Double-sided passivation contact crystalline silicon solar cell and preparation method thereof

Abstract

The invention belongs to the technical field of solar cells, and particularly discloses a double-sided passivation contact crystalline silicon solar cell and a preparation method thereof.The double-sided passivation contact crystalline silicon solar cell comprises an n-type monocrystalline silicon substrate, a boron-doped emitter layer, a first passivation layer, a first transmission layer, a sacrificial layer and a first antireflection layer, and a grid-line-shaped first metal electrode is arranged on the upper end face of the first antireflection layer; the tail end of the first metal electrode sequentially penetrates through the first antireflection layer and the sacrificial layer to be in contact with the upper end surface of the first transmission layer; a second passivation layer, a second transmission layer and a second antireflection layer are sequentially arranged on the lower end face of the n-type monocrystalline silicon substrate from top to bottom, and a grid-line-shaped second metal electrode is arranged on the lower end face of the second antireflection layer. Passivation contact structures are achieved on the front face and the back face of the cell, the surface passivation effect of the cell is improved, meanwhile, the optical parasitic absorption problem of the cell is solved, the open-circuit voltage and the short-circuit current of the cell are effectively improved, and then the photoelectric conversion efficiency of the cell is improved.

Description

Technical Field

[0001] The invention relates to the technical field of solar cells, in particular to a double-sided passivated contact crystalline silicon solar cell and a preparation method thereof. Background Art

[0002] At present, the mainstream cell structure of the silicon-based photovoltaic industry, PERC cells (Passivated Emitter and RearSolar Cell), has achieved mature industrial production. However, the compound loss caused by the direct contact between the metal electrode on the back of this structure and silicon leads to its theoretical limit efficiency of about 24.5%, which limits the further development of this cell structure. Therefore, people have deepened the technology based on PERC cells and developed TOPCon cells (Tunnel Oxide Passivated Contact Solar Cell). This cell uses the same selective emitter structure as the PERC cell on the front surface, prepares an ultra-thin tunnel oxide layer on the back of the cell, and then deposits a layer of doped polysilicon to form a passivation contact structure, which provides good full-area passivation for the back of the silicon wafer and improves the conversion efficiency of the cell. This structural design can bend the energy band on the surface of the silicon wafer, greatly increase the probability of electron tunneling, reduce the contact resistance, and improve the open circuit voltage and fill factor of the cell, thereby improving the cell conversion efficiency.

[0003] At present, there is still a certain distance between the highest efficiency of industrialized n-type TOPCon cells and their potential efficiency. On the one hand, the front of the cell has the same defects as the PERC cell, that is, the serious composite loss caused by the direct contact between the metal and the silicon substrate, which reduces the open circuit voltage and fill factor of the cell. At the same time, the higher contact resistance will increase the series resistance of the cell, affecting the further improvement of the cell efficiency. On the other hand, the phosphorus-doped polysilicon (poly-Si) on the back of the cell has serious optical parasitic absorption of short-wave sunlight, which limits the short-circuit current density of the cell. To reduce optical losses, one solution is to thin the polysilicon layer, but it will face the problem of burn-through during the electrode sintering process. In addition, the high-temperature crystallization process of poly-Si (>800°C) not only increases the manufacturing cost, but may also cause thermal damage to other parts of the cell.

[0004] Therefore, it is urgent to develop a low-cost double-sided passivated contact crystalline silicon solar cell. Summary of the invention

[0005] In order to solve the above technical problems, the present invention provides a double-sided passivated contact crystalline silicon solar cell and a preparation method thereof, in which a passivated contact structure is realized on both the front and back sides of the cell, thereby improving the surface passivation effect of the cell and improving the optical parasitic absorption problem of the cell, effectively improving the open circuit voltage and short circuit current of the cell, thereby facilitating the improvement of the photoelectric conversion efficiency of the cell.

[0006] To achieve the above object, the present invention is implemented according to the following technical solutions:

[0007] The first technical solution provided by the present invention is a double-sided passivated contact crystalline silicon solar cell, comprising an n-type single crystal silicon substrate, wherein the upper end surface of the n-type single crystal silicon substrate is provided with a boron-doped emitter layer, a first passivation layer, a first transmission layer, a sacrificial layer and a first anti-reflection layer in sequence from bottom to top, the upper end surface of the first anti-reflection layer is provided with a first gate-line-shaped metal electrode, and the end of the first metal electrode sequentially penetrates the first anti-reflection layer and the sacrificial layer and contacts the upper end surface of the first transmission layer; the lower end surface of the n-type single crystal silicon substrate is provided with a second passivation layer, a second transmission layer and a second anti-reflection layer in sequence from top to bottom, and the lower end surface of the second anti-reflection layer is provided with a second gate-line-shaped metal electrode.

[0008] Furthermore, the material of the boron-doped emitter layer is boron-doped single crystal silicon, the diffusion sheet resistance of the boron-doped emitter layer is 100-300Ω / Sq, and the surface concentration is 8×10 19 -1×10 20 atoms / cm 3 The doping junction depth is 0.1~0.8μm.

[0009] Furthermore, the material of the first passivation layer is silicon oxide, and the thickness of the first passivation layer is 0.5-2.5 nm.

[0010] Furthermore, the material of the first transmission layer is one or more of aluminum-doped zinc oxide, boron-doped zinc oxide and gallium-doped zinc oxide, and the thickness of the first transmission layer is 3-80 nm.

[0011] Furthermore, the material of the sacrificial layer is aluminum oxide or silicon nitride, and the thickness of the sacrificial layer is 10-50 nm.

[0012] Furthermore, the material of the first anti-reflection layer is one or more of aluminum oxide, silicon nitride, hydrogenated silicon nitride and magnesium fluoride, and the thickness of the first anti-reflection layer is 20-200 nm.

[0013] Furthermore, the material of the second passivation layer is silicon oxide or intrinsic hydrogenated amorphous silicon, and the thickness of the second passivation layer is 1-10 nm.

[0014] Furthermore, the material of the second transmission layer is one of phosphorus-doped polysilicon, phosphorus-doped hydrogenated amorphous silicon and doped zinc oxide, and the thickness of the second transmission layer is 3-80 nm.

[0015] Furthermore, the material of the second anti-reflection layer is one or more of tin-doped indium oxide, fluorine-doped tin oxide, aluminum-doped zinc oxide and indium-doped zinc oxide, and the thickness of the second anti-reflection layer is 20-200 nm.

[0016] The second technical solution provided by the present invention is a method for preparing a double-sided passivated contact crystalline silicon solar cell, comprising the following steps:

[0017] S1, pre-cleaning and alkali texturing treatment of n-type single crystal silicon substrate;

[0018] S2, performing boron diffusion on the upper end surface of the n-type single crystal silicon substrate, the diffusion temperature is 900-1100° C., and the time is 15-30 minutes, so that the upper end surface of the n-type single crystal silicon substrate is formed into a boron-doped emitter layer;

[0019] S3, forming a first passivation layer on the upper end surface of the boron-doped emitter layer; the first passivation layer can be prepared by using one of conventional ultraviolet / ozone oxidation method, oxygen plasma treatment method, thermal oxidation method and wet oxidation method;

[0020] S4, forming a first transmission layer on the upper end surface of the first passivation layer; the first transmission layer can be prepared by using one of conventional atomic layer deposition, magnetron sputtering, chemical vapor deposition, pulsed laser deposition, and thermal evaporation methods;

[0021] S5. Forming a sacrificial layer on the upper end surface of the first transmission layer; the sacrificial layer can be prepared by conventional atomic layer deposition, magnetron sputtering, plasma enhanced chemical vapor deposition and low pressure chemical vapor deposition; and annealing in a forming gas atmosphere composed of nitrogen and hydrogen in a volume ratio of 95%:5%, the annealing temperature is 400-550° C., and the annealing time is 10-60 min;

[0022] S6, forming a first anti-reflection layer on the upper end surface of the sacrificial layer; the first anti-reflection layer can be prepared by using one of conventional plasma enhanced chemical vapor deposition, atomic layer deposition, magnetron sputtering and thermal evaporation methods;

[0023] S7, forming a first metal electrode on the first anti-reflection layer, penetrating the first anti-reflection layer and the sacrificial layer and contacting the upper end surface of the first transmission layer; the first metal electrode can be an aluminum electrode; specifically, wet etching or laser patterning of the first anti-reflection layer and the sacrificial layer to remove part of the sacrificial layer and part of the first anti-reflection layer above the first transmission layer, and then screen printing a metal grid line on the upper end surface of the first transmission layer, and high-temperature sintering in a forming gas atmosphere composed of nitrogen and hydrogen in a volume ratio of 95%:5% to prepare the first metal electrode, the high-temperature sintering temperature is 500-800°C, and the sintering time is 10-40min;

[0024] S8, forming a second passivation layer on the lower end surface of the n-type single crystal silicon substrate; when the second passivation layer is silicon oxide, the second passivation layer can be prepared by one of conventional ultraviolet / ozone oxidation, oxygen plasma treatment, thermal oxidation and wet oxidation methods; when the second passivation layer is intrinsic hydrogenated amorphous silicon, the second passivation layer can be prepared by one of conventional plasma enhanced chemical vapor deposition, hot wire chemical vapor deposition, microwave electron cyclotron resonance chemical vapor deposition and magnetron sputtering;

[0025] S9. Forming a second transmission layer on the lower end surface of the second passivation layer; when the second transmission layer is phosphorus-doped polycrystalline silicon, the second transmission layer can be prepared by one of conventional plasma enhanced chemical vapor deposition, low pressure chemical vapor deposition and hot wire chemical vapor deposition; when the second transmission layer is phosphorus-doped hydrogenated amorphous silicon, the second transmission layer can be prepared by one of conventional plasma enhanced chemical vapor deposition, hot wire chemical vapor deposition, microwave electron cyclotron resonance chemical vapor deposition and magnetron sputtering; when the second transmission layer is doped zinc oxide, the second transmission layer can be prepared by one of conventional atomic layer deposition, magnetron sputtering, chemical vapor deposition, pulsed laser deposition and thermal evaporation;

[0026] S10, forming a second anti-reflection layer on the lower end surface of the second transmission layer; the second anti-reflection layer can be prepared by using one of conventional plasma enhanced chemical vapor deposition, magnetron sputtering, electron beam evaporation deposition, jet thermal decomposition and sol-gel methods;

[0027] S11. Forming a second metal electrode on the lower end surface of the second anti-reflection layer so as to contact the lower end surface of the second anti-reflection layer. The second metal electrode may be a silver electrode. Specifically, screen-printing a metal grid line on the lower end surface of the second anti-reflection layer, and preparing the second metal electrode by high-temperature sintering in a forming gas atmosphere composed of nitrogen and hydrogen in a volume ratio of 95%:5%, wherein the high-temperature sintering temperature is 500-800°C and the sintering time is 10-40min.

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] In the present invention, a passivation contact structure is formed by depositing silicon oxide as the first passivation layer and doped zinc oxide as the first transmission layer on the front of the battery, which effectively reduces the composite loss caused by the direct contact between the electrode and silicon on the front of the TOPCon battery. The silicon oxide passivation layer is extremely thin, and the tunneling effect can be used to realize carrier transmission. At the same time, the density of interface dangling bonds is reduced, and excellent chemical passivation of the silicon surface is achieved. Doped zinc oxide is taken from wide-bandgap metal oxides such as aluminum-doped zinc oxide, boron-doped zinc oxide, and gallium-doped zinc oxide. Its optical band gap is wide (Eg>3.2eV), and it shows a relatively high optical transparency (T>90%) in a wide spectral band, and the optical parasitic absorption is relatively small. Considering the precise control of the structural parameters of doped zinc oxide and the requirements for impurity concentration, a low-temperature atomic layer deposition method is used to prepare the film; based on the self-limiting reaction, the proportion and thickness of zinc oxide doping elements are accurately regulated, which greatly improves its carrier concentration and mobility, and achieves good electrical properties.

[0030] In the present invention, the front first transmission layer is covered with a hydrogen-containing material aluminum oxide as a sacrificial layer, and the internal hydrogen diffuses to the interface during the thermal annealing process to fill the tunnel passivation layer defects and enhance passivation. Furthermore, the coverage of the sacrificial layer can effectively prevent hydrogen from overflowing from the contact and causing passivation to weaken.

[0031] In the present invention, a second passivation layer and a second transport layer are deposited on the back of the battery to form a passivation contact structure, thereby achieving excellent surface passivation and selective carrier transport. The low work function phosphorus-doped hydrogenated amorphous silicon material is deposited on the surface of n-type silicon to induce the energy band to bend downward, and the carrier transport capacity is made asymmetric through the band step effect of the conduction band and the valence band, so as to achieve selective electron transport and enhance field effect passivation.

[0032] In the present invention, by forming a passivation contact structure on both sides of the battery, the battery efficiency is further improved. The passivation contact structure is applied between the front emitter and the metal electrode of the battery, which greatly reduces the compound loss caused by direct contact and is conducive to forming a good ohmic contact and current collection. The use of amorphous silicon instead of polycrystalline silicon in the back passivation contact structure avoids the cost problem caused by the high-temperature crystallization process and the thermal damage to other parts of the battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 A schematic diagram of the structure of a double-sided passivated contact crystalline silicon solar cell according to an embodiment of the present invention;

[0034] Figure 2 A schematic diagram of the structure of a passivated contact crystalline silicon solar cell according to a comparative example of the present invention;

[0035] Figure 3The invention discloses a preparation process of a double-sided passivated contact crystalline silicon solar cell according to an embodiment of the present invention.

[0036] Figure 1 Figure numerals: 10 - n-type single crystal silicon substrate, 11 - boron-doped emitter layer, 12 - first passivation layer, 13 - first transmission layer, 14 - sacrificial layer, 15 - first anti-reflection layer, 16 - first metal electrode, 21 - second passivation layer, 22 - second transmission layer, 23 - second anti-reflection layer, 24 - second metal electrode. DETAILED DESCRIPTION

[0037] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with embodiments. The specific embodiments described herein are only used to explain the present invention and are not used to limit the invention.

[0038] Example 1

[0039] like Figure 1 As shown, this embodiment exemplarily shows a double-sided passivated contact crystalline silicon solar cell, comprising an n-type single crystal silicon substrate 10, the upper end surface of the n-type single crystal silicon substrate 10 is provided with a boron-doped emitter layer 11, a first passivation layer 12, a first transmission layer 13, a sacrificial layer 14 and a first anti-reflection layer 15 in sequence from bottom to top, the upper end surface of the first anti-reflection layer 15 is provided with a first metal electrode 16 in the form of a grid line, the end of the first metal electrode 16 sequentially penetrates the first anti-reflection layer 15 and the sacrificial layer 14 and contacts the upper end surface of the first transmission layer 13; the lower end surface of the n-type single crystal silicon substrate 10 is provided with a second passivation layer 21, a second transmission layer 22 and a second anti-reflection layer 23 in sequence from top to bottom, and the lower end surface of the second anti-reflection layer 23 is provided with a second metal electrode 24 in the form of a grid line. Figure 3 As shown, the specific preparation process of the double-sided passivated contact crystalline silicon solar cell is as follows:

[0040] (1) An n-type single crystal silicon substrate 10 with a thickness of 130 μm and a resistivity of 1.3 Ω·cm is selected as a substrate, and the n-type single crystal silicon substrate 10 is pre-cleaned to remove a surface cutting damage layer and subjected to an alkali texturing treatment;

[0041] (2) Using BBr3 as the boron source, the silicon wafer is diffused by high-temperature diffusion in a tubular diffusion furnace at a diffusion temperature of 1000°C for 20 min to form a boron-doped emitter layer 11. The diffusion square resistance of the boron-doped emitter layer 11 is 140Ω / Sq, and the surface concentration is 1×10 20 atoms / cm 3 , the doping junction depth is 0.4μm;

[0042] (3) using a chain HF solution with a concentration of 25% to remove the borosilicate glass on the back surface of the n-type single crystal silicon substrate 10;

[0043] (4) placing the n-type single crystal silicon substrate 10 with the boron-doped emitter layer 11 in a UV / ozone reaction chamber, heating it to 50° C. and reacting it for 5 minutes, and preparing a 1.5 nm silicon oxide as a first passivation layer 12 on the upper end surface of the boron-doped emitter layer 11;

[0044] (5) Boron-doped zinc oxide is deposited as the first transport layer 13 on the first passivation layer 12 by atomic layer deposition using diethyl zinc as the zinc source, water as the oxygen source, and isopropyl borate as the boron source. The specific process of depositing the boron-doped zinc oxide layer by atomic layer deposition is as follows: (1) The pulse precursor diethyl zinc source enters the reaction chamber for 80 ms, and a chemical adsorption reaction occurs on the exposed substrate surface; (2) The remaining precursor is purged with nitrogen for 10 s; (3) The pulse precursor oxygen source (ultrapure water) enters the reaction chamber for 80 ms and chemically adsorbs on the surface; (4) The remaining precursor is purged with nitrogen for 10 s. After repeating the above four steps 10 times, a pulse precursor isopropyl borate boron source is inserted into the reaction chamber for 80 ms and the remaining precursor is purged with nitrogen for 10 s. After repeating all the above steps 4 times, a boron-doped zinc oxide layer with a thickness of about 8 nm is obtained as the first transport layer 13;

[0045] (6) Aluminum oxide is deposited as a sacrificial layer 14 on the first transport layer 13 by atomic layer deposition using trimethylaluminum as an aluminum source and water as an oxygen source. The specific process of depositing the aluminum oxide sacrificial layer by atomic layer deposition is as follows: (1) The pulse precursor trimethylaluminum source enters the reaction chamber for 60ms, and a chemical adsorption reaction occurs on the exposed substrate surface; (2) The remaining precursor is purged with nitrogen for 10s; (3) The pulse precursor oxygen source (ultrapure water) enters the reaction chamber for 80ms, and chemical adsorption occurs on the surface; (4) The remaining precursor is purged with nitrogen for 10s. After repeating the above four steps 250 times, aluminum oxide with a thickness of about 27nm is obtained as the sacrificial layer 14. Take out the sample and put it into an annealing furnace, and heat it to 500°C for annealing for 30 minutes in a forming gas atmosphere composed of nitrogen and hydrogen in a volume ratio of 95%:5%;

[0046] (7) depositing 80 nm of silicon nitride as a first anti-reflection layer 15 on the sacrificial layer 14 at 500° C. by plasma enhanced chemical vapor deposition;

[0047] (8) removing a portion of the first anti-reflection layer 15 and the sacrificial layer 14 above the first transmission layer 13 by laser patterning;

[0048] (9) forming a first metal electrode 16 by screen printing an aluminum grid line on the upper end surface of the first transmission layer 13 at the laser-removed portion, heating to 500° C. and annealing for 30 minutes in a forming gas atmosphere composed of nitrogen and hydrogen in a volume ratio of 95%:5%;

[0049] (10) depositing 10 nm of intrinsic hydrogenated amorphous silicon as a second passivation layer 21, 10 nm of phosphorus-doped hydrogenated amorphous silicon as a second transmission layer 22, and 80 nm of tin-doped indium oxide as a second anti-reflection layer 23 on the lower end surface of the n-type single crystal silicon substrate 10 in sequence by plasma enhanced chemical vapor deposition;

[0050] (11) Silver paste is screen-printed on the side of the second anti-reflection layer away from the n-type silicon wafer to prepare a second metal electrode 24, thereby completing the preparation of a double-sided passivated contact crystalline silicon solar cell.

[0051] Comparative Example 1

[0052] like Figure 2 As shown, the comparative example is a passivated contact crystalline silicon solar cell, comprising an n-type single crystal silicon substrate 10, wherein a boron-doped emitter layer 11 and a first anti-reflection layer 12 are sequentially arranged on the upper end surface of the n-type single crystal silicon substrate 10 from bottom to top, a first metal electrode 13 is arranged on the upper end of the first anti-reflection layer 12, and the end of the first metal electrode 13 penetrates through the first anti-reflection layer 12 and contacts with the upper end surface of the boron-doped emitter layer 11; a tunneling passivation layer (i.e., the second passivation layer 21 in Example 1), an electron transport layer (i.e., the second transport layer 22 in Example 1) and a second anti-reflection layer 23 are sequentially arranged on the lower end surface of the n-type single crystal silicon substrate 10 from top to bottom, and a second metal electrode 24 is arranged on the lower end surface of the second anti-reflection layer 23.

[0053] The other preparation steps of Comparative Example 1 are the same as those of Example 1, except for steps S3, S4 and S5 for preparing the first passivation layer, the first transmission layer and the sacrificial layer on the upper end surface of the n-type single crystal silicon substrate.

[0054] The crystalline silicon solar cells prepared in Example 1 and Comparative Example 1 were subjected to a standard IV curve test, and the test results are shown in Table 1.

[0055] Table 1 Test results of battery efficiency prepared in comparative examples and examples

[0056] <![CDATA[J SC (mA / cm 2 )]]> <![CDATA[V OC (mV)]]> FF(%) PCE(%) Comparative Example 40.9 705.6 80.6 23.26 Example 41.84 721.6 83.96 25.21

[0057] As shown in Table 1, compared with the TOPcon cell of the comparative example, the short-circuit current density (J SC ), open circuit voltage (V OC ), fill factor (FF) and photoelectric conversion efficiency (PCE) have all been improved.

[0058] In summary, the present invention realizes a passivation contact structure on both the front and back sides of the battery, which improves the surface passivation effect of the battery while improving the optical parasitic absorption problem of the battery, effectively improving the open circuit voltage and short circuit current of the battery, thereby facilitating the improvement of the photoelectric conversion efficiency of the battery.

[0059] The technical solution of the present invention is not limited to the above-mentioned specific embodiments. All technical variations made according to the technical solution of the present invention fall within the protection scope of the present invention.

Claims

1. A double-sided passivated contact crystalline silicon solar cell, characterized in that: The invention comprises an n-type single crystal silicon substrate (10), wherein the upper end surface of the n-type single crystal silicon substrate (10) is provided with a boron-doped emitter layer (11), a first passivation layer (12), a first transmission layer (13), a sacrificial layer (14) and a first anti-reflection layer (15) in sequence from bottom to top, and the upper end surface of the first anti-reflection layer (15) is provided with a first metal electrode (16) in the form of a grid line, and the end of the first metal electrode (16) passes through the first anti-reflection layer (15) and the sacrificial layer (14) in sequence and contacts the upper end surface of the first transmission layer (13); and the lower end surface of the n-type single crystal silicon substrate (10) is provided with a second passivation layer (21), a second transmission layer (22) and a second anti-reflection layer (23) in sequence from top to bottom, and the lower end surface of the second anti-reflection layer (23) is provided with a second metal electrode (24) in the form of a grid line.

2. The double-sided passivated contact crystalline silicon solar cell according to claim 1, characterized in that: The material of the boron-doped emitter layer (11) is boron-doped single crystal silicon, the diffusion square resistance of the boron-doped emitter layer (11) is 100-300Ω / Sq, and the surface concentration is 8×10 19 -1×10 20 atoms / cm 3 The doping junction depth is 0.1~0.8μm.

3. The double-sided passivated contact crystalline silicon solar cell according to claim 1, characterized in that: The material of the first passivation layer (12) is silicon oxide, and the thickness of the first passivation layer (12) is 0.5-2.5 nm.

4. The double-sided passivated contact crystalline silicon solar cell according to claim 1, characterized in that: The material of the first transmission layer (13) is one or more of aluminum-doped zinc oxide, boron-doped zinc oxide and gallium-doped zinc oxide, and the thickness of the first transmission layer (13) is 3-80 nm.

5. The double-sided passivated contact crystalline silicon solar cell according to claim 1, characterized in that: The material of the sacrificial layer (14) is aluminum oxide or silicon nitride, and the thickness of the sacrificial layer (14) is 10-50 nm.

6. The double-sided passivated contact crystalline silicon solar cell according to claim 1, characterized in that: The material of the first anti-reflection layer (15) is one or more of aluminum oxide, silicon nitride, hydrogenated silicon nitride and magnesium fluoride, and the thickness of the first anti-reflection layer (15) is 20-200 nm.

7. The double-sided passivated contact crystalline silicon solar cell according to claim 1, characterized in that: The material of the second passivation layer (21) is silicon oxide or intrinsic hydrogenated amorphous silicon, and the thickness of the second passivation layer (21) is 1-10 nm.

8. The double-sided passivated contact crystalline silicon solar cell according to claim 1, characterized in that: The material of the second transmission layer (22) is one or more of phosphorus-doped polysilicon, phosphorus-doped hydrogenated amorphous silicon and doped zinc oxide, and the thickness of the second transmission layer (22) is 3-80 nm.

9. The double-sided passivated contact crystalline silicon solar cell according to claim 1, characterized in that: The material of the second anti-reflection layer (23) is one or more of tin-doped indium oxide, fluorine-doped tin oxide, aluminum-doped zinc oxide and indium-doped zinc oxide, and the thickness of the second anti-reflection layer (23) is 20-200 nm.

10. A method for preparing a double-sided passivated contact crystalline silicon solar cell according to any one of claims 1 to 9, characterized in that: The following steps are involved: S1, pre-cleaning and alkali texturing treatment of an n-type single crystal silicon substrate (10); S2, performing boron diffusion on the upper end surface of the n-type single crystal silicon substrate (10), so that the upper end surface of the n-type single crystal silicon substrate (10) is formed into a boron-doped emitter layer (11); S3, forming a first passivation layer (12) on the upper end surface of the boron-doped emitter layer (11); S4, forming a first transmission layer (13) on the upper end surface of the first passivation layer (12); S5, forming a sacrificial layer (14) on the upper end surface of the first transmission layer (13); S6, forming a first anti-reflection layer (15) on the upper end surface of the sacrificial layer (14); S7, forming a first metal electrode (16) on the first anti-reflection layer (15) that penetrates the first anti-reflection layer (15) and the sacrificial layer (14) and contacts the upper end surface of the first transmission layer (13); S8, forming a second passivation layer (21) on the lower end surface of the n-type single crystal silicon substrate (10); S9, forming a second transmission layer (22) on the lower end surface of the second passivation layer (21); S10, forming a second anti-reflection layer (23) on the lower end surface of the second transmission layer (22); S11. Forming a second metal electrode (24) on the lower end surface of the second anti-reflection layer (23) so as to be in contact with the lower end surface of the second anti-reflection layer (23).

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