KR102165004B1 - A photovoltaic particle unit and a transparent solar battery with the unit - Google Patents

Abstract

The particle unit for photovoltaic power generation of the present invention includes a base particle, a thin oxide layer formed outside the base particle, a diffusion layer formed outside the thin oxide layer, and a transparent conductive layer formed outside the diffusion layer. In addition to this, a high concentration layer formed outside the diffusion layer may be further included, or an antireflection-passivation layer formed outside the diffusion layer may be further included. Therefore, it is possible to prevent the recombination of the P-N junction of the photovoltaic particle unit, thereby improving photovoltaic efficiency.

Description

A particle unit for photovoltaic power generation and a transparent solar cell including the same {A PHOTOVOLTAIC PARTICLE UNIT AND A TRANSPARENT SOLAR BATTERY WITH THE UNIT}

The present invention relates to a particle unit for photovoltaic power generation and a transparent solar cell including the same.

Solar cells using silicon balls are being developed in conventional panel-type solar cells. However, the technology to increase the efficiency of the silicon ball itself has not been developed yet.

In manufacturing a solar cell using silicon balls, various manufacturing methods have been developed, but further research on a method capable of having power productivity and cost competitiveness of other solar panels is required.

In solar cells, the efficiency of power generation is one of the most important factors, and various methods of increasing power production efficiency under the same structure are required.

Korean Patent Registration No. 10-1325572

The present invention is to solve the above problems, to provide a particle unit for photovoltaic power generation capable of increasing the efficiency of self-power generation, and a transparent solar cell including the same.

To solve these problems, the particle unit for photovoltaic power generation provided by the present invention includes a base particle, a thin oxide layer formed outside the base particle, a diffusion layer formed outside the thin oxide layer, and a transparent conductive layer formed outside the diffusion layer. do.

In one embodiment, a high concentration layer formed outside the diffusion layer may be further included.

In one embodiment, an anti-reflection-passivation layer formed outside the diffusion layer may be further included.

In one embodiment, the base particle may be a doped silicon ball.

In one embodiment, the thin oxide layer may have a thickness of 0.5 to 20 nm.

In one embodiment, the diffusion layer may be a polysilicon layer having a thickness of 5 to 2000 nm.

In one embodiment, the high concentration layer may be an amorphous silicon layer doped with a high copper furnace with impurities of the same series as the diffusion layer.

In one embodiment, the anti-reflection-passivation layer may include an opening to electrically connect the diffusion layer and the transparent conductive layer therein.

In addition, in order to solve the present problem, the transparent solar cell using the particle unit for photovoltaic power generation provided by the present invention is a transparent solar cell including a plurality of photovoltaic particle units, a plurality of lower electrodes, a plurality of upper electrodes, and an insulating layer. The photovoltaic particle unit includes a partially exposed base particle, a thin oxide layer formed outside the base particle, a diffusion layer formed outside the thin oxide layer, and a transparent conductive layer formed outside the diffusion layer. In addition, one end of the plurality of lower electrodes is electrically connected to the exposed particles of the photovoltaic particle unit, and the other ends of the plurality of lower electrodes are electrically connected to one end of the plurality of upper electrodes, respectively, and a plurality of The other end of the upper electrode is electrically connected to the transparent conductive layer of the photovoltaic particle unit, and the insulating layer is formed between the plurality of lower electrodes and the diffusion layer and the transparent conductive layer of the particle unit.

In one embodiment, it may be characterized in that it further comprises an optically transparent layer surrounding the plurality of photovoltaic particle units.

In one embodiment, the insulating layer may be formed by being divided into a plurality, and may be formed only around the base particles of each of the photovoltaic particle units.

In one embodiment, each of the photovoltaic particle units may further include a high concentration layer formed outside the diffusion layer.

In one embodiment, each of the photovoltaic particle units may further include an anti-reflection-passivation layer formed outside the diffusion layer.

In an embodiment, the anti-reflection-passivation layer of each of the photovoltaic particle units may include an opening to electrically connect the diffusion layer and the transparent conductive layer therein.

According to the present invention as described above, as each layer has a structure for improving the recombination structure in the PN junction, it is possible to manufacture a solar cell with improved efficiency compared to the conventional method.

In addition, since the metal electrode and bulk silicon are not in direct contact, surface recombination can be prevented, and since the dpoed poly layer is in total contact with the transparent metal electrode, the fill factor can be improved. This improved solar cell can be manufactured.

In addition, since the open-circuit voltage can be improved due to the role of the high concentration layer, it is possible to manufacture a solar cell with improved efficiency compared to the conventional method.

1A is a cross-sectional view showing a particle unit for photovoltaic power generation according to an embodiment of the present invention.
1B is a cross-sectional view showing an electrode formed in the particle unit for photovoltaic power generation according to the embodiment of FIG. 1A.
2A is a cross-sectional view showing a particle unit for photovoltaic power generation according to another embodiment of the present invention.
2B is a cross-sectional view showing an electrode formed in the particle unit for photovoltaic power generation according to the embodiment of FIG. 2A.
3A is a cross-sectional view showing a particle unit for photovoltaic power generation according to another embodiment of the present invention.
3B is a cross-sectional view showing an electrode formed in the particle unit for photovoltaic power generation according to the embodiment of FIG. 3A.

Hereinafter, exemplary embodiments disclosed in the present specification will be described in detail with reference to the accompanying drawings, but identical or similar elements are denoted by the same reference numerals regardless of reference numerals, and redundant descriptions thereof will be omitted. The suffixes "module" and "unit" for components used in the following description are given or used interchangeably in consideration of only the ease of preparation of the specification, and do not have meanings or roles that are distinguished from each other by themselves. In addition, in describing the embodiments disclosed in the present specification, when it is determined that a detailed description of related known technologies may obscure the subject matter of the embodiments disclosed herein, the detailed description thereof will be omitted. In addition, the accompanying drawings are for easy understanding of the embodiments disclosed in the present specification, and the technical idea disclosed in the present specification is not limited by the accompanying drawings, and all modifications included in the spirit and scope of the present invention It should be understood to include equivalents or substitutes.

When a component is referred to as being "connected" or "connected" to another component, it is understood that it may be directly connected or connected to the other component, but other components may exist in the middle. Should be. On the other hand, when a component is referred to as being "directly connected" or "directly connected" to another component, it should be understood that there is no other component in the middle.

Singular expressions include plural expressions unless the context clearly indicates otherwise.

In addition, throughout the specification of the present application, when a certain part "includes" a certain component, it means that other components may be further included rather than excluding other components unless otherwise stated.

It is apparent to those skilled in the art that the present invention may be embodied in other specific forms without departing from the essential features of the present invention.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the drawings. In the drawings, the same reference numerals refer to the same elements.

First embodiment of the silicon particle unit

1A is a cross-sectional view showing a particle unit for photovoltaic power generation according to an embodiment of the present invention.

Referring to FIG. 1A, the photovoltaic particle unit 100a includes a base particle 110, a thin oxide layer 120 formed outside the base particle 110, a diffusion layer 130 formed outside the thin oxide layer 120, It includes a transparent conductive layer 160 formed outside the diffusion layer 130.

The base particle 110 may be formed of silicon. The base particle 110 may be formed in a silicon ball doped with a P-type or N-type dopant. Alternatively, it may be formed of P-type or N-type silicon.

The base particle 110 itself may have a structure formed of silicon and may have a structure in which silicon is coated on an insulating ball. The insulating ball may be made of various materials such as glass and ceramic. The base particle 110 may be manufactured not only in a ball shape, but also in a polyhedral shape. The shape of the polyhedron includes a cubic structure.

A thin oxide layer 120 is formed outside the base particle 110, and a diffusion layer 130 is formed outside the thin oxide layer 120. The diffusion layer 130 will be described first. As described, the base particle 110 includes P-type or N-type silicon, and a diffusion layer 130 forming a P-N junction is formed outside the base particle 110. By this P-N junction, it is possible to generate electric energy by receiving light energy.

The diffusion layer 130 may be formed of polysilicon by annealing a layer of boron or phosphorus doped a-Si. The annealing process may use thermal annealing, laser annealing, or E-beam annealing. Alternatively, low pressure chemical vapor deposition (LPCVD) may be used to form a polysilicon layer doped with boron or phosphorus. The thickness of the diffusion layer 130 is formed within about 5 nm to 2000 nm.

Alternatively, the PN junction can be spiritualized by injecting Boron or Phosphorous in various methods such as a solution containing dopant, Sol, Gel, or implant into the a-Si or polySi layer without impurities.

The thin oxide layer 120 is positioned between the P-N junction formed by the base particle 110 and the diffusion layer 130 in this way. The thin film oxide layer 120 reduces internal recombination that may occur in a single P-N junction in a P-N junction. The thin film oxide layer 120 may be formed of a metal oxide such as AlOx, SiOx, SiONx, or TiOx, or a dielectric layer.

The thickness of the thin film oxide layer 120 is formed as thin as about 0.5 to 20 nm. If it is formed with a certain thickness or more, it may interfere with the formation of the P-N junction, so it must be formed as a thin film.

The transparent conductive layer 160 may be coated in the process of forming the base particle 110. On the one hand, after the base particle 110 is mounted on a substrate or electrode, it may be coated in a manufacturing process. Since the transparent conductive layer 160 does not directly contact the base particle 110, contact with the bulk silicon is not generated. Accordingly, recombination on the surface does not occur, and since it has electrical conductivity, when the upper electrode contacts only the transparent conductive layer 160, the electrode is electrically connected to improve contact resistance. At the same time, since there is no need to remove a part of the transparent conductive layer 160 in order to expose the diffusion layer 130, an advantage acts on the process.

The transparent conductive layer 160 may be formed of a transparent conductive oxide (TCO) such as FTO, AZO, and ITO. The thickness of the transparent conductive layer 160 may be approximately 10 nm to 500 nm.

Accordingly, in the particle unit 100a for photovoltaic power generation according to the present embodiment, the open-circuit voltage (Voc), which is the maximum possible voltage, may be improved, and thus, the fill factor (FF) may be improved.

1B is a cross-sectional view showing an electrode formed in the particle unit for photovoltaic power generation according to the embodiment of FIG. 1A.

Referring to FIG. 1B, an upper electrode 200, a lower electrode 300, and an insulating layer 400 are formed on the particle unit 100a for photovoltaic power generation according to the embodiment of FIG. 1A. A plurality of units as shown in FIG. 1B are formed to form one solar cell.

One photovoltaic particle unit 100a is processed to expose the base particle 110 so that it can be electrically connected. At this time, in order to expose the base particles 110, portions of the thin oxide layer 120, the diffusion layer 130, and the transparent conductive layer 160 are respectively removed. Accordingly, the base particle 110 is exposed on one side of the photovoltaic particle unit 100a, and cross-sections of the thin film oxide layer 120, the diffusion layer 130, and the transparent conductive layer 160 are exposed.

One end of the lower electrode 300 is electrically connected to the exposed base particle 110 to form one electrode of the photovoltaic power plant formed of a P-N junction. In addition, one end of the upper electrode 200 is electrically connected to the transparent conductive layer 160 to form another electrode of the optical power plant. The other end of one upper electrode 200 and the other end of the other lower electrode 300 are electrically coupled to each other, so that the photovoltaic elements may be connected in series with each other.

The insulating layer 400 may be formed as an entire layer divided into the upper electrode 200 and the lower electrode 300 to insulate it. However, in order to improve the overall light transmittance, the insulating layer 400 may be formed only around the base particle 110 of the particle unit 100a for photovoltaic power generation. At this time, the insulating layer 400 only needs to insulate the lower electrode 300 and the thin oxide layer 120, the diffusion layer 130, and the transparent electrode layer 160 of the photovoltaic particle unit 100a, so the lower electrode 300 An area where the thin film oxide layer 120, the diffusion layer 130, and the transparent electrode layer 160 are not present, and the lower electrode 300 is not located under the thin film oxide layer 120, the diffusion layer 130, and the transparent electrode layer 160. It may not be formed in the region.

The second embodiment of the silicon particle unit

2A is a cross-sectional view showing a particle unit for photovoltaic power generation according to another embodiment of the present invention.

Referring to FIG. 2A, the photovoltaic particle unit 100b includes a base particle 110, a thin oxide layer 120 formed outside the base particle 110, a diffusion layer 130 formed outside the thin oxide layer 120, A high concentration layer 140 formed outside the diffusion layer, and a transparent conductive layer 160 formed outside the high concentration layer 140. Compared with the embodiment of FIG. 1A, a high concentration layer 140 is added between the diffusion layer 130 and the transparent conductive layer 160.

The functions and configurations of the base particle 110, the thin oxide layer 120, the diffusion layer 130, and the transparent conductive layer 160 are substantially consistent with the embodiment of FIG. 1A, and focus on the newly added high-concentration layer 140. The characteristics of this embodiment will be described.

The high-concentration layer 140 is formed on the diffusion layer 130 responsible for one configuration of the P-N junction. The high concentration layer 140 may be formed of amorphous silicon doped with a high concentration of impurities of the same series as the diffusion layer 130. For example, when the diffusion layer 130 is an N layer, the high concentration layer 140 is also doped with an N-based impurity, and vice versa, using a P-based impurity. The high concentration layer 140 may be formed to a thickness of approximately 5 nm to 500 nm. In addition, the high concentration layer 140 may be formed by replacing amorphous silicon (A-Si) with a thin film oxide.

The high concentration layer 140 is formed outside the diffusion layer 130 to form a high-low junction. It is possible to improve the open-circuit voltage Voc by bonding the heavily doped amorphous silicon layer of the high concentration layer 140 and the doped polysilicon layer of the diffusion layer 130.

In addition, by playing a role of preventing metal impurities that may penetrate from the transparent conductive layer 160 from being directly injected into the diffusion layer 130, the open circuit voltage Voc may also be improved.

This is because, from a different perspective, it is possible to function as a passivation layer on the surface of the bulk silicon of the diffusion layer 130 and the bulk silicon of the diffusion layer 130 by hydrogen (Hydrogen) in the amorphous silicon of the high concentration layer 140 , It is possible to improve the short-circuit current (Jsc) and the open-circuit voltage (Voc).

2B is a cross-sectional view showing an electrode formed in the particle unit for photovoltaic power generation according to the embodiment of FIG. 2A.

Referring to FIG. 2B, an upper electrode 200, a lower electrode 300, and an insulating layer 400 are formed on the particle unit 100b for photovoltaic power generation according to the embodiment of FIG. 2A. A plurality of units as shown in FIG. 2B are formed to form one solar cell.

The overall configuration of the photovoltaic particle unit 100b, the upper electrode 200, the lower electrode 300, and the insulating layer 400 are substantially similar to the embodiment of FIG. 1B. However, similar to the relationship between the embodiment of FIG. 1A and the embodiment of FIG. 2A, the high concentration layer 140 is further added.

Therefore, at this time, in order to expose the base particles 110, in addition to some of the thin oxide layer 120, the diffusion layer 130, and the transparent conductive layer 160, a portion of the high concentration layer 140 is removed, respectively. Since the structure in which the lower electrode 300 and the upper electrode 200 are disposed and the part in which the insulating layer 400 is formed are substantially similar, a duplicate description will be omitted.

Third embodiment of silicon particle unit

3A is a cross-sectional view showing a particle unit for photovoltaic power generation according to another embodiment of the present invention.

3A, the photovoltaic particle unit 100c includes a base particle 110, a thin oxide layer 120 formed outside the base particle 110, a diffusion layer 130 formed outside the thin oxide layer 120, Anti-reflection-passivation layers 150a to 150d formed outside the diffusion layer, and a transparent conductive layer 160 formed outside the anti-reflection-passivation layers 150a to 150d. Compared with the embodiment of FIG. 1A, anti-reflection-passivation layers 150a to 150d are added between the diffusion layer 130 and the transparent conductive layer 160.

The functions and configurations of the base particle 110, the thin oxide layer 120, the diffusion layer 130, and the transparent conductive layer 160 are substantially consistent with the embodiment of FIG. 1A, and are newly added antireflection-passivation layers 150a to The characteristics of this embodiment will be described focusing on 150d).

The anti-reflection-passivation layers 150a to 150d are formed on the diffusion layer 130. The anti-reflection-passivation layers 150a to 150d may be composed of a single layer that simultaneously performs the role of passivation and anti-reflection, or may be formed in a dual stack structure of a passivation layer and an anti-reflection layer. The anti-reflection-passivation layers 150a to 150d may be made of SiNx, AlOx, SiOx, or the like.

The anti-reflection-passivation layers 150a to 150d are entirely composed of a single or dual stack layer, and then laser ablation, etc., to form an electrical connection path between the diffusion layer 130 and the transparent conductive layer 160 The opening 180 is formed by the method. For this reason, the anti-reflection-passivation layer may also be formed in a structure including a plurality of openings 180.

The anti-reflection-passivation layer (150a to 150d) has a thickness of 20 nm to 200 nm in the case of SiNx, 20 nm to 200 nm in the case of SiOx, and a thickness of 20 nm to 200 nm in the case of a SiOx/SiNx dual stack structure. In case, it may be formed to a thickness of 20 nm to 200 nm.

As described above, the anti-reflection-passivation layers 150a to 105d can simultaneously serve as an anti-reflection layer and a passivation layer. The anti-reflection layer suppresses the reflection of incident light, thereby reducing the short-circuit current (Jsc). Improvement is possible. In addition, since the diffusion layer 130 formed of polysilicon and the transparent conductive layer 160 do not directly contact each other as the passivation layer, they are in point or line contact, so that the open-circuit voltage (Voc) is reduced by the effect of passivation and reduction of recombination It can be improved.

3B is a cross-sectional view showing an electrode formed in the particle unit for photovoltaic power generation according to the embodiment of FIG. 3A.

Referring to FIG. 3B, an upper electrode 200, a lower electrode 300, and an insulating layer 400 are formed on the particle unit 100b for photovoltaic power generation according to the embodiment of FIG. 3A. A plurality of units as shown in FIG. 3B are formed to form one solar cell.

The overall configuration of the photovoltaic particle unit 100b, the upper electrode 200, the lower electrode 300, and the insulating layer 400 are substantially similar to the embodiment of FIG. 1B. However, similar to the relationship between the embodiment of FIG. 1A and the embodiment of FIG. 3A, the anti-reflection-passivation layers 150a to 150d are further added.

Therefore, at this time, in order to expose the base particles 110, in addition to a portion of the thin oxide layer 120, the diffusion layer 130, and the transparent conductive layer 160, a portion of the anti-reflection-passivation layers 150a to 150d, respectively Although the removal point is different, since the structure in which the lower electrode 300 and the upper electrode 200 are disposed and the portion in which the insulating layer 400 is formed are substantially similar, a duplicate description will be omitted.

The present invention is not limited by the above-described embodiments and the accompanying drawings. It will be apparent to those of ordinary skill in the art to which the present invention pertains, that components according to the present invention can be substituted, modified, and changed within the scope of the technical spirit of the present invention.

Claims (14)

Base particles;
A thin oxide layer formed outside the base particle;
A diffusion layer formed outside the thin oxide layer;
A transparent conductive layer formed outside the diffusion layer;
Upper electrode;
Lower electrode; And
And an insulating layer insulating between the lower electrode and the thin film oxide layer, the diffusion layer, and the transparent conductive layer,
The base particle includes an exposed portion, and one end of the lower electrode is electrically connected to the exposed base particle to form an electrode of an optical power plant,
One end of the upper electrode is electrically connected to the transparent conductive layer to form another electrode of the optical power plant,
The other end of the upper electrode of the optical power plant and the other end of the lower electrode of the optical power plant adjacent to the optical power plant are electrically coupled to form a series connection between the optical power plants,
The insulating layer is formed by being divided into a plurality of particles so as to be formed only around the base particles.
The method of claim 1,
Particle unit for photovoltaic power generation further comprising a; a high concentration layer formed outside the diffusion layer.
The method of claim 1,
Particle unit for photovoltaic power generation further comprising a; anti-reflection-passivation layer formed outside the diffusion layer.
The method of claim 1,
Particle unit for photovoltaic power generation, characterized in that the base particle is a doped silicon ball.
The method of claim 1,
Particle unit for photoelectric power generation, characterized in that the thin oxide layer has a thickness of 0.5 to 20nm.
The method of claim 1,
The diffusion layer is a particle unit for photovoltaic power generation, characterized in that the polysilicon layer having a thickness of 5 to 2000nm.
The method of claim 2,
The high concentration layer is an amorphous silicon layer doped with a high concentration of impurities of the same series as the diffusion layer.
The method of claim 3,
The anti-reflection-passivation layer is a particle unit for photovoltaic power generation, characterized in that the diffusion layer and the transparent conductive layer are electrically connected to each other by including an opening.
In a transparent solar cell comprising a plurality of photovoltaic particle units, a plurality of lower electrodes, a plurality of upper electrodes, and an insulating layer,
The photovoltaic particle unit,
A partially exposed base particle;
A thin oxide layer formed outside the base particle;
A diffusion layer formed outside the thin oxide layer; And
Includes; a transparent conductive layer formed outside the diffusion layer,
One end of the plurality of lower electrodes is electrically connected to the exposed particles of the photovoltaic particle unit, respectively,
The other ends of the plurality of lower electrodes are electrically connected to one end of the plurality of upper electrodes, respectively,
The other ends of the plurality of upper electrodes are electrically connected to the transparent conductive layer of the photovoltaic particle unit, respectively,
Wherein the insulating layer insulates between the plurality of lower electrodes and the thin oxide layer, the diffusion layer, and the transparent conductive layer of the particle unit, and is formed by being divided into a plurality so as to be formed only around the base particle. A transparent solar cell using a particle unit for use.
The method of claim 9,
A transparent solar cell using a particle unit for photovoltaic power generation, further comprising an optically transparent layer surrounding the plurality of photovoltaic particle units.
The method of claim 9,
The insulating layer is formed by being divided into a plurality of, and is formed only around the base particle of each of the photovoltaic particle units, a transparent solar cell using a particle unit for photovoltaic power generation.
The method of claim 9,
Each of the photovoltaic particle units is a high concentration layer formed outside the diffusion layer; a transparent solar cell using a photovoltaic particle unit further comprising.
The method of claim 9,
Each of the photovoltaic particle units is a transparent solar cell using a photovoltaic particle unit, characterized in that it further comprises an antireflection-passivation layer formed outside the diffusion layer.
The method of claim 13,
The anti-reflection-passivation layer of each of the photovoltaic particle units includes an opening to electrically connect the diffusion layer and the transparent conductive layer therein to a transparent solar cell using photovoltaic particle units.

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