TWI689170B - Solar cell - Google Patents

Abstract

A solar cell includes a first type semiconductor, a second type semiconductor, first electrodes, a first light blocking member and second electrodes. The first type semiconductor is disposed on the second type semiconductor. The first electrodes are disposed on the first type of semiconductor and are separated by a first gap. The first light blocking member is disposed on the first type semiconductor and shields a portion of the first type semiconductor overlapping the first gap. The second electrodes are disposed on the second type semiconductor, respectively disposed corresponding to the first electrodes, and separated by a second gap. In addition, another solar cell is also be proposed.

Description

Solar battery

The invention relates to a solar cell, and in particular to a silicon-based solar cell.

With the development of science and technology and economy, the use of energy, such as oil, natural gas, coal, etc., are all polluting energy sources, which will lead to increasingly serious environmental damage. Moreover, these polluting energy sources are gradually facing the problem of shortage. Therefore, non-polluting and renewable energy sources are receiving more and more attention.

One way to obtain renewable energy is to use solar cell modules to convert light into electrical energy. The solar cell module includes multiple solar cells. To provide a high voltage, multiple solar cells can be connected in series with each other using a bus element. However, the volume of the solar cell module formed in this way is too large, which is not conducive to installation or application in various electronic devices. In addition, the welding of the solar cell and the bus element causes a loss of battery performance.

A solar cell according to an embodiment of the invention includes a first-type semiconductor, a second-type semiconductor, a plurality of first electrodes, a first shading member, and a plurality of second electrodes. The first type semiconductor is located on the second type semiconductor. The plurality of first electrodes are located on the first-type semiconductor and separated by the first gap to be electrically connected to the first-type semiconductor. The first light blocking member is located on the first type semiconductor, and shields a part of the first type semiconductor overlapping with the first gap. The plurality of second electrodes are located on the second-type semiconductor, respectively disposed corresponding to the plurality of first electrodes, and separated by the second gap, so as to be electrically connected to the second-type semiconductor.

A solar cell according to another embodiment of the present invention includes a plurality of first-type semiconductor patterns, a second-type semiconductor, a plurality of first electrodes, and a plurality of second electrodes. The plurality of first-type semiconductor patterns are separated from each other. A plurality of first-type semiconductor patterns are located on the second-type semiconductor. The plurality of first electrodes are respectively located on the plurality of first-type semiconductor patterns, and are separated by the first gap, so as to be electrically connected to the plurality of first-type semiconductor patterns. The plurality of second electrodes are located on the second-type semiconductor, respectively disposed corresponding to the plurality of first electrodes, and separated by the second gap, so as to be electrically connected to the second-type semiconductor.

Based on the above, the solar cell according to an embodiment of the present invention can provide high voltage (greater than 1 volt) and good electrical performance.

In order to make the above-mentioned features and advantages of the present invention more obvious and understandable, the embodiments are specifically described below in conjunction with the accompanying drawings for detailed description as follows.

Reference will now be made in detail to exemplary embodiments of the present invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same element symbols are used in the drawings and description to denote the same or similar parts.

FIG. 1 is a schematic top view of a solar cell according to an embodiment of the invention. 2 is a schematic cross-sectional view of a solar cell according to an embodiment of the invention. Fig. 2 corresponds to the section line A-A' of Fig. 1.

Referring to FIGS. 1 and 2, the solar cell 10 includes a first type semiconductor 110, a second type semiconductor 120, a plurality of first electrodes 130 and a plurality of second electrodes 140. The first type semiconductor 110 is located on the second type semiconductor 120 to form a PN junction. In this embodiment, the second type semiconductor 120 may be a P-type silicon substrate, and the first type semiconductor 110 may be an N-type doped layer. However, the present invention is not limited to this. According to other embodiments, the first type semiconductor 110 and the second type semiconductor 120 may also be of other types. For example, in another embodiment, the second type semiconductor 120 may be an N-type silicon substrate, and the first type semiconductor 110 may be a P-type doped layer.

The plurality of first electrodes 130 are located on the first-type semiconductor 110 and separated by the first gap G1 to be electrically connected to the first-type semiconductor 110 respectively. The first electrode 130 may also be called a front electrode. The first electrode 130 is provided on the light-receiving surface of the solar cell 10. The first electrode 130 is a patterned electrode. For example, in this embodiment, the first electrode 130 may be a grid electrode. However, the present invention is not limited to this. According to other embodiments, the shape of the first electrode 130 may be appropriately changed according to actual needs.

The plurality of second electrodes 140 are located on the second-type semiconductor 120 and are respectively disposed corresponding to the plurality of first electrodes 130. For example, in this embodiment, the positions of the plurality of second electrodes 140 may overlap the positions of the plurality of first electrodes 130, respectively. The plurality of second electrodes 140 are separated by a second gap G2 to be electrically connected to the second type semiconductor 120 respectively. The second electrode 140 may also be called a back electrode. For example, in this embodiment, the second electrode 140 may be a rectangular electrode overlapping the first electrode 130. However, the present invention is not limited to this, and according to other embodiments, the shape of the second electrode 140 may be appropriately changed according to actual needs.

A first electrode 130, a second electrode 140 provided corresponding to the first electrode 130, a portion of the first type semiconductor 110 and a portion of the first electrode 130 interposed between the first electrode 130 and the second electrode 140 The second type semiconductor 120 may form one sub-cell U. The solar cell 10 includes a plurality of sub-cells U connected in series with each other to provide a high voltage (greater than 1 volt, for example: 2 volts, 4 volts, 6 volts, 8 volts, 10 volts, or 12 volts). The multiple sub-cells U are formed using the same semiconductor structure C (silicon wafer substrate). Therefore, in addition to providing a high voltage, the solar cell 10 has the advantage of small size, which is advantageous for installation or use in various electronic devices (such as but not (Limited to: mobile power, electric vehicles, lighting, traffic signs).

There are many possibilities for connecting multiple sub-cells U in series with each other, and the present invention is not limited thereto. For example, in an embodiment, each sub-cell U may further include a first wire (not shown) and a first wire (not shown) disposed outside the semiconductor structure C and electrically connected to the first electrode 130 and the second electrode 140, respectively Two leads (not shown), wherein the first lead of one sub-cell U of two adjacent sub-cells U is electrically connected to the second lead of the other sub-cell U of two adjacent sub-cells U to form a series circuit. In another embodiment, part of the first type semiconductor 110 and part of the second type semiconductor 120 of each sub-cell U may have a through hole (not shown), and the first electrode 130 of one sub-cell U may be filled in The through hole is electrically connected to the second electrode 140 of the other sub-cell U to form a series circuit.

It is worth noting that, in this embodiment, the solar cell 10 further includes a first shading member 150. The first light blocking member 150 is located on the first type semiconductor 110 and shields a part of the first type semiconductor 110 and a part of the second type semiconductor 120 overlapping with the first gap G1. In other words, the first light-shielding member 150 shields the PN junction between the adjacent sub-cells U to avoid exposure to external light, so it can avoid the occurrence of leakage and improve the electrical performance of the solar cell 10.

In addition, since the first light blocking member 150 can reduce the leakage phenomenon, the plurality of first electrodes 130 of two adjacent sub-cells U can be closer together, so that the area of the semiconductor structure C can be fully utilized to generate electricity, which can provide high voltage and have Small volume solar cell 10. For example, in this embodiment, the width d of the first gap G1 (that is, the distance between the first electrodes 130 of two adjacent sub-cells U) may be greater than or equal to 1 cm, but the present invention does not use this Limited.

In the present embodiment, the solar cell 10 may also selectively include the second light blocking member 160. The second light blocking member 160 is located on the second type semiconductor 120 and shields a part of the second type semiconductor 120 overlapping with the second gap G2.

Similarly, the second light-shielding member 160 shields the PN junction between the adjacent sub-cells U to prevent the external light from irradiating it, so that the leakage phenomenon can be avoided and the electrical performance of the solar cell 10 can be improved. Since the second light blocking member 160 can reduce the leakage phenomenon, the plurality of second electrodes 140 of the two adjacent sub-cells U can be closer, and then the area of the semiconductor structure C can be fully utilized to generate electricity, which can provide a high voltage and have a small volume. Solar cell 10.

In this embodiment, the first light blocking member 150 may directly contact the first type semiconductor 110, but the invention is not limited thereto. In this embodiment, the second light blocking member 160 may directly contact the second type semiconductor 120, but the invention is not limited thereto.

The first shading member 150 and the second shading member 160 can be made of conductive material, insulating material or a combination thereof. For example, the first shading member 150 may include an aluminum foil, a shading glue, a composite material or a combination thereof, and the second shading member 160 may include an aluminum foil, a shading glue, a composite material or a combination thereof, wherein the composite material may Optionally, it includes a polymer substrate and a plurality of inorganic particles, as long as it can achieve the shading effect and do not allow external light to shine, the invention is not limited to this.

In this embodiment, the first shading member 150 and the second shading member 160 can be selectively made of an insulating material, and the first shading member 150 can be in contact with a plurality of adjacent first electrodes 130, and the second shading member 160 may contact a plurality of adjacent second electrodes 140. However, the present invention is not limited to this. According to other embodiments, the first shading member 150 and the second shading member 160 can also be made of conductive material, and the first shading member 150 needs to be separated from the first electrode 130, and the second shading member 160 needs to be separated from the second electrode 140, which will be exemplified below with reference to FIGS. 3 and 4.

FIG. 3 is a schematic top view of a solar cell according to another embodiment of the invention. 4 is a schematic cross-sectional view of a solar cell according to another embodiment of the invention. Fig. 4 corresponds to the section line A-A' of Fig. 3.

Referring to FIGS. 3 and 4, the solar cell 10A of this embodiment is similar to the foregoing solar cell 10. The difference between the two is that the solar cell 10A further includes a first insulating pattern 170 and a second insulating pattern 180. The first insulating pattern 170 is disposed at least in the first gap G1, and the first light blocking member 150 may be disposed on the first insulating pattern 170 to be separated from the first electrode 130. In this embodiment, the first light blocking member 150 can be selectively made of conductive material, but the invention is not limited thereto. The second insulating pattern 180 is disposed at least in the second gap G2, and the second light blocking member 160 may be disposed on the second insulating pattern 180 to be separated from the second electrode 140. In this embodiment, the second shading member 160 can be selectively made of conductive material, but the invention is not limited thereto.

5 is a schematic top view of a solar cell according to another embodiment of the invention. 6 is a schematic cross-sectional view of a solar cell according to another embodiment of the invention. Fig. 6 corresponds to the section line A-A' of Fig. 5.

Please refer to FIGS. 5 and 6, the solar cell 20 is similar to the aforementioned solar cell 10, the main difference between the two is that the solar cell 20 has multiple PN junctions disconnected from each other, and it is not necessary to provide the first The light blocking member 150 and/or the second light blocking member 160 can prevent the leakage phenomenon.

Specifically, the solar cell 20 includes a plurality of first-type semiconductor patterns 112, a second-type semiconductor 120, a plurality of first electrodes 130, and a plurality of second electrodes 140. The plurality of first-type semiconductor patterns 112 are separated from each other. A plurality of first-type semiconductor patterns 112 are located on the second-type semiconductor 120 to form a plurality of PN junctions that are disconnected from each other. The plurality of first electrodes 130 are respectively located on the plurality of first-type semiconductor patterns 112 and separated by the first gap G1 to be electrically connected to the plurality of first-type semiconductor patterns 112 respectively. The plurality of second electrodes 140 are located on the second-type semiconductor 120 and are respectively disposed corresponding to the plurality of first electrodes 130 and separated by the second gap G2 to be electrically connected to the second-type semiconductor 120 respectively.

For example, in this embodiment, the second type semiconductor 120 may be a second type semiconductor substrate, and the plurality of first type semiconductor patterns 112 may be formed in the second type semiconductor substrate using a mask A plurality of first-type doped regions, and a portion 122 of the second-type semiconductor 120 exists between the plurality of first-type doped regions (ie, the plurality of first-type semiconductor patterns 112). However, the present invention is not limited to this. According to other embodiments, other suitable methods may be used to form a plurality of PN junctions that are disconnected from each other.

It is worth mentioning that, since the multiple PN junctions of the multiple sub-cells U of the solar cell 20 are disconnected from each other, the multiple sub-cells U can be arranged closer together, and serious leakage phenomena are not likely to occur. That is to say, in this embodiment, the distance between the plurality of first electrodes 130 of the adjacent plurality of sub-cells U (that is, the width d′ of the first gap G1) can be further reduced, for example, the width d′ can be less than or It is equal to 1 cm. In this way, the area of the semiconductor structure C can be used more fully to generate electricity. In addition, it is known from experiments that when the voltage in series is higher (for example, 12 volts or more), the problem of leakage will be more obvious, and the method of the present invention using PN junctions to be disconnected from each other can be effectively solved to achieve a high voltage and have Small volume solar cell 20.

7 is a schematic top view of a solar cell according to an embodiment of the invention. 8 is a schematic cross-sectional view of a solar cell according to an embodiment of the invention. Fig. 8 corresponds to the section line A-A' of Fig. 7.

Referring to FIGS. 7 and 8, the solar cell 20A is similar to the foregoing solar cell 20. The main difference between the two is that the solar cell 20A further includes a first light blocking member 150 and a second light blocking member 160. The first light blocking member 150 and the plurality of first electrodes 130 are disposed on the first side of the second type semiconductor 120 (eg, above the second type semiconductor 120), and shield the second type semiconductor 120 overlapping the first gap G1 Part 122. The second light blocking member 160 and the plurality of second electrodes 140 are disposed on the second side of the second type semiconductor 120 (for example, below the second type semiconductor 120), and shield the second type semiconductor 120 overlapping the second gap G2 Part 122.

9 is a schematic top view of a solar cell according to another embodiment of the invention. 10 is a schematic cross-sectional view of a solar cell according to another embodiment of the invention. Fig. 10 corresponds to the section line A-A' of Fig. 9.

9 and 10, the solar cell 20B is similar to the aforementioned solar cell 20, and the main difference between the two is that the method of forming a plurality of PN junctions disconnected from each other of the solar cell 20B and the solar cell 20 The method of forming a plurality of PN junctions that are disconnected from each other is different.

Specifically, in this embodiment, a first-type semiconductor (not shown) and a second-type semiconductor 120 that are phase-stacked can be formed first; then, formed on the stacked structure of the first-type semiconductor and the second-type semiconductor 120 The groove K is for breaking the first type semiconductor into a plurality of first type semiconductor patterns 112 separated from each other. The plurality of first-type semiconductor patterns 112 and the second-type semiconductor 120 have a plurality of PN junctions that are disconnected from each other.

For example, in this embodiment, the groove K may be formed by laser. However, the present invention is not limited to this, and according to other embodiments, it can also be formed by other suitable methods. The groove K is defined by the plurality of sidewalls 112a of the plurality of first-type semiconductor patterns 112 and a portion of the surface 120a of the second semiconductor 120 overlapping the first gap G1. In this embodiment, the width of the groove K is W, and 100 μm≦W≦300 μm, but the present invention is not limited to this.

11 is a schematic top view of a solar cell according to another embodiment of the invention. 12 is a schematic cross-sectional view of a solar cell according to another embodiment of the invention. Fig. 12 corresponds to the section line A-A' of Fig. 11.

11 and 12, the solar cell 20C is similar to the foregoing solar cell 20B. The main difference between the two is that the solar cell 20C further includes an insulating material 190 disposed in the groove K, which can further improve the leakage problem. For example, the insulating material 190 includes nitric oxide, silicon monoxide, a ceramic powder, or a combination thereof, but the invention is not limited thereto. In addition, the solar cell 20C further includes a first light blocking member 150 and a second light blocking member 160. The first light blocking member 150 and the plurality of first electrodes 130 are disposed on the first side of the second type semiconductor 120 (for example, above the second type semiconductor 120 ), and shield the groove K. The second light blocking member 160 and the plurality of second electrodes 140 are disposed on the second side of the second type semiconductor 120 (for example, below the second type semiconductor 120), and shield the second type semiconductor 120 overlapping the second gap G2 Part 122.

In summary, the solar cell according to an embodiment of the present invention includes a first type semiconductor, a second type semiconductor, a plurality of first electrodes, and a plurality of second electrodes. The plurality of first electrodes are located on the first-type semiconductor and separated by the first gap to be electrically connected to the first-type semiconductor. The plurality of second electrodes are located on the second-type semiconductor, respectively disposed corresponding to the plurality of first electrodes, and separated by the second gap, so as to be electrically connected to the second-type semiconductor.

A first electrode, a second electrode provided corresponding to the first electrode, and a part of the first type semiconductor and a part of the second type semiconductor interposed between the first electrode and the second electrode may form a sub-cell. The solar cell includes a plurality of sub-cells connected in series with each other to provide a high voltage. Multiple sub-cells are formed using the same semiconductor structure. Therefore, in addition to providing high voltage, solar cells have the advantage of small size, which is advantageous for installation or use in various electronic devices. More importantly, the solar cell further includes a first light-shielding member located on the first-type semiconductor and shielding a portion of the first-type semiconductor overlapping the first gap. The first light-shielding member is used to shield the PN junction between adjacent sub-cells to avoid exposure to external light, so that the leakage phenomenon can be avoided and the electrical performance of the solar cell can be improved.

A solar cell according to another embodiment of the present invention includes a plurality of first-type semiconductor patterns, a second-type semiconductor, a plurality of first electrodes, and a plurality of second electrodes. The plurality of first-type semiconductor patterns are separated from each other. A plurality of first-type semiconductor patterns are located on the second-type semiconductor to form a plurality of PN junctions that are disconnected from each other. The plurality of first electrodes are respectively located on the plurality of first-type semiconductor patterns, and are separated by the first gap, so as to be electrically connected to the plurality of first-type semiconductor patterns. The plurality of second electrodes are located on the second-type semiconductor, respectively disposed corresponding to the plurality of first electrodes, and separated by the second gap, so as to be electrically connected to the second-type semiconductor.

A first electrode, a second electrode provided corresponding to the first electrode, a first type semiconductor pattern and a portion of the second type semiconductor interposed between the first electrode and the second electrode may form a sub-cell. The solar cell includes a plurality of sub-cells connected in series with each other to provide a high voltage. Multiple sub-cells are formed using the same semiconductor structure. Therefore, in addition to providing high voltage, solar cells have the advantage of small size, which is advantageous for installation or use in various electronic devices. More importantly, since the multiple PN junctions of the multiple sub-cells of the solar cell are disconnected from each other, the multiple sub-cells can be placed closer together, and serious leakage phenomena are less likely to occur.

Although the present invention has been disclosed as above with examples, it is not intended to limit the present invention. Any person with ordinary knowledge in the technical field can make some changes and modifications without departing from the spirit and scope of the present invention. The scope of protection of the present invention shall be subject to the scope defined in the appended patent application.

10, 10A, 20, 20A, 20B, 20C: solar cells 110: Type 1 semiconductor 112: Type 1 semiconductor pattern 112a: side wall 120: Type 2 semiconductor 120a: surface 122: part 130: first electrode 140: second electrode 150: The first shading piece 160: second light shield 170: First insulation pattern 180: second insulation pattern 190: Insulation material A-A’: section line C: Semiconductor structure d, d’: width G1: first gap G2: second gap K: groove U: Sub battery W: width

FIG. 1 is a schematic top view of a solar cell according to an embodiment of the invention. 2 is a schematic cross-sectional view of a solar cell according to an embodiment of the invention. FIG. 3 is a schematic top view of a solar cell according to another embodiment of the invention. 4 is a schematic cross-sectional view of a solar cell according to another embodiment of the invention. 5 is a schematic top view of a solar cell according to another embodiment of the invention. 6 is a schematic cross-sectional view of a solar cell according to another embodiment of the invention. 7 is a schematic top view of a solar cell according to an embodiment of the invention. 8 is a schematic cross-sectional view of a solar cell according to an embodiment of the invention. 9 is a schematic top view of a solar cell according to another embodiment of the invention. 10 is a schematic cross-sectional view of a solar cell according to another embodiment of the invention. 11 is a schematic top view of a solar cell according to another embodiment of the invention. 12 is a schematic cross-sectional view of a solar cell according to another embodiment of the invention.

10: Solar cell

110: Type 1 semiconductor

120: Type 2 semiconductor

130: first electrode

140: second electrode

150: The first shading piece

160: second light shield

A-A’: section line

C: Semiconductor structure

G1: first gap

G2: second gap

U: Sub battery

Claims (14)

A solar cell includes: a first type semiconductor; a second type semiconductor, wherein the first type semiconductor is located on the second type semiconductor; a plurality of first electrodes are located on the first type semiconductor, and are A gap is separated to be electrically connected to the first-type semiconductor; a first light-shielding member is located on the first-type semiconductor and shields a portion of the first-type semiconductor overlapping the first gap; and A second electrode is located on the second-type semiconductor, respectively corresponding to the first electrodes, and is separated by a second gap to be electrically connected to the second-type semiconductor. The solar cell as described in item 1 of the patent application range, wherein the first light blocking member directly contacts the first type semiconductor. The solar cell as described in item 1 of the patent application scope further includes: a first insulating pattern disposed at least on the first gap, wherein the first light blocking member is disposed on the first insulating pattern. The solar cell as described in item 1 of the patent application scope further includes: a second light-shielding member located on the second-type semiconductor and shielding a part of the second-type semiconductor overlapping the second gap. The solar cell as described in item 4 of the patent application range, wherein the second light blocking member directly contacts the second type semiconductor. The solar cell as described in item 4 of the patent application scope further includes: a second insulating pattern disposed at least on the second gap, wherein the second light blocking member is disposed on the second insulating pattern. The solar cell according to item 1 of the patent application scope, wherein the first shading member comprises: an aluminum foil, a shading glue, a composite material or a combination thereof. The solar cell as described in item 7 of the patent application range, wherein the composite material includes a polymer substrate and a plurality of inorganic particles. A solar cell includes: a plurality of first-type semiconductor patterns separated from each other; a second-type semiconductor, wherein the first-type semiconductor patterns are located on the second-type semiconductor; a plurality of first electrodes are respectively located on the first On a semiconductor pattern of a type and separated by a first gap to be electrically connected to the semiconductor patterns of the first type; and a plurality of second electrodes on the semiconductor of the second type corresponding to the first The electrodes are arranged and separated by a second gap to be electrically connected to the second semiconductor. The solar cell as described in item 9 of the patent application range, wherein a plurality of sidewalls of the first type semiconductor patterns and a portion of the second semiconductor surface overlapping the first gap define a groove. The solar cell as described in item 10 of the patent application scope further includes: an insulating material disposed in the groove. The solar cell as described in item 11 of the patent application range, wherein the insulating material includes nitric oxide, silicon monoxide, a ceramic powder, or a combination thereof. The solar cell as described in item 9 of the scope of the patent application further includes: a first light-shielding member, and the first electrodes are disposed on a first side of the second type semiconductor, and shield the overlap with the first gap Part of the second type semiconductor. The solar cell as described in item 9 of the scope of the patent application further includes: a second light-shielding member, and the second electrodes are disposed on a second side of the second-type semiconductor, and shield the overlap with the second gap Part of the second type semiconductor.

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