The Group III-V compound according to claim 2, wherein the conductive compound comprises at least one of zinc oxide (ZnO), zinc oxide doped with aluminum (Al), ITO, graphene, Solar cells.
3. The III-V compound solar cell according to claim 2, wherein the n-type III-V compound nanowire is formed between the catalyst particles of the catalyst particle layer and the conductive compound layer.
The III-V compound solar cell according to claim 1, wherein the transparent electrode layer is formed by depositing a conductive compound on the photoelectric conversion layer so as to be connected to an upper end of the p-type III-V compound nanowire.
delete The III-V compound solar cell of claim 1, wherein the substrate is a glass or a flexible substrate.
The III-V compound solar cell according to claim 1, wherein the back electrode layer is made of a metal containing at least one of molybdenum (Mo), tungsten (W), nickel (Ni), and copper (Cu) .
2. The compound according to claim 1, wherein the n and p-type III-V compound nanowires are n and p-type In _xy Ga _{(1-x) y} Al _{1 -y} As _z P _{1 -z} 0? Y? 1, 0? Z? 1), InGaAs, or a combination thereof.
2. The III-V compound solar cell according to claim 1, wherein the n and p-type III-V compound nanowires have a diameter of 1 to 100 nm and a length of 1 to 20 m.
The III-V compound solar cell according to claim 1, wherein the energy band gap range of the photoelectric conversion layer is 0.3 to 2.1 eV.
The method according to claim 1, wherein the unit including the photoelectric conversion layer and the transparent electrode layer is repeated twice or more, and gold (Au), platinum (Pt), silver (Ag) Wherein a catalyst particle layer made of a metal catalyst containing at least one palladium (Pd) is further laminated, and a photoelectric conversion layer stacked has a larger energy bandgap as it is away from the substrate.
3. The method according to claim 1, wherein a unit consisting of a dielectric layer, a nanowire growth layer, a photoelectric conversion layer, and a transparent electrode layer is repeated one or more times on the transparent electrode layer, and the photoelectric conversion layer Lt; RTI ID = 0.0 > III-V < / RTI > compound solar cell.
Forming a nanowire growth layer on a substrate on which a back electrode layer is formed;
Growing an n-type III-V compound on the nanowire growth layer to form an n-type III-V compound nano wire and forming a p-type III-V compound on the n-type III- Group compound to form a p-type III-V compound nanowire to form a photoelectric conversion layer; And
And forming a transparent electrode layer on the photoelectric conversion layer,
The step of forming the photoelectric conversion layer includes depositing a dielectric to surround the n-type III-V compound nanowire, and depositing a dielectric to surround the p-type III-V compound nanowire Lt; RTI ID = 0.0 > III-V < / RTI > compound solar cell.
15. The method of claim 14, wherein forming the nanowire growth layer comprises: depositing a conductive compound on the back electrode layer; depositing gold (Au), platinum (Pt), silver (Ag), and palladium And forming a catalytic particle layer made of a metal catalyst containing at least one kind of metal catalyst.
delete 15. The method of claim 14, wherein the step of forming the transparent electrode layer is a step of depositing a conductive compound on the photoelectric conversion layer so as to be connected to an upper end of the p-type III-V compound nanowire. ≪ / RTI >
15. The method according to claim 14, wherein the step of forming the photoelectric conversion layer and the step of forming the transparent electrode layer are repeated two or more times so that the unit comprising the photoelectric conversion layer and the transparent electrode layer is laminated. V compound solar cell.
The method according to claim 18, wherein a transparent electrode layer on which the unit consisting of the photoelectric conversion layer and the transparent electrode layer is laminated is formed of a metal containing at least one of gold (Au), platinum (Pt), silver (Ag), and palladium (Pd) Lt; RTI ID = 0.0 > III-V < / RTI > compound solar cell.
15. The method of claim 14, further comprising: forming a dielectric layer by depositing a dielectric on the transparent electrode layer; forming the nanowire growth layer; forming the photoelectric conversion layer; and forming the transparent electrode layer So that a unit composed of a dielectric layer, a nanowire growth layer, a photoelectric conversion layer, and a transparent electrode layer is further laminated on the surface of the III-V compound solar cell.

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