Interlayer grid line TOPCon solar cell structure

Abstract

The utility model discloses an interlayer grid line TOPCon solar cell structure which comprises a first antireflection passivation layer group, a first aluminum oxide layer, a first suede structure layer, a first PN junction layer, a phosphorus-containing silicon base layer, a tunneling silicon oxide layer, a phosphorus-doped polycrystalline silicon layer, a second antireflection passivation layer group and a first silicon oxynitride layer which are arranged from top to bottom in the height direction. A third antireflection passivation layer group, a first silicon nitride layer, a second aluminum oxide layer, a boron-containing silicon base layer, a second PN junction layer, a second suede structure layer, a third aluminum oxide layer and a fourth antireflection passivation layer group; the device further comprises a first electrode group and a second electrode group. The first electrode group is arranged in the phosphorus-doped polycrystalline silicon layer, the second antireflection passivation layer group and the first silicon oxynitride layer in a penetrating manner along a first horizontal direction; the second electrode group is arranged in the first silicon nitride layer, the third antireflection passivation layer group and the first silicon oxynitride layer in a penetrating manner along the first horizontal direction; the first electrode group and the second electrode group are not in contact and are parallel to each other. The solar energy utilization rate is high.

Description

Technical Field

[0001] The utility model relates to the technical field of photovoltaic cells, in particular to a sandwich grid line TOPCon solar cell structure. Background Art

[0002] Solar energy is an inexhaustible renewable energy source for human beings. It is also a clean energy source that does not cause any environmental pollution. Among the effective utilization of solar energy, solar photovoltaic utilization is the fastest growing and most dynamic research field in recent years. To this end, people have studied and developed photovoltaic cells, especially tunneling oxide passivated contact solar cells (TOPCon), which are widely used as a new generation of solar cells.

[0003] However, there is a problem with existing TOPCon solar cells, that is, the shielding of the front and back grid lines will affect the effective use of light energy. When light encounters the grid lines, part of the light will be reflected by the grid line surface, while the other part will pass through the grid lines but will be refracted. These reflection and refraction phenomena will cause the light to scatter when passing through the cell surface, and part of the light cannot be directly absorbed by the solar cell, thereby reducing the effective utilization of light energy. Especially when the lighting conditions are weak or the light incident angle is unfavorable, the shielding effect of the grid lines will be more significant. Summary of the invention

[0004] The utility model provides a sandwich grid line TOPCon solar cell structure to solve the problem in the prior art that the shielding of the front and back grid lines will affect the effective utilization of light energy.

[0005] In order to solve the above technical problems, the technical solution adopted by the utility model is:

[0006] A sandwich grid line TOPCon solar cell structure, comprising a first anti-reflection passivation layer group, a first aluminum oxide layer, a first velvet structure layer, a first PN junction layer, a phosphorus-containing silicon base layer, a tunneling silicon oxide layer, a phosphorus-doped polysilicon layer, a second anti-reflection passivation layer group, a first silicon oxynitride layer, a third anti-reflection passivation layer group, a first silicon nitride layer, a second aluminum oxide layer, a boron-containing silicon base layer, a second PN junction layer, a second velvet structure layer, a third aluminum oxide layer, and a fourth anti-reflection passivation layer group, which are sequentially arranged from top to bottom along a height direction;

[0007] Also included is a first electrode group and a second electrode group;

[0008] The first electrode group is disposed along a first horizontal direction through the phosphorus-doped polysilicon layer, the second anti-reflection passivation layer group, and the first silicon oxynitride layer;

[0009] The second electrode group is disposed along a first horizontal direction through the first silicon nitride layer, the third anti-reflection passivation layer group, and the first silicon oxynitride layer;

[0010] The first electrode group and the second electrode group are not in contact with each other and are parallel to each other.

[0011] Furthermore, the first electrode group includes a plurality of first electrodes arranged at equal intervals, the second electrode group includes a plurality of second electrodes arranged at equal intervals, and the plurality of first electrodes and the plurality of second electrodes are arranged alternately.

[0012] Furthermore, in a second horizontal direction, the orthographic projections of the first electrode group and the second electrode group partially overlap, and the second horizontal direction is perpendicular to the first horizontal direction.

[0013] Further, in the height direction, the orthographic projection of the first electrode partially overlaps with the adjacent second electrode.

[0014] Furthermore, the first anti-reflection passivation layer group has the same structure as the fourth anti-reflection passivation layer group and is arranged inversely in the height direction, and the first anti-reflection passivation layer group includes a second silicon nitride layer, a third silicon nitride layer, a fourth silicon nitride layer, a second silicon oxynitride layer, a third silicon oxynitride layer and a silicon dioxide layer arranged in sequence from top to bottom along the height direction.

[0015] Furthermore, the thickness of the second silicon nitride layer is 5.5 nm to 11.5 nm, and the refractive index is 2.25 to 2.31;

[0016] The thickness of the third silicon nitride layer is 11.5 nm to 17.5 nm, and the refractive index is 2.15 to 2.21;

[0017] The fourth silicon nitride layer has a thickness of 20 nm to 26 nm and a refractive index of 1.98 to 2.04;

[0018] The thickness of the second silicon oxynitride layer is 9 nm to 15 nm;

[0019] The thickness of the third silicon oxynitride layer is 7nm to 13nm;

[0020] The silicon dioxide layer has a thickness of 2 nm to 8 nm and a refractive index of 1.5.

[0021] Furthermore, the second anti-reflection passivation layer group has the same structure as the third anti-reflection passivation layer group and is arranged inversely in the height direction, and the second anti-reflection passivation layer group includes a fifth silicon nitride layer, a sixth silicon nitride layer and a seventh silicon nitride layer arranged in sequence from top to bottom along the height direction.

[0022] Further, the thickness of the fifth silicon nitride layer is 15nm to 21nm;

[0023] The thickness of the sixth silicon nitride layer is 15 nm to 21 nm;

[0024] The thickness of the seventh silicon nitride layer is 45 nm to 51 nm.

[0025] Furthermore, the thickness of the first aluminum oxide layer and the third aluminum oxide layer is 3 nm to 5 nm.

[0026] Furthermore, the first suede structure layer and the second suede structure layer are in a pyramid shape or a crater shape.

[0027] Due to the application of the above technical solution, the beneficial effects of the present application compared with the prior art are:

[0028] The present application provides a sandwich grid line TOPCon solar cell structure, which avoids blocking the battery by setting the first electrode group and the second electrode group inside the battery, so that light can directly enter the battery structure, and improves the efficiency of light energy utilization. At the same time, the double-sided PN junction design can make full use of long-wave light and short-wave light. In addition, a double-sided velvet structure layer is provided, which can be matched with different velvet structures to achieve absorption of direct light and diffuse reflection absorption. In addition, the first electrode group and the second electrode group pass through the inside of the battery respectively, so that they can be led out from the side surface of the battery structure, which facilitates the interconnection of the battery structure at the component end. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the specific implementation methods of the utility model or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0030] Figure 1 It is a schematic cross-sectional structure diagram of a sandwich grid line TOPCon solar cell structure according to an embodiment of the utility model.

[0031] Description of reference numerals:

[0032] 1-first anti-reflection passivation; 2-first aluminum oxide layer; 3-first velvet structure layer; 4-first PN junction layer; 5-phosphorus-containing silicon base layer; 6-tunneling silicon oxide layer; 7-phosphorus-doped polysilicon layer; 8-second anti-reflection passivation layer group; 9-first silicon oxynitride layer; 10-third anti-reflection passivation layer group; 11-first silicon nitride layer; 12-second aluminum oxide layer; 13-boron-containing silicon base layer; 14-second PN junction layer; 15-second velvet structure layer; 16-third aluminum oxide layer; 17-fourth anti-reflection passivation layer group; 18-first electrode; 19-second electrode. DETAILED DESCRIPTION

[0033] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present application.

[0034] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequential order. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present application described here. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0035] In this application, the terms "upper", "lower", "left", "right", "front", "back", "top", "bottom", "inner", "outer", "middle", "vertical", "horizontal", "lateral", "longitudinal" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings. These terms are mainly used to better describe the utility model and its embodiments, and are not used to limit the indicated devices, elements or components to have a specific orientation, or to be constructed and operated in a specific orientation.

[0036] In addition, some of the above terms may be used to express other meanings in addition to indicating orientation or positional relationship. For example, the term "on" may also be used to express a certain dependency or connection relationship in some cases. For those skilled in the art, the specific meanings of these terms in this utility model can be understood according to specific circumstances.

[0037] In addition, the terms "installed", "set", "provided with", "connected", "connected", and "socketed" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral structure; it can be a mechanical connection, or an electrical connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be an internal connection between two devices, elements, or components. For those of ordinary skill in the art, the specific meanings of the above terms in this utility model can be understood according to specific circumstances.

[0038] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0039] See also Figure 1 The embodiment of the utility model provides a sandwich grid line TOPCon solar cell structure, which includes a first anti-reflection passivation layer group 1, a first aluminum oxide layer 2, a first velvet structure layer 3, a first PN junction layer 4, a phosphorus-containing silicon base layer 5, a tunneling silicon oxide layer 6, a phosphorus-doped polysilicon layer 7, a second anti-reflection passivation layer group 8, a first silicon oxynitride layer 9, a third anti-reflection passivation layer group 10, a first silicon nitride layer 11, a second aluminum oxide layer 12, a boron-containing silicon base layer 13, a second PN junction layer 14, a second velvet structure layer 15, a third aluminum oxide layer 16, and a fourth anti-reflection passivation layer group 17, which are arranged in sequence from top to bottom along the height direction.

[0040] The battery structure also includes a first electrode group and a second electrode group. The first electrode group is arranged along the first horizontal direction through the phosphorus-doped polysilicon layer 7, the second anti-reflection passivation layer group 8, and the first silicon oxynitride layer 9. The second electrode group is arranged along the first horizontal direction through the first silicon nitride layer 11, the third anti-reflection passivation layer group 10, and the first silicon oxynitride layer 9. The first electrode group and the second electrode group are not in contact and are parallel to each other. As described above, the first electrode group and the second electrode group are separated by the first silicon oxynitride layer 9 to avoid short circuit.

[0041] In order to reduce the thickness of the battery, in this embodiment, the first electrode group includes a plurality of first electrodes 18 arranged at equal intervals, the second electrode group includes a plurality of second electrodes 19 arranged at equal intervals, and the plurality of first electrodes 18 and the plurality of second electrodes 19 are arranged alternately.

[0042] Specifically, in the second horizontal direction, the orthographic projections of the first electrode group and the second electrode group partially overlap, and the second horizontal direction is perpendicular to the first horizontal direction. In the height direction, the orthographic projections of the first electrode 18 and the adjacent second electrode 19 partially overlap.

[0043] In this embodiment, the first anti-reflection passivation layer group 1 has the same structure as the fourth anti-reflection passivation layer group 17 and is arranged inversely in the height direction. The first anti-reflection passivation layer group 1 includes a second silicon nitride layer (not shown), a third silicon nitride layer (not shown), a fourth silicon nitride layer (not shown), a second silicon oxynitride layer (not shown), a third silicon oxynitride layer (not shown), and a silicon dioxide layer (not shown) which are sequentially arranged from top to bottom in the height direction.

[0044] In detail, the thickness of the second silicon nitride layer is 5.5nm to 11.5nm, and the refractive index is 2.25 to 2.31. The thickness of the third silicon nitride layer is 11.5nm to 17.5nm, and the refractive index is 2.15 to 2.21. The thickness of the fourth silicon nitride layer is 20nm to 26nm, and the refractive index is 1.98 to 2.04. The thickness of the second silicon nitride oxide layer is 9nm to 15nm. The thickness of the third silicon nitride oxide layer is 7nm to 13nm. The thickness of the silicon dioxide layer is 2nm to 8nm, and the refractive index is 1.5.

[0045] In this embodiment, the second anti-reflection passivation layer group 8 has the same structure as the third anti-reflection passivation layer group 10 and is arranged inversely in the height direction. The second anti-reflection passivation layer group 8 includes a fifth silicon nitride layer (not shown), a sixth silicon nitride layer (not shown) and a seventh silicon nitride layer (not shown) which are sequentially arranged from top to bottom along the height direction.

[0046] In detail, the thickness of the fifth silicon nitride layer is 15 nm to 21 nm, the thickness of the sixth silicon nitride layer is 15 nm to 21 nm, and the thickness of the seventh silicon nitride layer is 45 nm to 51 nm.

[0047] In this embodiment, the thickness of the first aluminum oxide layer 2 and the third aluminum oxide layer 16 is 3 nm to 5 nm.

[0048] In this embodiment, the shapes of the first suede structure layer 3 and the second suede structure layer 15 are pyramid-shaped or crater-shaped, which is not specifically limited in the present application.

[0049] When in use, sunlight passes through the first anti-reflection passivation layer group 1 and the first aluminum oxide layer 2 in sequence before reaching the first velvet structure layer 3, generating front carriers in the first PN junction layer 4, and the front carriers pass through the phosphorus-containing silicon base layer 5, the tunneling silicon oxide layer 6, the phosphorus-doped polysilicon layer 7 and the second anti-reflection passivation layer group 8 in sequence, and are absorbed by the first electrode group and are led out from the side of the battery structure. Similarly, sunlight passes through the fourth anti-reflection passivation layer group 17 and the third aluminum oxide layer 16 in sequence before reaching the second velvet structure layer 15, generating back carriers in the second PN junction layer 14, and the back carriers pass through the boron-containing silicon base layer 13, the second aluminum oxide layer 12, the first silicon nitride layer 11 and the third anti-reflection passivation layer group 10 in sequence, and are absorbed by the second electrode group and are led out from the side of the battery structure. Among them, the front carriers are electrons and the back carriers are holes.

[0050] Due to the application of the above technical solution, the beneficial effects of the present application compared with the prior art are:

[0051] The present application provides a sandwich grid line TOPCon solar cell structure, which avoids blocking the battery by setting the first electrode group and the second electrode group inside the battery, so that light can directly enter the battery structure, and improves the efficiency of light energy utilization. At the same time, the double-sided PN junction design can make full use of long-wave light and short-wave light. In addition, a double-sided velvet structure layer is provided, which can be matched with different velvet structures to achieve absorption of direct light and diffuse reflection absorption. In addition, the first electrode group and the second electrode group pass through the inside of the battery respectively, so that they can be led out from the side surface of the battery structure, which facilitates the interconnection of the battery structure at the component end.

[0052] Finally, it should be noted that the above are only preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A sandwich grid line TOPCon solar cell structure, characterized in that: The invention comprises a first anti-reflection passivation layer group, a first aluminum oxide layer, a first textured structure layer, a first PN junction layer, a phosphorus-containing silicon base layer, a tunneling silicon oxide layer, a phosphorus-doped polysilicon layer, a second anti-reflection passivation layer group, a first silicon oxynitride layer, a third anti-reflection passivation layer group, a first silicon nitride layer, a second aluminum oxide layer, a boron-containing silicon base layer, a second PN junction layer, a second textured structure layer, a third aluminum oxide layer, and a fourth anti-reflection passivation layer group, which are sequentially arranged from top to bottom along the height direction; Also included is a first electrode group and a second electrode group; The first electrode group is disposed along a first horizontal direction through the phosphorus-doped polysilicon layer, the second anti-reflection passivation layer group, and the first silicon oxynitride layer; The second electrode group is disposed along a first horizontal direction through the first silicon nitride layer, the third anti-reflection passivation layer group, and the first silicon oxynitride layer; The first electrode group and the second electrode group are not in contact with each other and are parallel to each other.

2. A sandwich grid line TOPCon solar cell structure according to claim 1, characterized in that: The first electrode group includes a plurality of first electrodes arranged at equal intervals, the second electrode group includes a plurality of second electrodes arranged at equal intervals, and the plurality of first electrodes and the plurality of second electrodes are arranged alternately.

3. A sandwich grid line TOPCon solar cell structure according to claim 2, characterized in that: In a second horizontal direction, the orthographic projections of the first electrode group and the second electrode group partially overlap, and the second horizontal direction is perpendicular to the first horizontal direction.

4. A sandwich grid line TOPCon solar cell structure as claimed in claim 3, characterized in that: In the height direction, the first electrode partially overlaps with the orthographic projection of the adjacent second electrode.

5. The interlayer gridline TOPCon solar cell structure according to claim 1, characterized in that: The first anti-reflection passivation layer group has the same structure as the fourth anti-reflection passivation layer group and is arranged inversely in the height direction. The first anti-reflection passivation layer group includes a second silicon nitride layer, a third silicon nitride layer, a fourth silicon nitride layer, a second silicon oxynitride layer, a third silicon oxynitride layer and a silicon dioxide layer arranged in sequence from top to bottom along the height direction.

6. A sandwich grid line TOPCon solar cell structure as claimed in claim 5, characterized in that: The second silicon nitride layer has a thickness of 5.5 nm to 11.5 nm and a refractive index of 2.25 to 2.31; The thickness of the third silicon nitride layer is 11.5 nm to 17.5 nm, and the refractive index is 2.15 to 2.21; The fourth silicon nitride layer has a thickness of 20 nm to 26 nm and a refractive index of 1.98 to 2.04; The thickness of the second silicon oxynitride layer is 9 nm to 15 nm; The thickness of the third silicon oxynitride layer is 7nm to 13nm; The silicon dioxide layer has a thickness of 2 nm to 8 nm and a refractive index of 1.

5.

7. The interlayer gridline TOPCon solar cell structure according to claim 1, characterized in that: The second anti-reflection passivation layer group has the same structure as the third anti-reflection passivation layer group and is arranged inversely in the height direction. The second anti-reflection passivation layer group includes a fifth silicon nitride layer, a sixth silicon nitride layer and a seventh silicon nitride layer arranged in sequence from top to bottom in the height direction.

8. The interlayer gridline TOPCon solar cell structure according to claim 7, characterized in that: The thickness of the fifth silicon nitride layer is 15nm to 21nm; The thickness of the sixth silicon nitride layer is 15 nm to 21 nm; The thickness of the seventh silicon nitride layer is 45 nm to 51 nm.

9. The interlayer gridline TOPCon solar cell structure according to claim 1, characterized in that: The thickness of the first aluminum oxide layer and the third aluminum oxide layer is 3 nm to 5 nm.

10. The interlayer gridline TOPCon solar cell structure according to claim 1, characterized in that: The first suede structure layer and the second suede structure layer are in a pyramid shape or a crater shape.

Images