TWM498964U - Solar cell structure - Google Patents

Abstract

A solar cell structure includes a semiconductor substrate, a doped emitter layer on a front side of the substrate, an antireflection layer on the doped emitter layer, and a front bus bar on the antireflection layer. The front bus bar extends along a first direction. At least one gap is disposed on the front bus bar.

Description

Solar cell structure

The present invention relates to the field of solar cell technology, and more particularly to a solar cell structure having an improved front bus bar electrode design.

It is known that the working principle of solar cells is to use solar radiation energy and semiconductor materials to generate electrical energy. The main materials include semiconductor materials such as single crystal germanium, polycrystalline germanium, amorphous germanium germanium or III-V compound. A semiconductor material or the like, and a conductive paste used as an electrode, for example, a silver paste or an aluminum paste.

The solar cell manufacturing method usually performs wafer surface cleaning and roughening treatment, and then performs a diffusion process to form a phosphor glass layer and an emitter emitter region on the surface of the wafer, and then remove the phosphor glass layer by an etching process, and then An anti-reflection layer is formed, and then an electrode pattern is printed on the metal paste web on the front and back sides of the battery by screen printing, and then sintered at a high temperature to form an electrode. Finally, string welding is performed to connect the battery cells in series.

However, in the conventional battery structure, since light is blocked by the electrodes (finger electrodes and bus bar electrodes) on the surface of the battery, light rays irradiated to the electrode regions cannot be effectively utilized. Accordingly, there remains a need in the art for an improved solar cell structure to address the deficiencies and shortcomings of the prior art described above.

The main purpose of this creation is to provide an improved solar cell structure that can increase the light receiving area of the battery, increase the short circuit current (Isc), and thereby increase the photoelectric conversion efficiency.

According to another embodiment of the present invention, the present invention provides a solar cell structure including a semiconductor substrate; a doped emitter layer disposed on a front surface of the semiconductor substrate; and an anti-reflection layer On the doped emitter layer; and at least one front bus bar electrode is disposed on the anti-reflective layer and extends along a first direction, wherein the front bus bar electrode is provided with at least one gap.

According to an embodiment, wherein the gap breaks the front bus bar electrode to form a discontinuous front bus bar electrode.

According to an embodiment, the method further includes at least one finger electrode extending along a second direction, and the first direction is perpendicular to the second direction. According to an embodiment, wherein the finger electrode passes through the gap.

According to an embodiment, a module solder material layer is further disposed on the front bus bar electrode; and a bridging portion spans the gap to connect the module solder material layer.

According to an embodiment, at least one back bus bar electrode is further disposed on the back surface of the semiconductor substrate.

According to an embodiment, a contact electrode is further disposed on the back surface of the semiconductor substrate.

According to another embodiment of the present invention, a solar cell structure includes a semiconductor substrate; a doped emitter layer disposed on a front surface of the semiconductor substrate; and an anti-reflection layer disposed on the doped emitter layer; at least one The front bus bar electrode is disposed on the anti-reflection layer and extends along a first direction, wherein the front bus bar electrode is provided with at least one gap; and at least one bridge is located at the gap. The bridge has a width of 0.1 to 1.0 mm. The method further includes at least one finger electrode extending along a second direction, and the first direction is perpendicular to the second direction. Wherein the finger electrode is connected to the bridge.

The above described objects, features and advantages of the present invention will become more apparent from the following description. However, the following preferred embodiments and drawings are for illustrative purposes only and are not intended to limit the present invention.

1‧‧‧Solar cell structure

1a‧‧‧Solar cell structure

1b‧‧‧Solar cell structure

10‧‧‧Semiconductor substrate

12‧‧‧Doped emitter layer

14‧‧‧Anti-reflective layer

24‧‧‧ Positive bus bar electrode

25‧‧‧Backside bus electrode

26‧‧‧Contact electrode

36‧‧‧ finger electrodes

44‧‧‧Modular welding material layer

126‧‧‧Back surface layer

242‧‧‧ gap

244‧‧‧ Bridge

442‧‧‧Bridge

S1‧‧ positive

S2‧‧‧Back

Fig. 1 is a cross-sectional view showing the structure of the solar cell of the present invention.

Fig. 2 illustrates a bus bar electrode and a finger electrode on the front side of the solar cell structure of the present invention.

Fig. 3 is a partially enlarged side view showing a hollow structure composed of a layer of a solder material of a module.

Figures 4 and 5 illustrate other variations of the present creation.

Please refer to FIG. 1 , which illustrates a cross-sectional view of the solar cell structure of the present invention. As shown in Fig. 1, the solar cell structure 1 includes a semiconductor layer or a semiconductor substrate 10, for example, a P-type doped germanium substrate or a germanium wafer having a thickness of, for example, about 180 to 200 μm. A doped emitter layer 12, for example, an N-type doped emitter layer, and an anti-reflection layer 14, such as tantalum nitride or hafnium oxide, are additionally provided on the front surface (light-receiving surface) S1 of the semiconductor substrate 10.

Further, the front surface S1 of the semiconductor substrate 10 is additionally provided with a front bus bar electrode 24. A back surface bus electrode 25, a back surface electric field layer 126, and a contact electrode 26 are provided on the back surface S2 of the semiconductor substrate 10. Those skilled in the art will appreciate that the above structure is merely illustrative and that the present invention is also applicable to other solar cell structures.

As described above, in the conventional battery structure, since light is blocked by the front bus bar electrode 24 of the battery front surface S1, light irradiated to the electrode region cannot be effectively utilized. In order to solve such problems, the present invention proposes an improved front bus bar electrode design.

First, as shown in FIG. 2, the front bus bar electrode 24 and the finger electrode 36 are first screen printed on the front surface S1 of the solar cell structure 1. The front bus bar electrode 24 and the finger electrode 36 are usually formed by silver paste screen printing. . The number of the front bus bar electrodes 24 is not limited, and may be two, three or four, parallel to each other, extending along the first direction, and the thinner finger electrodes 36 extending along the second direction, wherein the first The direction is perpendicular to the second direction.

According to this embodiment, each of the front bus bar electrodes 24 is discontinuous and has at least one gap 242. For example, in the second figure, each of the bus bar electrodes 24 has three gaps 242, and each bus bar electrode 24 is provided. Divided into four separate segments. According to this embodiment, there may be at least one finger electrode 36 Through the gap 242.

According to this embodiment, the width of the gap 242 may range from 1 to 10 finger electrodes.

Fig. 3 illustrates another technical feature of the present creation in a partially enlarged side view. Similarly, as shown in FIG. 3, the front bus bar electrode 24 and the finger electrode 36 are screen printed on the front surface S1 of the solar cell structure 1. The number of the front bus bar electrodes 24 is not limited, and may be two, three or four, parallel to each other, extending along the first direction, and the thinner finger electrodes 36 extending along the second direction, wherein the first The direction is perpendicular to the second direction. Each of the front bus bar electrodes 24 is discontinuous and has at least one gap 242.

According to the present embodiment, a discontinuous front bus bar electrode 24 of the solar cell structure 1 is further provided with a module solder material layer 44 and connected through a bridging portion 442 spanning the gap 242. According to this embodiment, the bridging portion 442 and the module solder material layer 44 are simultaneously formed and integrally formed.

Therefore, it can be clearly seen from FIG. 3 that the creation constitutes a hollow structure through the gap 242 and the bridging portion 442 spanning the gap 242, so that the light receiving area of the solar module is increased, thereby achieving the purpose of improving the photoelectric conversion efficiency.

Please refer to Figures 4 and 5, which are other variations of the creation.

As shown in FIG. 4, the solar cell structure 1a differs from the solar cell structure 1 of FIG. 2 in that each gap 242 of the solar cell structure 1a is provided with a bridge 244, so that the front bus bar electrode 24 of the solar cell structure 1a is continuously. Further, the bridge 244 may be disposed on the same side of the front bus bar electrode 24. The bridge 244 may have a width of 0.1 to 1.0 mm. According to this embodiment, the finger electrode 36 can be coupled to the bridge 244.

As shown in Fig. 5, the solar cell structure 1b differs from the solar cell structure 1a of Fig. 4 in that the solar cell structure 1b bridges 244 are alternately disposed on different sides of the front bus bar electrodes 24.

The above descriptions are only preferred embodiments of the present invention, and all changes and modifications made by the scope of the patent application of the present invention should be covered by the present invention.

1‧‧‧Solar cell structure

10‧‧‧Semiconductor substrate

24‧‧‧ Positive bus bar electrode

36‧‧‧ finger electrodes

44‧‧‧Modular welding material layer

242‧‧‧ gap

442‧‧‧Bridge

S1‧‧ positive

S2‧‧‧Back

Claims (11)

A solar cell structure comprising: a semiconductor substrate; a doped emitter layer disposed on a front surface of the semiconductor substrate; an anti-reflection layer disposed on the doped emitter layer; and at least one front bus bar electrode, The anti-reflection layer is disposed along a first direction, wherein the front bus bar electrode is provided with at least one gap. The solar cell structure of claim 1, wherein the gap breaks the front bus bar electrode to form a discontinuous front bus bar electrode. The solar cell structure of claim 1, further comprising at least one finger electrode extending along a second direction, wherein the first direction is perpendicular to the second direction. The solar cell structure of claim 3, wherein the finger electrode passes through the gap. The solar cell structure of claim 1, wherein the front bus bar electrode is further provided with: a module solder material layer; and a bridging portion, the bridging portion spans the gap to connect the die Set of layers of solder material. The solar cell structure of claim 1, further comprising at least one back bus bar electrode disposed on a back surface of the semiconductor substrate. The solar cell structure of claim 1, further comprising a contact electrode disposed on a back surface of the semiconductor substrate. A solar cell structure comprising: a semiconductor substrate; a doped emitter layer disposed on a front surface of the semiconductor substrate; an anti-reflection layer disposed on the doped emitter layer; and at least one front bus bar electrode disposed And extending on the anti-reflection layer along a first direction, wherein the front bus bar electrode is provided with at least one gap; and at least one bridge is located at the gap. The solar cell structure of claim 8, wherein the bridge has a width of 0.1 to 1.0 mm. The solar cell structure of claim 8, further comprising at least one finger electrode extending along a second direction, wherein the first direction is perpendicular to the second direction. The solar cell structure of claim 10, wherein the finger electrode is connected to the bridge.