Perovskite solar cell and preparation method thereof

Abstract

The invention discloses a perovskite solar cell and a preparation method thereof. The perovskite solar cell comprises a substrate, a bottom electrode layer, a first carrier transport layer, a perovskite layer, a passivation layer, a second carrier transport layer and a top electrode layer which are stacked. The bottom electrode layer is provided with a first scribing groove penetrating through the bottom electrode layer; the first carrier transport layer and the perovskite layer are provided with a 1.5-th etching groove penetrating through the first carrier transport layer and the perovskite layer; a second scribing groove is formed in the area, located in the 1.5-th scribing groove, of the passivation and second carrier transmission layer; and a third scribing groove penetrating through the top electrode layer and the passivation and second carrier transmission layer is formed in the area, located in the 1.5-th scribing groove, of the top electrode layer. According to the invention, the 1.5-th scribed line groove is arranged, and the second scribed line groove and the third scribed line groove are arranged in the 1.5-th scribed line groove, so that the edge burrs of the second scribed line groove and the interface defects of the third scribed line groove in the prior art can be reduced, the crater height is reduced, and the electric leakage risk can be reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of solar cells, in particular to a perovskite solar cell and a preparation method thereof. BACKGROUND

[0002] In the preparation process of the perovskite solar cell, the laser etching technology is a key link for realizing the series connection of sub-cells, and three process parameters of the first etching groove (transparent conductive oxide layer etching), the second etching groove (first carrier transport layer (HTL) / perovskite layer / passivation layer / second carrier transport layer (ETL) etching) and the third etching groove (top electrode etching) directly affect the device performance. The prior art has the following problems: I. Edge burr of the second etching groove After the traditional process completes the deposition of the passivation layer and the second carrier transport layer (ETL), the second etching groove etching (through the ETL / passivation layer / perovskite layer / HTL structure) is performed, and when high-energy laser (typical energy density 1.5 J / cm 2 ) is used for processing, part of the laser energy will penetrate the ETL and the passivation layer and be absorbed by the perovskite layer, inducing mechanical stress impact due to thermal expansion of the material inside. Due to the intrinsic brittleness of the perovskite material, edge burrs with a crater-like morphology and local edge collapse phenomenon are easily formed in this process. This typical laser processing defect will lead to: (1) local short circuit channels are formed during subsequent electrode filling, which increases the leakage current by 30-50 μA / cm 2 ; (2) the interface contact resistance increases significantly.

[0003] II. Interface defects of the third etching groove etching In the top electrode etching process, thermodynamic effects cause the material to be removed mainly through two mechanisms: molten state flow and vapor jetting. This process easily forms crater-like protrusions with a height of about 2 μm at the interface, which is particularly pronounced in the metal-metal oxide composite electrode system. These microscopic defects will trigger a double failure mechanism: (1) they become the preferred diffusion path for moisture penetration during component packaging; (2) under the action of mechanical stress, the protruding structure can penetrate the encapsulation layer and contact the bottom electrode, causing permanent damage to the device.

[0004] The existing improvement scheme is mainly based on femtosecond laser or beam shaping technology, which can partially suppress the crater effect, but has significant limitations: (1) the defect control effect does not meet the theoretical expectation; (2) the equipment investment cost is high; (3) the process parameter window is narrow.

[0005] In view of this, the present application is proposed. SUMMARY

[0006] The perovskite solar cell and the preparation method have the advantages that the generation and increase of the "crater" defects at the scribing groove are inhibited, and the risk of electric leakage is reduced.

[0007] The present application is implemented in this way: In a first aspect, the present application provides a perovskite solar cell, comprising a substrate, a bottom electrode layer, a first carrier transport layer and a perovskite layer, a passivation and a second carrier transport layer and a top electrode layer which are sequentially stacked on the substrate; The bottom electrode layer is provided with a first scribing groove penetrating the bottom electrode layer; The first carrier transport layer and the perovskite layer cover the bottom electrode layer and fill the first scribing groove; the first carrier transport layer and the perovskite layer are provided with a first 1.5 scribing groove, and the first 1.5 scribing groove penetrates the first carrier transport layer and the perovskite layer; The passivation and the second carrier transport layer cover the first carrier transport layer and the perovskite layer and cover the groove bottom and the sidewall of the first 1.5 scribing groove, and the passivation and the second carrier transport layer are provided with a second scribing groove in the area of the first 1.5 scribing groove, and the second scribing groove penetrates the passivation and the second carrier transport layer; The top electrode layer covers the passivation and the second carrier transport layer and fills the first 1.5 scribing groove and the second scribing groove, and the top electrode layer is further provided with a third scribing groove penetrating the top electrode layer and the passivation and the second carrier transport layer; the third scribing groove is located in the area of the first 1.5 scribing groove, and the third scribing groove is located on the side of the second scribing groove away from the first scribing groove.

[0008] In an optional embodiment, the first 1.5 scribing groove has a line width of 100-300 μm; And / or, the first scribing groove has a width of 15-50 μm, and the distance between the first scribing groove and the first 1.5 scribing groove is 50-150 μm; And / or, the second scribing groove has a line width of 30-200 μm, and the distance between the edge of the second scribing groove and the edge of the first 1.5 scribing groove close to the second scribing groove is 10-50 μm; And / or, the third scribing groove has a line width of 20-50 μm, and the distance between the third scribing groove and the first 1.5 scribing groove close to the third scribing groove is 10-50 μm.

[0009] In an optional embodiment, the material of the bottom electrode layer is selected from at least one of ITO, FTO, IZO and AZO; And / or, the first carrier transport layer and the perovskite layer comprise a first carrier transport layer and a perovskite layer which are sequentially stacked on the bottom electrode layer; And / or, the passivation and second carrier transport layer comprises a passivation layer and a second carrier transport layer which are sequentially stacked on the perovskite layer. And / or, the material of the top electrode layer is selected from at least one of silver, copper, gold, aluminum, ITO and FTO.

[0010] In an optional embodiment, the first carrier transport layer is a hole transport layer. And / or, the material of the first carrier transport layer is selected from at least one of Spiro-MeOTAD, nickel oxide, tin oxide, titanium dioxide, zinc oxide, vanadium oxide, molybdenum oxide, tungsten oxide and C60 and its derivatives. And / or, the material of the perovskite layer is an ABX3 type perovskite material, wherein A is selected from at least one of Cs, K, Rb, MA and FA, B is selected from at least one of Pb, Sn and Zr, and X is selected from at least one of Br, I and Cl.

[0011] In an optional embodiment, the second carrier transport layer is an electron transport layer. And / or, the material of the second carrier transport layer is selected from at least one of nickel oxide, tin oxide, titanium dioxide, zinc oxide, ZnTiO3, tungsten oxide and C60 and its derivatives. And / or, the material of the passivation layer is selected from at least one of 1,2-propanediamine hydroiodide, phenethylammonium iodide, ammonium thiocyanate, LiF and Al2O3.

[0012] In a second aspect, the application provides a preparation method of the perovskite solar cell according to any one of the preceding embodiments, comprising: forming a bottom electrode layer on a substrate, and performing laser scribing on the bottom electrode layer to form a first scribe groove; forming a first carrier transport layer and a perovskite layer on the bottom electrode layer, and performing laser scribing on the first carrier transport layer and the perovskite layer to form a first and a half scribe groove; forming a passivation and second carrier transport layer on the first carrier transport layer and the perovskite layer, and performing laser scribing on the passivation and second carrier transport layer to form a second scribe groove; forming a top electrode layer on the passivation and second carrier transport layer, and performing laser scribing on the top electrode layer to form a third scribe groove.

[0013] In an optional embodiment, the laser pulse width used for laser scribing is 10-14 ps. And / or, the laser used for laser scribing is Gaussian light.

[0014] In an optional embodiment, the preparation method of the first carrier transport layer and the perovskite layer in the perovskite layer is selected from at least one of doctor blade coating, slot coating, spray coating, inkjet printing, vacuum evaporation, and spin coating. In an optional embodiment, the preparation method of the bottom electrode, the first carrier transport layer in the first carrier transport layer and the perovskite layer, the second carrier transport layer in the passivation layer and the second carrier transport layer, the passivation layer in the passivation layer and the second carrier transport layer, and the top electrode is independently selected from at least one of doctor blade coating, slot coating, magnetron sputtering, vacuum evaporation, and electron beam evaporation.

[0015] In an optional embodiment, the ultraviolet wavelength of the laser used for laser scribing is 340-370 nm, or the green wavelength of the laser used for laser scribing is 510-540 nm. In an optional embodiment, the single pulse energy of the laser used for laser scribing is 10-25 muJ. In an optional embodiment, the laser used for laser scribing is selected from a solid laser.

[0016] In an optional embodiment, the laser used for forming the first scribe groove is incident on the bottom electrode layer, and the focal point of the laser is 0-0.2 mm away from the surface of the bottom electrode layer; or the laser used for forming the first scribe groove is incident on the substrate surface, and the focal point of the laser is 0-0.2 mm away from the upper surface of the substrate. In an optional embodiment, the laser used for forming the first scribe groove, the second scribe groove, and the third scribe groove is incident on the film surface.

[0017] The present application has the following advantages: The perovskite solar cell in the present application has the first 1.5 scribe groove, and the second scribe groove and the third scribe groove are arranged in the first 1.5 scribe groove, which is beneficial to reduce the edge burr of the second scribe groove and the interface defect of the third scribe groove, reduce the height of the crater, and reduce the risk of electric leakage. BRIEF DESCRIPTION OF DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments. It should be understood that the following drawings only show some embodiments of the present application, and therefore should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can also be obtained without creative labor on the basis of these drawings.

[0019] Figure 1 The figure is a schematic diagram of the component structure prepared for the perovskite solar cell in Example 1.

[0020] Figure 2 The figure is a schematic diagram of the component structure prepared for the perovskite solar cell in Comparative Example 1. The figure is a schematic diagram of the component structure prepared for the perovskite solar cell in Comparative Example 1.

[0021] Figure 3 FIG. 2 shows a schematic diagram of the second and third scribe grooves and the crater case for the preparation of the component of the perovskite solar cell in Example 1.

[0022] Figure 4 FIG. 2 shows a schematic diagram of the second and third scribe grooves and the crater case for the preparation of the component of the perovskite solar cell in Example 1.

[0023] FIG. 1 shows a schematic diagram of the perovskite solar cell according to the present application, in which: 1, substrate; 2, bottom electrode layer; 3, first carrier transport layer and perovskite layer; 4, passivation and second carrier transport layer; 5, top electrode layer. P1, first scribe groove; P1.5, first and a half scribe groove; P2, second scribe groove; P3, third scribe groove. DETAILED DESCRIPTION

[0024] In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below. If specific conditions are not specified in the embodiments, the conventional conditions or the conditions recommended by the manufacturers are used. If the reagents or instruments used are not specified by the manufacturers, they are all conventional products that can be purchased in the market.

[0025] The embodiments of the present application provide a perovskite solar cell, as shown in FIG. 1, which comprises a substrate 1 and a bottom electrode layer 2, a first carrier transport layer and perovskite layer 3, a passivation and second carrier transport layer 4 and a top electrode layer 5 which are sequentially stacked on the substrate 1. Figure 1 A first scribe groove P1 is provided on the bottom electrode layer 2 and penetrates the bottom electrode layer 2. The first carrier transport layer and perovskite layer 3 covers the bottom electrode layer 2 and fills the first scribe groove P1. A first and a half scribe groove P1.5 is provided on the first carrier transport layer and perovskite layer 3 and penetrates the first carrier transport layer and perovskite layer 3. The passivation and second carrier transport layer 4 covers the first carrier transport layer and perovskite layer 3 and covers the groove bottom and sidewall of the first and a half scribe groove P1.5, and the passivation and second carrier transport layer 4 is provided with a second scribe groove P2 in the area of the first and a half scribe groove P1.5, and the second scribe groove P2 penetrates the passivation and second carrier transport layer 4. The passivation and second carrier transport layer 4 covers the first carrier transport layer and perovskite layer 3 and covers the groove bottom and sidewall of the first and a half scribe groove P1.5, and the passivation and second carrier transport layer 4 is provided with a second scribe groove P2 in the area of the first and a half scribe groove P1.5, and the second scribe groove P2 penetrates the passivation and second carrier transport layer 4. The top electrode layer 5 covers the passivation and second carrier transport layer 4 and fills the first 1.5 scribe groove P1.5 and the second 2 scribe groove P2, and a third 3 scribe groove P3 is further provided on the top electrode layer 5 and the passivation and second carrier transport layer 4, wherein the third 3 scribe groove P3 is located in the region of the first 1.5 scribe groove P1.5, and the third 3 scribe groove P3 is located on the side of the second 2 scribe groove P2 away from the first 1 scribe groove P1.

[0026] The perovskite solar cell in the present application is provided with the first 1.5 scribe groove P1.5, and the second 2 scribe groove P2 and the third 3 scribe groove P3 are arranged in the first 1.5 scribe groove P1.5, which is beneficial to reduce the edge burr of the second 2 scribe groove P2 and the interface defect of the third 3 scribe groove P3, reduce the height of the crater, and reduce the risk of electric leakage.

[0027] In an optional embodiment, the line width of the first 1.5 scribe groove P1.5 is 100-300 μm, for example, 100 μm, 122 μm, 144 μm, 166 μm, 188 μm, 210 μm, 232 μm, 254 μm, 276 μm, 298 μm, or 300 μm.

[0028] In an optional embodiment, the width of the first 1 scribe groove P1 is 15-50 μm, for example, 15 μm, 19 μm, 23 μm, 27 μm, 31 μm, 35 μm, 39 μm, 43 μm, 47 μm, or 50 μm; and the spacing between the first 1 scribe groove P1 and the first 1.5 scribe groove P1.5 is 50-150 μm, for example, 50 μm, 61 μm, 72 μm, 83 μm, 94 μm, 105 μm, 116 μm, 127 μm, 138 μm, 149 μm, or 150 μm.

[0029] In an optional embodiment, the line width of the second 2 scribe groove P2 is 30-200 μm, for example, 30 μm, 49 μm, 68 μm, 87 μm, 106 μm, 125 μm, 144 μm, 163 μm, 182 μm, or 200 μm; and the distance between the edge of the second 2 scribe groove P2 and the edge of the first 1.5 scribe groove P1.5 close to the second 2 scribe groove P2 is 10-50 μm, for example, 10 μm, 14 μm, 18 μm, 22 μm, 26 μm, 30 μm, 34 μm, 38 μm, 42 μm, 46 μm, or 50 μm.

[0030] In an optional embodiment, the line width of the third scribe groove P3 is 20-50 μm, for example 20 μm, 23 μm, 26 μm, 29 μm, 32 μm, 35 μm, 38 μm, 41 μm, 44 μm, 47 μm, or 50 μm; the distance between the third scribe groove P3 and the edge of the first 1.5 scribe groove P1.5 close to the third scribe groove P3 is 10-50 μm, for example 10 μm, 14 μm, 18 μm, 22 μm, 26 μm, 30 μm, 34 μm, 38 μm, 42 μm, 46 μm, or 50 μm.

[0031] By optimizing the positions and widths of the first 1.5 scribe groove P1.5 and the first 1 scribe groove P1, the second 2 scribe groove P2, and the third 3 scribe groove P3, the short-circuit current density (JSC), the open-circuit voltage (VOC), the fill factor (FF), and the photoelectric conversion efficiency (PCE) of the perovskite solar cell can be further improved while reducing the height of the crater.

[0032] In an optional embodiment, the material of the bottom electrode layer 2 is selected from at least one of ITO, FTO, IZO, and AZO, has high conductivity and light transmittance, and can efficiently collect carriers and allow light to pass through.

[0033] In an optional embodiment, the first carrier transport layer and the perovskite layer 3 include a first carrier transport layer and a perovskite layer that are sequentially stacked on the bottom electrode layer 2, and the carrier extraction and transport path can be optimized.

[0034] In an optional embodiment, the passivation and second carrier transport layer 4 includes a passivation layer and a second carrier transport layer that are sequentially stacked on the perovskite layer. The combination of the passivation layer and the second carrier transport layer can reduce interface recombination and protect the perovskite layer, thereby improving the stability and efficiency of the battery.

[0035] In an optional embodiment, the material of the top electrode layer 5 is selected from at least one of silver, copper, gold, aluminum, ITO, and FTO, and both conductivity and cost are considered.

[0036] In an optional embodiment, the first carrier transport layer is a hole transport layer.

[0037] In an optional embodiment, the material of the first carrier transport layer is selected from at least one of Spiro-MeOTAD (2,2',7,7'-tetrakis [N,N'-di (4-methoxyphenyl) amino]-9,9'-spirobifluorene], nickel oxide, tin oxide, titanium dioxide, zinc oxide, vanadium oxide, molybdenum oxide, tungsten oxide, and C60 and its derivatives, which can provide a matching energy level for hole or electron transport and improve extraction efficiency.

[0038] In an optional embodiment, the perovskite layer is made of ABX3 type perovskite material, wherein A is selected from Cs, K, Rb, MA (CH3NH3). + ) and FA (HC(NH2)2 + At least one of the following, B is selected from at least one of Pb, Sn and Zr, and X is selected from at least one of Br, I and Cl. The light absorption and stability are optimized by regulating the A, B and X site elements.

[0039] In an optional embodiment, the second carrier transport layer is an electron transport layer.

[0040] In an optional embodiment, the material of the second carrier transport layer is selected from at least one of nickel oxide, tin oxide, titanium dioxide, zinc oxide, ZnTiO3, tungsten oxide, and C60 and its derivatives, which is beneficial to ensure efficient carrier transport.

[0041] In an optional embodiment, the material of the passivation layer is selected from at least one of 1,2-propanediamine hydroiodic acid (PDADI), phenylethyl ammonium iodide (PEAI), ammonium thiocyanate, LiF, and Al2O3, which helps to reduce interfacial recombination and protect the perovskite, thereby improving the overall battery efficiency and lifespan.

[0042] This application also provides a method for preparing a perovskite solar cell according to any one of the foregoing embodiments, comprising: A bottom electrode layer 2 is formed on a substrate, and a first scribe line groove P1 is formed on the bottom electrode layer 2 by laser scribing. A first carrier transport layer and a perovskite layer 3 are formed on the bottom electrode layer 2, and a first 1.5 groove P1.5 is formed by laser scribing on the first carrier transport layer and the perovskite layer 3. A passivation layer and a second carrier transport layer 4 are formed on the first carrier transport layer and the perovskite layer 3, and a second groove P2 is formed by laser scribing on the passivation layer and the second carrier transport layer 4.

[0043] A top electrode layer 5 is formed on the passivation and second carrier transport layer 4, and a third groove P3 is formed on the top electrode layer 5 by laser scribing.

[0044] This application can effectively optimize the etching effect of perovskite solar cells by adjusting the etching sequence, thereby improving the stability of perovskite solar cells and reducing the risk of leakage current. Specifically: 1. Laser etching is performed only on the perovskite layer and the first carrier transport layer to obtain the 1.5 groove P1.5. The resulting groove has smooth edges without "crater" defects. The passivation layer and the second carrier transport layer that are subsequently prepared can adhere tightly to the bottom electrode layer 2, laying the foundation for the subsequent etching of the second groove P2 and avoiding the generation of "crater" defects in the etching step of the second groove P2.

[0045] 2. After etching groove P1.5, the passivation layer and the second carrier transport layer can cover both sides of the groove to form an effective isolation structure, preventing the metal electrode from directly contacting the perovskite layer, thereby suppressing the chemical reaction between the two and significantly enhancing the stability of the battery module.

[0046] 3. When etching the top electrode, passivation layer and second carrier transport layer in the P1.5 groove, the material adhesion is stronger and the laser power threshold difference with the bottom electrode layer 2 is significant. This can achieve interface separation while basically eliminating the "crater" defect and greatly reducing the risk of leakage after component packaging.

[0047] In summary, this application improves the performance and reliability of perovskite solar cell modules by optimizing the etching effect and interlayer structure of each step, P1.5, P2, and P3, thereby reducing defects, isolating reactions, and reducing leakage current.

[0048] In an optional embodiment, the laser pulse width used for laser marking is 10-14 ps, such as 10.0 ps, ​​10.4 ps, 10.8 ps, 11.2 ps, 11.6 ps, 12.0 ps, ​​12.4 ps, 12.8 ps, 13.2 ps, 13.6 ps, or 14.0 ps. This application can use a picosecond laser to achieve or even surpass the effect of using a femtosecond laser in the prior art, which is beneficial for cost savings.

[0049] In an optional embodiment, the laser used for laser marking is Gaussian light. This application can use Gaussian light to achieve or even surpass the effect of using flat-top light in the prior art, which is beneficial to saving costs.

[0050] In an optional embodiment, the preparation method of the first carrier transport layer and the perovskite layer 3 is selected from at least one of blade coating, slot coating, spraying, inkjet printing, vacuum evaporation, and spin coating.

[0051] In an optional embodiment, the preparation methods of the bottom electrode, the first carrier transport layer and the first carrier transport layer in the perovskite layer 3, the passivation and the second carrier transport layer 4, the passivation and the passivation layer in the second carrier transport layer 4, and the top electrode are each independently selected from at least one of blade coating, slot coating, magnetron sputtering, vacuum evaporation, and electron beam evaporation.

[0052] The above methods cover solution methods and physical vapor phase methods, taking into account both large-area preparation (such as blade coating) and high-precision film formation (such as vapor deposition), which can adapt to different layer requirements and facilitate a balance between efficiency and mass production.

[0053] In optional embodiments, the ultraviolet wavelength of the laser used for laser scribing is 340–370 nm, such as 340 nm, 343 nm, 346 nm, 349 nm, 352 nm, 355 nm, 358 nm, 361 nm, 364 nm, 367 nm, or 370 nm; or the green wavelength of the laser used for laser scribing is 510–540 nm, such as 510 nm, 513 nm, 516 nm, 519 nm, 522 nm, 525 nm, 528 nm, 531 nm, 534 nm, 537 nm, or 540 nm. Ultraviolet light etching of metal materials is beneficial for suppressing cratering, but it can lead to perovskite decomposition, resulting in an excessively large dead zone. Therefore, the wavelength of the laser used in this laser can be selected according to the material of each layer.

[0054] In an optional embodiment, the laser single pulse energy used for laser marking is 10 to 25 μJ, for example 10 μJ, 12 μJ, 14 μJ, 16 μJ, 18 μJ, 20 μJ, 22 μJ, 24 μJ, or 25 μJ.

[0055] In an optional embodiment, the laser used for laser marking is selected from solid-state lasers.

[0056] A solid-state laser with a single-pulse energy of 10–25 μJ provides moderate energy for precise etching of the target layer, reducing damage to surrounding materials and avoiding over-etching or under-etching.

[0057] In an optional embodiment, the laser incident direction used to form the first etched groove P1 is incident on the bottom electrode layer 2, and the laser focal point is 0-0.2 mm away from the surface of the bottom electrode layer 2, for example, 0 mm, 0.02 mm, 0.04 mm, 0.06 mm, 0.08 mm, 0.10 mm, 0.12 mm, 0.14 mm, 0.16 mm, 0.18 mm, or 0.20 mm; or the laser incident direction used to form the first etched groove P1 is incident on the substrate surface, and the laser focal point is 0-0.2 mm away from the upper surface of the substrate, for example, 0 mm, 0.02 mm, 0.04 mm, 0.06 mm, 0.08 mm, 0.10 mm, 0.12 mm, 0.14 mm, 0.16 mm, 0.18 mm, or 0.20 mm.

[0058] In an optional embodiment, the laser incident direction used to form the 1.5 groove P1.5, the 2nd groove P2, and the 3rd groove P3 is incident on the film surface.

[0059] The first etch groove is incident from the bottom electrode or substrate surface, with the focal point close to the surface, allowing for precise control of the etching depth. The fifth etch groove (P1.5), the second etch groove (P2), and the third etch groove (P3) are incident from the film surface, adapting to the stacked structure and ensuring complete etching of the target layer. Properly selecting the incident direction helps improve etch accuracy, reduce edge defects (such as crater-like defects), enhance interlayer isolation, reduce leakage risk, and improve component stability and yield.

[0060] The features and performance of the present invention will be further described in detail below with reference to embodiments.

[0061] Example 1 This embodiment provides a method for fabricating a perovskite solar cell, specifically including the following steps: Step 1: Take a 3.2mm thick ITO glass and remove surface dust particles or other foreign matter by water washing, plasma cleaning, and ultrasonic cleaning to serve as the bottom electrode; Step 2: Perform MARK cross laser marking on the obtained bottom electrode substrate. Use a 355nm laser for etching. The laser parameters are as follows: power 5W, repetition frequency 400kHz, pulse width 11ps, and processing speed 300mm / s.

[0062] Step 3: On the bottom electrode substrate with MARK, the MK is grasped and positioned, and then the first groove P1 is laser etched. The laser parameters are as follows: green light 532nm laser with precise focus etching, power 1.5W, repetition frequency 100kHz, pulse width 13ps, and scribing speed 500mm / s, forming the first groove P1 with a width of 20μm. The first groove P1 etches the ITO conductive layer without damaging the glass. The insulation resistance of the groove is >20MΩ. Then, it is washed with water again to remove the ITO debris and particles generated during the etching process. Step 4: On the substrate with the first etched groove P1, a 20 nm thick nickel oxide layer is prepared by magnetron sputtering as the first carrier transport layer; a perovskite precursor solution is prepared using Cs. 0.1 FA 0.9 The precursor combination of PbI3 was weighed and dissolved in DMF (N,N-dimethylformamide) after thorough stirring to obtain a precursor solution. The precursor solution was coated onto the nickel oxide layer using a slit coating process. The substrate was then transferred to a hot plate at 140°C and crystallized and annealed for 30 min to obtain a 550 nm thick perovskite film. Step 5: Laser etching of groove 1.5 P1.5 is performed on the right side of groove 1 P1 obtained in step 4. The right edge of groove 1 P1 is 50 μm away from the left edge of groove 1.5 P1.5. Green 532nm laser is used for positive defocusing etching at 1.4 mm. The laser parameters are as follows: power 0.5W, repetition frequency 400kHz, pulse width 13ps, and scribing speed 500mm / s, forming groove 1.5 P1.5 with a width of 200 μm. Groove 1.5 P1.5 pierces through the perovskite layer and the first carrier transport layer, but does not damage the ITO bottom electrode. Step 6: On the substrate obtained in step 5, a 5nm PDADI layer is prepared as a passivation layer by vacuum heating evaporation process; then a 20nm C60 layer and a 15nm tin oxide layer are prepared as the second carrier transport layer. Step 7: The substrate obtained in Step 6 is picked up and marked for laser etching of the second groove P2. A 532nm green laser is used for precise focusing and etching with a laser power of 0.5W, a laser frequency of 100kHz, a laser pulse width of 13ps, and a laser processing speed of 500mm / s to form the second groove P2 with a width of 50μm. The left edge of the second groove P2 is 30μm away from the left edge of the first and fifth grooves P1.5. The second groove P2 etched through the second carrier transport layer and the passivation layer, exposing the bottom TCO (Transparent Conductive Oxide), i.e., the bottom electrode layer. Step 8: Top electrode film is deposited on the substrate obtained in step 7. 100 nm Ag is deposited on the surface as the top electrode by magnetron sputtering. The top electrode can form a series circuit with ITO through the second scribe line groove P2. Step 9: The substrate obtained in Step 8 is picked up and laser-etched to form the third groove P3 using a 355nm ultraviolet laser. Laser parameters are: power 0.75W, repetition rate 70kHz, pulse width 11ps, quasi-focus etching, and laser processing speed 500mm / s, forming a 30μm wide third groove P3. The right edge of the third groove P3 is 30μm away from the right edge of the 1.5 groove P1.5. The third groove P3 etched through the Ag electrode, passivation layer, and second carrier transport layer without damaging the bottom electrode, resulting in the structure shown below. Figure 1 The perovskite solar cell shown.

[0063] Example 2: This embodiment provides a method for preparing a perovskite solar cell. The only difference from Embodiment 1 is that the center line of the second groove P2 coincides with the left edge of the first and fifth groove P1.5, and the center line of the third groove P3 coincides with the right edge of the first and fifth groove P1.5. All other conditions remain unchanged.

[0064] Comparative Example 1: This comparative example provides a method for fabricating a perovskite solar cell, specifically including the following steps: Step 1: Take a 3.2mm thick ITO glass and remove surface dust particles or other foreign matter by water washing, plasma cleaning, and ultrasonic cleaning to serve as the bottom electrode; Step 2: Mark cross laser marking is performed on the obtained bottom electrode substrate, and etching is performed by focusing a 355nm laser. The laser parameters are as follows: power 5W, repetition frequency 400kHz, pulse width 11ps, and processing speed 300mm / s.

[0065] Step 3: On the bottom electrode substrate with MARK, the MK is grasped and positioned before laser etching of the first groove P1. A 532nm green laser is used for focused etching with the following parameters: power 1.5W, repetition frequency 100kHz, pulse width 13ps, and etching speed 500mm / s, forming the first groove P1 with a width of 20μm. The first groove P1 etches the ITO conductive layer without damaging the glass. The insulation resistance of the groove is >20MΩ. Then, the ITO debris and particles generated during the etching process are removed by water washing. Step 4: On the substrate with the first etched groove P1, a 20 nm thick nickel oxide layer is prepared by magnetron sputtering as the first carrier transport layer; a perovskite precursor solution is prepared using Cs. 0.1 FA 0.9 The precursor combination of PbI3 was weighed and dissolved in DMF (N,N-dimethylformamide) after thorough stirring to obtain a precursor solution. The precursor solution was coated onto the first carrier transport layer using a slit coating process. The substrate was then transferred to a hot plate at 140°C and crystallized and annealed for 30 min to obtain a 550 nm thick perovskite film. A 5 nm PDADI layer was prepared on the perovskite film as a passivation layer using a vacuum heating evaporation process. Subsequently, a 20 nm C60 material and a 15 nm tin oxide were prepared as the second carrier transport layer. Step 5: Mark is picked up on the substrate obtained in step 4 and laser etching is performed on the second groove P2. Green light is used for 532nm positive defocus etching at a depth of 1.4mm. The laser parameters are as follows: power 0.7W, repetition frequency 400kHz, pulse width 13ps, and etching speed 500mm / s, forming a second groove P2 with a width of 50μm. The second groove P2 etched through the second carrier transport layer, the perovskite layer, and the first carrier transport layer, but without damaging the ITO bottom electrode. Step 6: A top electrode is deposited on the substrate surface obtained in step 4. A 100nm Ag layer is deposited on the surface as the top electrode by magnetron sputtering. The top electrode can form a series circuit with ITO through the second scribe line groove P2. Step 7: The substrate obtained in Step 5 is picked up and subjected to laser etching of the third groove P3 using a 355nm ultraviolet laser. Laser parameters are: power 0.7W, repetition rate 70kHz, pulse width 11ps, quasi-focus etching, and laser processing speed 500mm / s, forming a third groove P3 with a width of 30μm. The third groove P3 penetrates the Ag electrode, passivation layer, second carrier transport layer, and perovskite layer, causing the electrode to break at the etched line of the third groove P3, resulting in the structure shown below. Figure 2 The perovskite solar cell shown.

[0066] Comparative Example 2: This embodiment provides a method for fabricating a perovskite solar cell. The only difference from Comparative Example 1 is that in step 5, a green laser with a pulse width of 500 fs and a wavelength of 515 nm is used, with laser parameters of 0.5 W power, 500 kHz repetition rate, and 600 mm / s scribing speed; and in step 7, an ultraviolet laser with a pulse width of 300 fs and a wavelength of 343 nm is used, with laser parameters of 0.4 W power, 100 kHz repetition rate, and 500 mm / s scribing speed.

[0067] Comparative Example 3: This embodiment provides a method for fabricating a perovskite solar cell. The only difference from Comparative Example 1 is that the optical path in steps 5 and 7 is adjusted to a flat-top light, wherein the power of the laser parameter in step 7 is increased to 1.1W, while other conditions remain unchanged.

[0068] Comparative Example 4: This embodiment provides a method for fabricating a perovskite solar cell. The only difference from Embodiment 1 is that a passivation layer is not deposited in step 6, while other conditions remain unchanged.

[0069] Figure 3 and Figure 4 The images show the edge morphology of the second groove P2 and the third groove P3 of the perovskite solar cells prepared in Example 1 and Comparative Example 1, respectively. A comparison clearly shows that the edges of groove 1.5 P1.5 and groove 2 P2 in Example 1 are very smooth with almost no crater, and the crater height of groove 3 P3 is measured to decrease from 3 μm to less than 500 nm. The crater height of groove 3 P3 in Comparative Example 1 is shown in the image. Figure 4The height of the area within the red box in Example 1 is significantly higher than in Example 1. In Example 1, the laser etching process involves a localized area of ​​the electrode followed by laser penetration through the passivation layer and the second transport layer to the perovskite layer. The perovskite layer molecules absorb energy, undergoing energy level transitions and increasing temperature, forming plasma that increases pressure. The airflow impacts and "breaks open" the passivation layer and the second carrier transport layer 4, thus affecting the melting, solidification, and regeneration of the metal electrode. In Example 1, however, there is no perovskite layer under the third groove P3. The metal electrode is subjected to Gaussian light, and the third groove P3 gradually melts from the center to both sides. After the second carrier transport layer is exposed, it is subjected to laser light and heat conduction, resulting in instantaneous high temperature plasma vaporization, which does not significantly affect the melting and regeneration of the metal electrode. This application found that the higher the adhesion between the metal electrode and its underlying substrate 1, the lower the crater created by laser etching.

[0070] The performance of the perovskite solar cells prepared in the above embodiments and comparative examples was tested, and the test results are shown in Table 1.

[0071] Table 1

[0072] By comparing the performance tests of Example 1 and Comparative Example 1 in Table 1, it can be seen that the turn-on voltage and fill factor of the perovskite solar cell in Example 1 were improved to a certain extent, and the conversion efficiency was also significantly improved compared with Comparative Example 1. A comparison between Example 1 and Example 2 shows that when half of the second groove P2 and the third groove P3 fall outside the first and fifth groove P1.5, the edge morphology of the second groove P2 and the third groove P3 in the perovskite solar cell is similar to... Figure 3 In contrast, the second groove P2 and the third groove P3 are located on the outer edge of the first and fifth groove P1.5, which creates a crater-like effect on the interface contact between functional layers, resulting in a certain degree of loss in voltage and current.

[0073] Comparative Example 2 uses femtosecond laser etching for the second groove P2 and the third groove P3. The edge morphology of the second groove P2 and the third groove P3 of the fabricated perovskite solar cell is similar to... Figure 4 In comparison, the edge morphology of the groove is better, and the crater is improved compared to Comparative Example 1, but it is not as good as Example 1. Although the various data of photoelectric testing are better than Comparative Example 1, they are still slightly inferior to Example 1.

[0074] Comparative Example 3 uses beam shaping to convert Gaussian light into flat-top light, and the edge morphology of the third groove P3 of the fabricated perovskite solar cell is similar to... Figure 4 In comparison, the edge morphology of the third groove P3 is better, the crater is improved compared to Comparative Example 1, but not as good as Example 1. The conversion efficiency is slightly improved compared to Comparative Example 1, but far less than Example 1.

[0075] In Comparative Example 4, without the protection of the passivation layer, the charge carriers pass through the metal electrode through the second charge carrier layer and have a local short circuit with the TCO layer, resulting in a significant decrease in voltage and current compared to Example 1.

[0076] Based on the above results, this application is highly operable and can achieve or even surpass the effect of femtosecond laser etching using picosecond laser etching without increasing equipment costs, and achieve or even surpass the effect of flat-top laser etching using Gaussian light. This application can effectively reduce or even eliminate the second etched groove P2 and the third etched groove P3 crater generated by laser etching, improve interface contact, reduce carrier loss, and effectively isolate the metal electrode and perovskite layer in the second etched groove P2, thereby improving the conversion efficiency and stability of the battery module.

[0077] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A perovskite solar cell, characterized by, The device comprises a substrate (1), a bottom electrode layer (2), a first carrier transport layer and perovskite layer (3), a passivation and second carrier transport layer (4) and a top electrode layer (5) which are sequentially stacked on the substrate (1); The bottom electrode layer (2) is provided with a first scribe groove (P1) penetrating the bottom electrode layer (2); The first carrier transport layer and perovskite layer (3) covers the bottom electrode layer (2) and fills the first scribe groove (P1); the first carrier transport layer and perovskite layer (3) is provided with a first 1.5 scribe groove (P1.5) penetrating the first carrier transport layer and perovskite layer (3); The passivation and second carrier transport layer (4) covers the first carrier transport layer and perovskite layer (3) and covers the groove bottom and sidewall of the first 1.5 scribe groove (P1.5), and the passivation and second carrier transport layer (4) is provided with a second scribe groove (P2) in the area of the first 1.5 scribe groove (P1.5), the second scribe groove (P2) penetrating the passivation and second carrier transport layer (4); The top electrode layer (5) covers the passivation and second carrier transport layer (4) and fills the first 1.5 scribe groove (P1.5) and the second scribe groove (P2), and the top electrode layer (5) is further provided with a third scribe groove (P3) penetrating the top electrode layer (5) and the passivation and second carrier transport layer (4); the third scribe groove (P3) is located in the area of the first 1.5 scribe groove (P1.5), and the third scribe groove (P3) is located on the side of the second scribe groove (P2) away from the first scribe groove (P1).

2. The perovskite solar cell according to claim 1, characterized in that, The first 1.5 scribe groove (P1.5) has a line width of 100-300 μm; And / or, the first scribe groove (P1) has a width of 15-50 μm, and the distance between the first scribe groove (P1) and the first 1.5 scribe groove (P1.5) is 50-150 μm; And / or, the second scribe groove (P2) has a line width of 30-200 μm, and the distance between the edge of the second scribe groove (P2) and the edge of the first 1.5 scribe groove (P1.5) close to the second scribe groove (P2) is 10-50 μm; And / or, the third scribe groove (P3) has a line width of 20-50 μm, and the distance between the third scribe groove (P3) and the edge of the first 1.5 scribe groove (P1.5) close to the third scribe groove (P3) is 10-50 μm. 3.The perovskite solar cell of claim 1, wherein, The material of the bottom electrode layer (2) is selected from at least one of ITO, FTO, IZO and AZO; And / or, the first carrier transport layer and perovskite layer (3) comprises a first carrier transport layer and a perovskite layer which are sequentially stacked on the bottom electrode layer (2); And / or, the passivation and second carrier transport layer (4) comprises a passivation layer and a second carrier transport layer which are sequentially stacked on the perovskite layer; And / or, the material of the top electrode layer (5) is selected from at least one of silver, copper, gold, aluminum, ITO and FTO.

4. The perovskite solar cell according to claim 3, characterized in that, The first carrier transport layer is a hole transport layer; And / or, the material of the first carrier transport layer is selected from at least one of Spiro-MeOTAD, nickel oxide, tin oxide, titanium dioxide, zinc oxide, vanadium oxide, molybdenum oxide, tungsten oxide and C60 and derivatives thereof; And / or, the material of the perovskite layer is an ABX3 type perovskite material, wherein A is selected from at least one of Cs, K, Rb, MA and FA, B is selected from at least one of Pb, Sn and Zr, and X is selected from at least one of Br, I and Cl.

5. The perovskite solar cell according to claim 3, characterized in that, The second carrier transport layer is an electron transport layer; And / or, the material of the second carrier transport layer is selected from at least one of nickel oxide, tin oxide, titanium dioxide, zinc oxide, ZnTiO3, tungsten oxide and C60 and derivatives thereof; And / or, the material of the passivation layer is selected from at least one of 1,2-propanediamine hydroiodide, phenethylammonium iodide, ammonium thiocyanate, LiF and Al2O3.

6. A method of producing the perovskite solar cell according to any one of claims 1 to 5, characterized by, Comprising: forming a bottom electrode layer (2) on a substrate, and performing laser scribing on the bottom electrode layer (2) to form a first scribe groove (P1); forming a first carrier transport layer and a perovskite layer (3) on the bottom electrode layer (2), and performing laser scribing on the first carrier transport layer and the perovskite layer (3) to form a first.5 scribe groove (P1.5); forming a passivation and second carrier transport layer (4) on the first carrier transport layer and the perovskite layer (3), and performing laser scribing on the passivation and second carrier transport layer (4) to form a second scribe groove (P2); forming a top electrode layer (5) on the passivation and second carrier transport layer (4), and performing laser scribing on the top electrode layer (5) to form a third scribe groove (P3).

7. The method for preparing a perovskite solar cell according to claim 6, characterized in that, The laser pulse width used for laser scribing is 10-14 ps; And / or, the laser used for laser scribing is Gaussian light.

8. The method for preparing a perovskite solar cell according to claim 6, characterized in that, The preparation method of the perovskite layer in the first carrier transport layer and the perovskite layer (3) is selected from at least one of doctor blade coating, slot coating, spraying, inkjet printing, vacuum evaporation and spin coating; And / or, the preparation method of the bottom electrode, the first carrier transport layer in the first carrier transport layer and the perovskite layer (3), the second carrier transport layer in the passivation and second carrier transport layer (4), the passivation layer in the passivation and second carrier transport layer (4), and the top electrode is independently selected from at least one of doctor blade coating, slot coating, magnetron sputtering, vacuum evaporation and electron beam evaporation.

9. The method for preparing a perovskite solar cell according to claim 6, characterized in that, The ultraviolet wavelength of the laser used for laser scribing is 340-370 nm, or the green wavelength of the laser used for laser scribing is 510-540 nm; And / or, the single pulse energy of the laser used for laser scribing is 10-25 μJ; And / or, the laser used for laser scribing is selected from a solid laser. 10.The method of claim 6, wherein the perovskite solar cell is prepared by the steps of: The laser used for forming the first scribe groove (P1) is incident on the bottom electrode layer (2), and the laser focal point is 0-0.2 mm away from the surface of the bottom electrode layer (2); or the laser used for forming the first scribe groove (P1) is incident on the substrate surface, and the laser focal point is 0-0.2 mm away from the upper surface of the substrate. And / or, the laser incidence direction for forming the first 1.5 scribe groove (P1.5), the second scribe groove (P2), and the third scribe groove (P3) is film surface incidence.

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