UTG-based solar cell substrate and solar cell

Abstract

The application relates to a UTG-based solar cell substrate and a solar cell. The UTG-based solar cell substrate comprises a connecting layer, a first UTG substrate layer, a growth substrate layer and an epitaxial growth layer. The connecting layer is arranged on one side of the first UTG substrate layer. The growth substrate layer is arranged on the side, away from the connecting layer, of the first UTG substrate layer. The growth substrate layer comprises at least one of a copper layer, an iridium layer, a hexagonal boron nitride layer and a silicon carbide layer, and the epitaxial growth layer comprises a graphene layer arranged on the side, away from the first UTG substrate layer, of the growth substrate layer. The UTG substrate layer has excellent characteristics such as high light transmittance, high barrier property, atomic oxygen resistance, radiation resistance and bendability. The growth substrate layer has good heat conduction performance. The graphene layer can be epitaxially grown on the growth substrate layer easily, and the graphene layer has high infrared emission performance and high conductivity, can realize passive and efficient heat dissipation, avoid accumulation of static electricity, and prevent the internal circuit of the battery from being broken.

Description

Technical Field

[0001] This application relates to the field of photovoltaic technology, and in particular to a UTG-based solar cell substrate and a solar cell. Background Technology

[0002] With the rapid development of aerospace technology, high-power, lightweight, and extreme-environment-resistant flexible solar cells have become a core development direction for spacecraft energy systems. Traditional space solar cells mostly use rigid glass covers or polymer substrates. Rigid glass is heavy, brittle, and inflexible, making it difficult to meet the lightweight and curved integration requirements of spacecraft. Although polymer substrates (such as polyimide) are lightweight and flexible, they are prone to aging and degradation under the strong radiation, single-atom oxygen corrosion, and severe thermal cycling environments of space, resulting in rapid performance degradation and failing to meet the requirements for long-life service.

[0003] Ultra-thin glass (UTG) combines the high light transmittance, high barrier properties, and excellent flexibility of glass, overcoming the shortcomings of rigid glass covers and polymer substrates. However, UTG still has the following drawbacks: First, when solar cells are exposed to strong solar radiation in sunny areas, heat accumulates rapidly, leading to decreased photoelectric conversion efficiency, shortened lifespan, and reduced reliability. Second, during on-orbit operation, electrostatic charges easily accumulate on the surface of the battery, which can easily trigger electrostatic discharge and circuit breakdown, seriously threatening the safe and stable operation of the battery. Utility Model Content

[0004] Therefore, it is necessary to provide a UTG-based solar cell substrate and solar cell to solve the problems of heat accumulation and electrostatic charge buildup.

[0005] A UTG-based solar cell substrate includes a connecting layer, a first UTG substrate layer, a growth substrate layer, and an epitaxial growth layer. The connecting layer is disposed on one side of the first UTG substrate layer, and the growth substrate layer is disposed on the side of the first UTG substrate layer opposite to the connecting layer. The growth substrate layer includes at least one layer selected from copper, iridium, hexagonal boron nitride, and silicon carbide. When the growth substrate layer includes multiple layers selected from the above, the multiple layers are stacked. The epitaxial growth layer is disposed on the side of the growth substrate layer opposite to the first UTG substrate layer, and the epitaxial growth layer includes a graphene layer.

[0006] In some embodiments, at least one side of the first UTG substrate layer has a nano-uneven surface structure.

[0007] In some embodiments, the bonding layer includes an optical adhesive layer.

[0008] In some embodiments, the thickness of the first UTG substrate layer is 30 μm to 80 μm.

[0009] In some embodiments, the transmittance of the first UTG substrate layer is greater than 90%.

[0010] In some embodiments, the thickness of the growth substrate layer is 20 nm to 50 nm.

[0011] In some embodiments, the thickness of the epitaxial growth layer is 0.3 nm to 2 nm.

[0012] A solar cell includes a UTG-based solar cell substrate, a cell body, and a second UTG substrate layer as described in any of the above embodiments. The cell body is disposed between the UTG-based solar cell substrate and the second UTG substrate layer, and the UTG-based solar cell substrate is connected to the cell body through the connecting layer.

[0013] In some embodiments, the battery body includes a first electrode layer, an electron conduction layer, a light absorption layer, a hole conduction layer, and a second electrode layer stacked sequentially, wherein the first electrode layer is connected to the second UTG substrate layer, and the second electrode layer is connected to the connecting layer.

[0014] In some embodiments, the solar cell further includes an antireflection layer disposed on the side of the second UTG substrate layer opposite to the cell body.

[0015] In some embodiments, the antireflection layer includes at least one stacked unit, the stacked unit including a first refractive index sublayer, a second refractive index sublayer and a third refractive index sublayer, the refractive indices of the first refractive index sublayer, the second refractive index sublayer and the third refractive index sublayer decreasing sequentially, and in the same stacked unit, the first refractive index sublayer is closer to the battery body than the second refractive index sublayer; when the antireflection layer includes multiple stacked units, the multiple stacked units are stacked.

[0016] In some embodiments, the first refractive index sublayer is a TiO2 layer, a ZrO2 layer, a HfO2 layer, a ZnO layer, a Ta2O5 layer, a CeO2 layer, a ZnS layer, or a Nb2O5 layer.

[0017] In some embodiments, the second refractive index sublayer is a Si3N4 layer, a SiAlON layer, or an AlON layer.

[0018] In some embodiments, the third refractive index sublayer is a SiO2 layer, a MgF2 layer, or an Al2O3 layer.

[0019] In some embodiments, the solar cell further includes a grid-like ITO layer disposed on the side of the antireflective layer opposite to the second UTG substrate layer.

[0020] Compared with traditional technologies, the above-mentioned UTG-based solar cell substrate and solar cell have the following advantages:

[0021] The aforementioned UTG-based solar cell substrate uses a first UTG substrate layer as the core support structure, which possesses excellent properties such as high light transmittance, high barrier properties, resistance to atomic oxygen, radiation resistance, and bendability. A connecting layer is used to connect the cell body. The growth substrate layer includes at least one of a copper layer, an iridium layer, a hexagonal boron nitride layer, and a silicon carbide layer. The epitaxial growth layer includes a graphene layer. The graphene layer can be easily epitaxially grown on the aforementioned growth substrate layer, exhibiting high lattice matching, a complete structure, low defect density, and excellent electrical and thermal properties. The copper and iridium layers possess extremely high thermal conductivity, enabling rapid heat conduction. The hexagonal boron nitride and silicon carbide layers combine high thermal conductivity with high infrared emission performance, allowing for heat dissipation through infrared radiation. They also possess excellent chemical stability, resistance to atomic oxygen and space radiation, making them suitable for the extreme environment of space. The graphene layer combines high infrared emission performance with high electrical conductivity. Its high infrared emission performance enables it to rapidly dissipate the heat conducted by the substrate layer into the external environment in the form of infrared radiation, achieving passive and efficient heat dissipation and reducing the battery's operating temperature. Its high conductivity allows it to quickly dissipate the electrostatic charge accumulated on the battery surface in the space plasma environment, preventing charge accumulation that could lead to electrostatic discharge, thus preventing damage to the internal circuitry and improving the battery's operational safety and reliability.

[0022] The solar cells described above have UTG-based solar cell substrates according to any of the above embodiments, and therefore have corresponding technical features and can obtain corresponding beneficial effects. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the structure of a UTG-based solar cell substrate according to an embodiment;

[0024] Figure 2 For inclusion Figure 1 The diagram shows the structure of a solar cell on a UTG-based solar cell substrate.

[0025] Explanation of reference numerals in the attached figures:

[0026] 100, UTG-based solar cell substrate; 110, Connecting layer; 120, First UTG substrate layer; 130, Growth substrate layer; 140, Epitaxial growth layer; 20, Solar cell; 200, Cell body; 210, First electrode layer; 220, Electron conduction layer; 230, Light-absorbing layer; 240, Hole conduction layer; 250, Second electrode layer; 300, Second UTG substrate layer; 400, Anti-reflection layer; 410, First refractive index sublayer; 420, Second refractive index sublayer; 430, Third refractive index sublayer; 500, Mesh-like ITO layer. Detailed Implementation

[0027] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0028] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0029] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0030] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0031] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0032] like Figure 1 As shown, a UTG-based solar cell substrate 100 of one embodiment includes a connecting layer 110, a first UTG substrate layer 120, a growth substrate layer 130, and an epitaxial growth layer 140. The connecting layer 110 is disposed on one side of the first UTG substrate layer 120. The growth substrate layer 130 is disposed on the side of the first UTG substrate layer 120 opposite to the connecting layer 110. The growth substrate layer 130 includes at least one layer selected from copper, iridium, hexagonal boron nitride, and silicon carbide. When the growth substrate layer 130 includes multiple layers selected from the above, the multiple layers are stacked. The epitaxial growth layer 140 is disposed on the side of the growth substrate layer 130 opposite to the first UTG substrate layer 120. The epitaxial growth layer 140 includes a graphene layer.

[0033] The first UTG substrate layer 120 serves as the core support structure. The material is UTG (ultra-thin flexible glass), which has excellent properties such as high light transmittance, high barrier properties, resistance to atomic oxygen, radiation resistance, and bendability.

[0034] In some examples, the thickness of the first UTG substrate layer 120 is 30 μm to 80 μm. In some specific examples, the thickness of the first UTG substrate layer 120 is, for example, 30 μm, 35 μm, 40 μm, 45 μm, 50 μm, 55 μm, 60 μm, 65 μm, 70 μm, 75 μm, 80 μm, etc.

[0035] The first UTG substrate layer 120 has a light transmittance greater than 90%. For example, the light transmittance of the first UTG substrate layer 120 is 90% to 99%. High light transmittance can reduce light absorption and reflection loss, allowing incident light to pass through efficiently and improving the photoelectric conversion efficiency of the battery.

[0036] In some examples, at least one side of the first UTG substrate layer 120 has a nano-uneven surface structure. The nano-uneven surface structure can be formed by plasma treatment of the surface of the first UTG substrate layer 120. Plasma treatment can form a uniform nanoscale uneven morphology on the surface of the first UTG substrate layer 120, significantly improving surface roughness and surface energy, enhancing the interfacial adhesion between the first UTG substrate layer 120 and the connecting layer 110 and the growth substrate layer 130, avoiding problems such as film peeling and cracking, and improving the stability and durability of the substrate structure. In some examples, both sides of the first UTG substrate layer 120 have nano-uneven surface structures.

[0037] The growth substrate layer 130 is disposed on the side of the first UTG substrate layer 120 opposite to the connecting layer 110, and includes at least one layer selected from copper, iridium, hexagonal boron nitride, and silicon carbide. Graphene can be easily epitaxially grown on the aforementioned growth substrate layer 130, exhibiting high lattice matching, complete structure, low defect density, and excellent electrical and thermal properties. The copper and iridium layers possess extremely high thermal conductivity, enabling rapid heat conduction. The hexagonal boron nitride and silicon carbide layers combine high thermal conductivity with high infrared emission performance, enabling heat dissipation through infrared radiation, while also demonstrating excellent chemical stability, resistance to atomic oxygen and space radiation, making them suitable for the extreme environment of space.

[0038] In some examples, the thickness of the substrate layer 130 is 20nm to 50nm. In some specific examples, the thickness of the substrate layer 130 is, for example, 20nm, 25nm, 30nm, 35nm, 40nm, 45nm, 50nm, etc. Controlling the thickness of the substrate layer 130 within the above range ensures thermal conductivity while avoiding excessive thickness that would increase the overall weight of the substrate and optical loss, thus maintaining the flexibility of the substrate.

[0039] An epitaxial growth layer 140 is disposed on the side of the growth substrate layer 130 opposite to the first UTG substrate layer 120. The epitaxial growth layer 140 includes a graphene layer. The graphene is formed on the surface of the growth substrate layer 130 by epitaxial growth, exhibiting high lattice matching, complete structure, low defect density, and excellent electrical and thermal properties.

[0040] In some examples, the thickness of the epitaxial growth layer 140 is 0.3 nm to 2 nm. In some specific examples, the thickness of the epitaxial growth layer 140 is, for example, 0.3 nm, 0.5 nm, 0.8 nm, 1.0 nm, 1.2 nm, 1.5 nm, 1.8 nm, 2 nm, etc. The graphene layer is a single-layer or few-layer structure with extremely thin thickness, which does not increase the overall thickness and weight of the substrate, while maintaining high flexibility.

[0041] The graphene layer possesses both high infrared emission and high conductivity. Its high infrared emission allows it to rapidly dissipate heat conducted by the substrate layer 130 into the external environment via infrared radiation, achieving passive and efficient heat dissipation and reducing battery operating temperature. Its high conductivity enables it to quickly dissipate electrostatic charges accumulated on the battery surface in the space plasma environment, preventing charge buildup that could lead to electrostatic discharge, thus preventing damage to the internal circuitry and improving battery safety and reliability.

[0042] In some of these examples, the bonding layer 110 includes an optical adhesive layer, such as an OCA layer.

[0043] The aforementioned UTG-based solar cell substrate 100 employs a first UTG substrate layer 120 as its core support structure, possessing excellent properties such as high light transmittance, high barrier properties, resistance to atomic oxygen, radiation resistance, and bendability. A connecting layer 110 is used to connect the cell body. The growth substrate layer 130 includes at least one of a copper layer, an iridium layer, a hexagonal boron nitride layer, and a silicon carbide layer. The epitaxial growth layer 140 includes a graphene layer, which can be easily epitaxially grown on the aforementioned growth substrate layer 130. The copper and iridium layers possess extremely high thermal conductivity, enabling rapid heat conduction. The hexagonal boron nitride and silicon carbide layers combine high thermal conductivity with high infrared emission performance, allowing for heat dissipation through infrared radiation. They also exhibit excellent chemical stability, resistance to atomic oxygen and space radiation, making them suitable for the extreme environment of space. The graphene layer combines high infrared emission performance with high electrical conductivity. Its high infrared emission performance enables it to rapidly dissipate the heat conducted by the substrate layer 130 to the external environment in the form of infrared radiation, achieving passive and efficient heat dissipation and reducing the battery's operating temperature. Its high conductivity allows it to quickly dissipate the electrostatic charge accumulated on the battery surface in the space plasma environment, preventing charge accumulation from causing electrostatic discharge, preventing damage to the internal circuitry of the battery, and improving the battery's operational safety and reliability.

[0044] Furthermore, this application also provides a solar cell.

[0045] like Figure 2 As shown, one embodiment of the solar cell 20 includes a UTG-based solar cell substrate 100, a cell body 200, and a second UTG substrate layer 300, as described in any of the above examples. The cell body 200 is disposed between the UTG-based solar cell substrate 100 and the second UTG substrate layer 300. The UTG-based solar cell substrate 100 is connected to the cell body 200 via a connecting layer 110.

[0046] In some examples, the thickness of the second UTG substrate layer 300 is 30 μm to 80 μm. In some specific examples, the thickness of the second UTG substrate layer 300 is, for example, 30 μm, 35 μm, 40 μm, 45 μm, 50 μm, 55 μm, 60 μm, 65 μm, 70 μm, 75 μm, 80 μm, etc.

[0047] In some of these examples, the light transmittance of the second UTG substrate layer 300 is greater than 90%. For example, the light transmittance of the second UTG substrate layer 300 is 90% to 99%.

[0048] In some examples, the battery body 200 includes a first electrode layer 210, an electron-conducting layer 220, a light-absorbing layer 230, a hole-conducting layer 240, and a second electrode layer 250, which are stacked sequentially. The first electrode layer 210 is connected to the second UTG substrate layer 300. The second electrode layer 250 is connected to the connecting layer 110.

[0049] In some examples, the first electrode layer 210 is an indium tin oxide (ITO) layer, an aluminum zinc oxide (AZO) layer, a zinc gallium oxide (GZO) layer, or an indium gallium zinc oxide (IGZO) layer. During on-orbit operation, the surface of the solar cell 20 is prone to charge accumulation, which may trigger electrostatic discharge and break down the cell circuitry. The first electrode layer 210 made of the aforementioned materials can effectively release the accumulated charge without affecting transmittance. In some examples, the thickness of the first electrode layer 210 is 20 nm to 100 nm.

[0050] In some of these examples, the electron conduction layer 220 is a SnO2 layer, a TiO2 layer, or a ZnO layer.

[0051] In some of these examples, the light-absorbing layer 230 is a perovskite material layer.

[0052] In some of these examples, the hole-conducting layer 240 is a CuCrO2 layer, a NiO layer, or a WO3 layer.

[0053] In some examples, the second electrode layer 250 is an Ag layer, an Al layer, or a Mo layer. The second electrode layer 250 of the above materials exhibits excellent conductivity and light reflection properties.

[0054] In some examples, the solar cell 20 also includes an antireflective layer 400. The antireflective layer 400 is disposed on the side of the second UTG substrate layer 300 opposite to the cell body 200.

[0055] In some examples, the antireflective layer 400 includes at least one stacked unit, which includes a first refractive index sublayer 410, a second refractive index sublayer 420, and a third refractive index sublayer 430. The refractive indices of the first refractive index sublayer 410, the second refractive index sublayer 420, and the third refractive index sublayer 430 decrease sequentially. Within the same stacked unit, the first refractive index sublayer 410 is closer to the battery body 200 than the second refractive index sublayer 420. When the antireflective layer 400 includes multiple stacked units, the multiple stacked units are arranged in a stacked manner.

[0056] In some of these examples, the refractive index of the first refractive index sublayer 410 is 1.9 to 2.4.

[0057] In some of these examples, the thickness of the first refractive index sublayer 410 is 110 nm to 150 nm, specifically 110 nm, 120 nm, 130 nm, 140 nm, 150 nm, etc.

[0058] In some of these examples, the first refractive index sublayer 410 is a TiO2 layer, a ZrO2 layer, a HfO2 layer, a ZnO layer, a Ta2O5 layer, a CeO2 layer, a ZnS layer, or a Nb2O5 layer.

[0059] In some of these examples, the first refractive index sublayer 410 was fabricated using magnetron sputtering. The fabrication process parameters included: first, evacuating the cavity to a vacuum of 2 × 10⁻⁶. -5 Pa ~ 8×10 -5 Pa, with an Ar flow rate of 20 sccm to 100 sccm, using radio frequency (RF) mode, operating gas pressure of 0.1 Pa to 1 Pa, and power of 20 W to 60 W.

[0060] In some of these examples, the refractive index of the second refractive index sublayer 420 is 1.8 to 2.2.

[0061] In some of these examples, the thickness of the second refractive index sublayer 420 is 110 nm to 150 nm, specifically 110 nm, 120 nm, 130 nm, 140 nm, 150 nm, etc.

[0062] In some examples, the second refractive index sublayer 420 is a Si3N4 layer, a SiAlON layer, or an AlON layer. The second refractive index sublayer 420 of the above materials possesses high hardness, high density, and good interfacial compatibility.

[0063] In some of these examples, the second refractive index sublayer 420 was fabricated using magnetron sputtering. The fabrication process parameters included: first, evacuating the cavity to a vacuum of 2 × 10⁻⁶. -5 Pa ~ 8×10 -5 Pa, with an Ar flow rate of 20 sccm to 100 sccm, using radio frequency (RF) mode, operating gas pressure of 0.1 Pa to 1 Pa, and power of 20 W to 60 W.

[0064] In some of these examples, the refractive index of the third refractive index sublayer 430 is between 1.4 and 1.7.

[0065] In some of these examples, the thickness of the third refractive index sublayer 430 is 110 nm to 150 nm, specifically 110 nm, 120 nm, 130 nm, 140 nm, 150 nm, etc.

[0066] In some examples, the third refractive index sublayer 430 is a SiO2 layer, a MgF2 layer, or an Al2O3 layer. The third refractive index sublayer 430 of the above materials has the characteristics of low refractive index, high transmittance, and high stability.

[0067] In some of these examples, the third refractive index sublayer 430 was fabricated using magnetron sputtering. The fabrication process parameters included: first, evacuating the cavity to a vacuum of 2 × 10⁻⁶. -5 Pa ~ 8×10 -5Pa, with an Ar flow rate of 20 sccm to 100 sccm, using radio frequency (RF) mode, operating gas pressure of 0.1 Pa to 1 Pa, and power of 20 W to 60 W.

[0068] The aforementioned antireflection layer 400 can reduce interface light reflection loss and improve light transmittance. It also has functions such as blocking single-atom oxygen penetration and resisting space particle impact, thereby improving the battery's durability in the space environment.

[0069] In some examples, the solar cell 20 also includes a grid-like ITO layer 500. The grid-like ITO layer 500 is disposed on the side of the antireflective layer 400 opposite to the second UTG substrate layer 300.

[0070] The aforementioned mesh-like ITO layer 500 has high conductivity and high light transmittance, which can enhance the surface charge conduction ability, quickly release static charge, avoid electrostatic discharge damage, and at the same time, the mesh structure does not significantly reduce light transmittance, thus ensuring the optical performance of the battery.

[0071] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0072] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the utility model patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims, and the specification can be used to interpret the content of the claims.

Claims

1. A UTG-based solar cell substrate, characterized in that, The system includes a connecting layer, a first UTG substrate layer, a growth substrate layer, and an epitaxial growth layer. The connecting layer is disposed on one side of the first UTG substrate layer, and the growth substrate layer is disposed on the side of the first UTG substrate layer opposite to the connecting layer. The growth substrate layer includes at least one layer selected from copper, iridium, hexagonal boron nitride, and silicon carbide. When the growth substrate layer includes multiple layers selected from the above, the multiple layers are stacked. The epitaxial growth layer is disposed on the side of the growth substrate layer opposite to the first UTG substrate layer, and the epitaxial growth layer includes a graphene layer.

2. The UTG-based solar cell substrate as described in claim 1, characterized in that, The UTG-based solar cell substrate meets at least one of the following characteristics (1) to (2): (1) At least one side of the first UTG substrate layer has a nano-uneven surface structure; (2) The bonding layer includes an optical adhesive layer.

3. The UTG-based solar cell substrate as described in claim 1, characterized in that, The UTG-based solar cell substrate meets at least one of the following characteristics (1) to (2): (1) The thickness of the first UTG substrate layer is 30μm~80μm; (2) The light transmittance of the first UTG substrate layer is greater than 90%.

4. The UTG-based solar cell substrate according to any one of claims 1 to 3, characterized in that, The UTG-based solar cell substrate meets at least one of the following characteristics (1) to (2): (1) The thickness of the growth substrate layer is 20nm~50nm; (2) The thickness of the epitaxial growth layer is 0.3nm~2nm.

5. A solar cell, characterized in that, The device includes a UTG-based solar cell substrate, a battery body, and a second UTG substrate layer as described in any one of claims 1 to 4. The battery body is disposed between the UTG-based solar cell substrate and the second UTG substrate layer, and the UTG-based solar cell substrate is connected to the battery body through the connecting layer.

6. The solar cell as described in claim 5, characterized in that, The battery body includes a first electrode layer, an electron conduction layer, a light absorption layer, a hole conduction layer, and a second electrode layer stacked in sequence. The first electrode layer is connected to the second UTG substrate layer, and the second electrode layer is connected to the connecting layer.

7. The solar cell as described in claim 5, characterized in that, The solar cell further includes an anti-reflection layer disposed on the side of the second UTG substrate layer opposite to the main body of the cell.

8. The solar cell as claimed in claim 7, characterized in that, The antireflection layer includes at least one stacked unit, which includes a first refractive index sublayer, a second refractive index sublayer, and a third refractive index sublayer. The refractive indices of the first, second, and third refractive index sublayers decrease sequentially. Within the same stacked unit, the first refractive index sublayer is closer to the battery body than the second refractive index sublayer. When the antireflection layer includes multiple stacked units, the multiple stacked units are stacked on top of each other.

9. The solar cell as claimed in claim 8, characterized in that, The solar cell meets at least one of the following characteristics (1) to (3): (1) The first refractive index sublayer is a TiO2 layer, ZrO2 layer, HfO2 layer, ZnO layer, Ta2O5 layer, CeO2 layer, ZnS layer or Nb2O5 layer; (2) The second refractive index sublayer is a Si3N4 layer, a SiAlON layer, or an AlON layer; (3) The third refractive index sublayer is a SiO2 layer, a MgF2 layer or an Al2O3 layer.

10. The solar cell according to any one of claims 7 to 9, characterized in that, The solar cell further includes a grid-like ITO layer disposed on the side of the antireflective layer opposite to the second UTG substrate layer.

Images