KR101154663B1 - Solar cell apparatus - Google Patents

Abstract

A photovoltaic device is disclosed. The solar cell apparatus includes a support substrate having a cell region and a transmission region adjacent to the cell region; A first backside electrode disposed in the cell region and transparent; A second back electrode disposed on the first back electrode; A light absorbing part disposed on the second back electrode; A window disposed on the light absorbing portion; And a connection part disposed in the transmission area and extending from the first back electrode.

BIPV, Solar, AZO, Transparent, back contact

Description

SOLAR CELL APPARATUS {SOLAR CELL APPARATUS}

Embodiments relate to a photovoltaic device.

Photovoltaic modules that convert light energy into electrical energy using photoelectric conversion effects are widely used as a means of obtaining pollution-free energy that contributes to the preservation of the global environment.

As photovoltaic conversion efficiency of solar cells is improved, many solar power systems with photovoltaic modules have been installed outside of commercial buildings as well as in residential applications.

The embodiment has an improved electrical characteristic and is intended to provide a photovoltaic device that can be used for windows and doors.

In one embodiment, a solar cell apparatus includes: a support substrate having a cell region and a transmission region adjacent to the cell region; A first backside electrode disposed in the cell region and transparent; A second back electrode disposed on the first back electrode; A light absorbing part disposed on the second back electrode; A window disposed on the light absorbing portion; And a connection part disposed in the transmission area and extending from the first back electrode.

According to an embodiment, there is provided a solar cell apparatus including: a support substrate having a first cell region, a second cell region next to the first cell region, and a transmission region defined between the first cell region and the second cell region; A first transparent back electrode disposed in the first cell region; A first light absorbing part disposed on the first transparent back electrode; A first window disposed on the first light absorbing portion; A second transparent back electrode disposed in the second cell region; And a connection part extending from the second transparent back electrode and disposed in the transmission area and connected to the first window.

The photovoltaic device according to the embodiment is disposed in the transmission region and includes a connecting portion extending from the first back electrode. In this case, the connection part may be integrally formed with the first back electrode and may be transparent.

Accordingly, a short circuit between the connection part and the first back electrode may be prevented, and the connection part may have improved connection characteristics with the first back electrode.

In addition, the window may be formed of the same material as the connection part and the first back electrode. Accordingly, when the adjacent window and the connecting portion are connected to each other, the connecting portion may have improved connection characteristics with the adjacent window.

Accordingly, each cell has improved connection properties, and the connection can be transparent and can be disposed in the transmissive area to allow light to pass through.

Therefore, the solar cell apparatus according to the embodiment has improved electrical characteristics and can be used for windows.

In the description of the embodiments, it is described that each substrate, film, electrode, groove or layer or the like is formed "on" or "under" of each substrate, electrode, film, groove or layer or the like. In the case, “on” and “under” include both being formed “directly” or “indirectly” through other components. In addition, the upper or lower reference of each component is described with reference to the drawings. The size of each component in the drawings may be exaggerated for the sake of explanation and does not mean the size actually applied.

1 is a plan view illustrating a solar cell panel according to an embodiment. FIG. 2 is a cross-sectional view illustrating a cross section taken along line AA ′ in FIG. 1.

1 and 2, a solar cell panel according to an embodiment includes a support substrate 10, a back electrode layer 100, a light absorbing layer 200, a buffer layer 300, a high resistance buffer layer 400, and a window layer ( 500).

The support substrate 10 has a plate shape and supports the back electrode layer 100, the light absorbing layer 200, the buffer layer 300, the high resistance buffer layer 400, and the window layer 500.

The support substrate 10 may be an insulator. The support substrate 10 may be a glass substrate, a plastic substrate, or a metal substrate. In more detail, the support substrate 10 may be a soda lime glass substrate. The support substrate 10 may be transparent. The support substrate 10 may be rigid or flexible.

As illustrated in FIG. 1, a plurality of cell regions C1, C2..., A plurality of transmission regions TA and an outer region OA may be defined in the support substrate 10. That is, the support substrate 10 may be divided into the cell regions C1, C2..., The transmission regions TA, and the outer region OA.

The cell regions C1, C2... And the transmission regions TA are alternately arranged. In addition, the cell regions C1, C2... And the transmission regions TA may have a shape extending in one direction and may be disposed in parallel with each other.

In FIG. 1, four cell regions C1, C2... And three transmission regions TA are shown, but are not limited thereto. A larger number of cell regions and transmission regions may be defined. .

The outer region OA surrounds the cell regions C1, C2... And the transmission regions TA. The outer region OA is defined at the outer side of the support substrate 10. The outer region OA has a closed loop shape.

The back electrode layer 100 is disposed on the support substrate 10. The back electrode layer 100 may be formed by depositing on an upper surface of the support substrate 10. The back electrode layer 100 is a conductive layer.

The back electrode layer 100 includes a first back electrode layer 110 and a second back electrode layer 120.

The first back electrode layer 110 is disposed on the support substrate 10. The first back electrode layer 110 may be formed by depositing a transparent conductive material on the support substrate 10. That is, the first back electrode layer 110 contacts the top surface of the support substrate 10.

The first back electrode layer 110 includes a transparent conductor. That is, the first back electrode layer 110 is a transparent conductive layer. In other words, the first backside electrode layer 110 is a transparent electrode layer.

 Examples of the material used as the first back electrode layer 110 include indium tin oxide (ITO), indium zinc oxide (IZO), tin oxide (SnO), or zinc oxide doped with aluminum (AZO). ), And the like.

The second back electrode layer 120 is disposed on the first back electrode layer 110. The second back electrode layer 120 is formed by depositing a conductive material on an upper surface of the first back electrode layer 110. That is, the second backside electrode layer 120 contacts the top surface of the first backside electrode layer 110.

The second back electrode layer 120 includes a conductor. In this case, the second back electrode layer 120 may include an opaque conductor, and the second back electrode layer 120 may be an opaque conductive layer.

The second back electrode layer 120 includes a conductor having a lower resistance than a material used as the first back electrode layer 110. Thus, the second backside electrode layer 120 is a low resistance electrode layer.

Examples of the material used for the second back electrode layer 120 include molybdenum, copper, silver, and the like.

First through holes TH1 are formed in the back electrode layer 100. The first through holes TH1 pass through the first back electrode layer 110 and the second back electrode layer 120. The first through holes TH1 are open regions exposing the top surface of the support substrate 10. The first through holes TH1 may have a shape extending in the one direction when viewed in a plan view.

The first backside electrode layer 110 is divided into a plurality of first backside electrodes 111 and a plurality of connection parts 112 by the first through holes TH1. That is, the first back electrodes 111 and 210 and the connection parts 112 are defined by the first through holes TH1.

The first backside electrode layer 110 is divided by the first through holes TH1 to form the first backside electrodes 111 and the connection portions 112. That is, the first backside electrode layer 110 includes the first backside electrodes 111 and the connection portions 112.

The first back electrodes 111 are disposed in the cell regions C1, C2... And the connection portions 112 are respectively disposed in the transmission regions TA. That is, the connection parts 112 are alternately disposed adjacent to each other with the first back electrodes 111.

That is, the connection part 112 extends from the first back electrodes 111 to the transmission area TA. The connection part 112 and the first back electrode 111 are integrally formed.

The light absorbing layer 200 includes a group I-III-VI compound. For example, the light absorbing layer 200 may be formed of a copper-indium-gallium-selenide-based (Cu (In, Ga) Se ₂ ; CIGS-based) crystal structure, copper-indium-selenide-based, or copper-gallium-selenide It may have a system crystal structure.

The energy band gap of the light absorbing layer 200 may be about 1 eV to 1.8 eV.

The buffer layer 300 is disposed on the light absorbing layer 200. The buffer layer 300 includes cadmium sulfide (CdS), and the energy band gap of the buffer layer 300 is about 2.2 eV to 2.4 eV.

The high resistance buffer layer 400 is disposed on the buffer layer 300. The high resistance buffer layer 400 includes zinc oxide (i-ZnO) that is not doped with impurities. The energy bandgap of the high resistance buffer layer 400 is about 3.1 eV to 3.3 eV.

Second through holes TH2 are formed in the light absorbing layer 200, the buffer layer 300, and the high resistance buffer layer 400. The second through holes TH2 pass through the second back electrode layer 120, the light absorbing layer 200, the buffer layer 300, and the high resistance buffer layer 400. In addition, the second through holes TH2 are open regions exposing the top surface of the back electrode layer 100.

The window layer 500 is disposed on the high resistance buffer layer 400. The window layer 500 is transparent and a conductive layer. Examples of the material used as the window layer 500 may include Al doped ZnO (AZO) doped with aluminum.

Third through holes TH3 are formed in the window layer 500, the high resistance buffer layer 400, the buffer layer 300, the light absorbing layer 200, and the second back electrode layer 120. The third through holes TH3 are open regions exposing the top surface of the first back electrode layer 110. The third through holes TH3 are formed to correspond to the transmission areas TA.

In other words, the third through holes TH3 are formed, and the top surface of the first back electrode layer 110 is exposed to define the transmission areas TA.

The window layer 500 is divided into a plurality of windows 510 by the third through holes TH3. That is, the windows 510 are defined by the third through holes TH3.

In addition, the light absorbing layer 200 defines a plurality of light absorbing portions 210 by the second through holes TH2 and the third through holes TH3. That is, the light absorbing layer 200 is divided into the light absorbing parts 210 by the second through holes TH2 and the third through holes TH3.

Similarly, the buffer layer 300 is defined as a plurality of buffers 310 by the second through holes TH2 and the third through holes TH3, and the high resistance buffer layer 400 is defined by the second through holes TH2 and the third through holes TH3. By the second through holes TH2 and the third through holes TH3, a plurality of high resistance buffers 410 are defined.

In addition, a plurality of solar cells 21, 22... Are defined by the third through holes TH3.

The first through holes TH1, the second through holes TH2, and the third through holes TH3 have a shape extending in the one direction. Accordingly, the solar cells 21, 22... Also have a shape extending in the one direction.

The solar cell panel according to the embodiment includes a plurality of connections 600. The connection parts 600 extend downward from the window layer 500 and directly contact the first back electrode layer 110. For example, the connection part 600 extends downward from a window of a specific solar cell and is connected to a connection part connected to an adjacent solar cell.

Accordingly, the connection parts 600 and the connection parts 112 connect adjacent solar cells.

The connection parts 600 are integrally formed with the windows 510. That is, the material used as the connection parts 600 is the same as the material used as the window layer 500.

The solar cell panel according to the embodiment has connecting parts for connecting the solar cells 21, 22... And the solar cells 21, 22..., Arranged on the support substrate 10. 112).

The solar cells 21, 22... Are disposed one by one in the cell regions C1, C2... Each solar cell 21, 22. 510 and the connector 600.

The first backside electrode 111 is disposed on the support substrate 10, and the second backside electrode 121 is disposed on the first backside electrode 111.

The light absorbing part 210 is disposed on the second back electrode 121. The buffer 310 is disposed on the light absorbing unit 210, and the high resistance buffer 410 is disposed on the buffer 310. The window 510 is disposed on the high resistance buffer 410.

The connection parts 112 are disposed in the transmission areas TA, respectively. The connection parts 112 connect adjacent solar cells to each other.

That is, each connection portion extends from the first back electrode of one of the adjacent solar cells to the transmission area TA. In addition, each connection portion 112 is directly connected to the other connection portion 600 of the adjacent solar cells.

Since the solar cell panel according to the embodiment includes the transmission areas TA, the solar cell panel may be used for windows and the like of a building.

The connection parts 112 and the first back electrodes 111 may be integrally formed. In addition, the first back electrode layer 110, the connection parts 600, and the window layer 500 may be formed of the same material. That is, the connection parts 112 and the connection parts 600 may include a material such as aluminum doped zinc oxide.

Accordingly, the contact characteristics between the connection parts 600 and the connection parts 112 are improved and a short circuit is prevented.

Accordingly, the solar cell panel according to the embodiment may prevent a short circuit between the solar cells 21, 22..., And reduce contact resistance.

Accordingly, the solar cell panel according to the embodiment has improved electrical and silver properties.

3 to 6 are cross-sectional views illustrating a method of manufacturing a solar cell panel according to an embodiment. For a description of the present manufacturing method, refer to the description of the solar cell panel described above. The description of the solar cell panel described above may be essentially combined with the description of the present manufacturing method.

Referring to FIG. 3, a transparent conductive material is deposited on the support substrate 10 to form a first back electrode layer 110. Thereafter, a conductive material having a low resistance is deposited on the first back electrode layer 110 to form a second back electrode layer 120.

The first back electrode layer 110 may be protected by the second back electrode layer 120. That is, in the process of forming the light absorbing layer 200 or the like, damage to the first back electrode layer 110 is prevented by the second back electrode layer 120.

Thereafter, the first backside electrode layer 110 and the second backside electrode layer 120 are patterned to form a plurality of first through holes TH1.

The first through holes TH1 may expose an upper surface of the support substrate 10 and have a width of about 10 μm to 100 μm.

Referring to FIG. 5, the light absorbing layer 200, the buffer layer 300, and the high resistance buffer layer 400 are sequentially formed on the back electrode layer 100.

The light absorbing layer 200 may be formed by a sputtering process or an evaporation method.

For example, copper, indium, gallium, selenide-based (Cu (In, Ga) Se ₂ ; CIGS-based) while evaporating copper, indium, gallium, and selenium simultaneously or separately to form the light absorbing layer 200. The method of forming the light absorbing layer 200 and the method of forming the metal precursor film and forming it by the selenization process are widely used.

When the metal precursor film is formed and selenization is subdivided, a metal precursor film is formed on the back electrode 200 by a sputtering process using a copper target, an indium target, and a gallium target.

Thereafter, the metal precursor film is formed of a copper-indium-gallium-selenide-based (Cu (In, Ga) Se ₂ ; CIGS-based) light absorbing layer 200 by a selenization process.

Alternatively, the copper target, the indium target, the sputtering process using the gallium target, and the selenization process may be performed simultaneously.

Alternatively, the CIS-based or CIG-based light absorbing layer 200 may be formed by using only a copper target and an indium target, or by a sputtering process and a selenization process using a copper target and a gallium target.

Thereafter, cadmium sulfide is deposited on the light absorbing layer 200 by a sputtering process or the like, and the buffer layer 300 is formed.

Thereafter, zinc oxide is deposited on the buffer layer 300 by a sputtering process, and the high resistance buffer layer 400 is formed.

Thereafter, portions of the light absorbing layer 200, the buffer layer 300, the high resistance buffer layer 400, and the second back electrode layer 120 are removed to form second through holes TH2. The second through holes TH2 pass through the light absorbing layer 200, the buffer layer 300, the high resistance buffer layer 400, and the second back electrode layer 120.

The second through hole TH2 may be formed by a mechanical device such as a tip or a laser device.

For example, the second back electrode layer 120, the light absorbing layer 200, the buffer layer 300 and the high resistance buffer layer 400 are patterned by a tip having a width of about 40 μm to about 180 μm. Can be. In addition, the second through holes TH2 may be formed by a laser having a wavelength of about 200 to 600 nm.

Referring to FIG. 5, a window layer 500 is formed on the high resistance buffer layer 400. In this case, a material forming the window layer 500 is filled in the second through holes TH2.

In order to form the window layer 500, a transparent conductive material is stacked on the high resistance buffer layer 400. The transparent conductive material is filled in the entire second through holes TH2. Examples of the transparent conductive material include aluminum doped zinc oxide and the like.

Referring to FIG. 6, a portion of the window layer 500, the high resistance buffer layer 400, the buffer layer 300, the light absorbing layer 200, and the second back electrode layer 120 may be removed to form a third layer. Through grooves TH3 are formed. That is, the portion to be removed is a portion corresponding to the transmission areas TA.

The width of the third through holes TH3 may be about 1 cm to about 10 cm. The third through holes TH3 may be formed by mechanical scribing or a laser.

When the third through holes TH3 are formed of a laser, the laser is formed on the second back electrode layer 120, the light absorbing layer 200, and the buffer layer 300 through the support substrate 10. Can be investigated.

In this case, the first back electrode layer 110, the high resistance buffer layer 400, and the window layer 500 are not removed. In this case, a portion of the window layer 500 and the high resistance buffer layer 400 corresponding to the transmission areas TA may be removed by a mechanical scribing process.

As such, by the method of manufacturing a solar cell panel according to the embodiment, a solar cell panel used for windows and having improved electrical characteristics may be provided.

In addition, the features, structures, effects, and the like described in the above embodiments are included in at least one embodiment of the present invention, and are not necessarily limited to only one embodiment. Furthermore, the features, structures, effects, and the like illustrated in the embodiments may be combined or modified with respect to other embodiments by those skilled in the art to which the embodiments belong. Therefore, it should be understood that the present invention is not limited to these combinations and modifications.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, It will be understood that various modifications and applications are possible. For example, each component specifically shown in the embodiment can be modified. And differences relating to such modifications and applications will have to be construed as being included in the scope of the invention defined in the appended claims.

1 is a plan view illustrating a solar cell panel according to an embodiment.

FIG. 2 is a cross-sectional view illustrating a cross section taken along line AA ′ in FIG. 1.

3 to 6 are cross-sectional views illustrating a method of manufacturing a solar cell panel according to an embodiment.

Claims (9)

A support substrate defining a cell region and a transmission region adjacent to the cell region; A first backside electrode disposed in the cell region and transparent; A second back electrode disposed on the first back electrode; A light absorbing part disposed on the second back electrode; A window disposed on the light absorbing portion; And A connection part disposed in the transmission area and extending from the first back electrode; The second back electrode covers the top surface of the first back electrode, and exposes the top surface of the connection part. One side of the second back electrode is disposed on the same plane as one side of the first back electrode, The other side surface of the second back electrode is located between the cell region and the transmission region. The solar cell apparatus of claim 1, wherein the connection part and the first back electrode are integrally formed. The solar cell apparatus of claim 1, wherein the second back electrode comprises molybdenum. The solar cell apparatus of claim 1, wherein the window and the first back electrode comprise the same material. A support substrate having a first cell region, a second cell region next to the first cell region, and a transmission region defined between the first cell region and the second cell region; A first transparent back electrode disposed in the first cell region; A first light absorbing part disposed on the first transparent back electrode; A first window disposed on the first light absorbing portion; A second transparent back electrode disposed in the second cell region; A connection part extending from the second transparent back electrode and disposed in the transmission area and connected to the first window; And And a first low resistance back electrode interposed between the first transparent back electrode and the first light absorbing portion. 6. The solar cell apparatus according to claim 5, further comprising a connecting portion that penetrates the first light absorbing portion, extends from the first window, and is connected to the connecting portion. The solar cell apparatus of claim 6, wherein the first window, the connection part, and the connection part are made of the same material. The solar cell apparatus of claim 5, wherein the connection part is transparent and directly contacts the support substrate. delete

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