Laser modification device and method for perovskite solar cell material

Abstract

A perovskite solar cell material laser modification device disclosed by the present invention comprises an excimer laser light source, the front end of the excimer laser light source is provided with a laser shaping system capable of shaping laser emitted by the excimer laser light source into linear light spots, and the front end of the laser shaping system is provided with a reflector capable of reflecting the shaped laser to a focus lens. The deep ultraviolet excimer laser irradiates a workpiece to process the workpiece, and the temperature sensor is used for detecting the processing temperature. The invention further discloses a laser modification method of the perovskite solar cell material. The laser modification method comprises the following steps: S1, preparing the transparent conductive layer; s2, scribing on the transparent conductive layer; s3, preparing an electron transport layer and a perovskite layer on the transparent conductive layer to obtain a workpiece; and S4, the workpiece is placed on the moving platform, and the deep ultraviolet excimer laser of the linear light spot irradiates the perovskite layer. By adopting the laser modification device and the modification method for the perovskite solar cell material, the defect concentration can be effectively reduced, and the modification processing efficiency is high.

Description

Technical field

[0001] The present invention relates to a laser modification device for perovskite solar cell materials and a laser modification method for perovskite solar cell materials. [Background Technology]

[0002] Perovskite solar cells are generally sandwich-like structures, generally consisting of a central perovskite layer, an electron transport layer (ETL) and a hole transport layer (HTL) on both sides of the perovskite layer, and an outer electrode. The perovskite layer, ETL, and HTL are collectively referred to as functional layers. The perovskite layer usually has an ABX3 structure, where A is generally Cs + 、Ru + , K + 、CH3NH3 + 、C(NH2)3 + 、CH(NH2)2 + A combination of one or more large-sized monovalent cations or groups; B is generally a small-sized divalent cation such as Pb 2+ 、Sn 2+ etc., X is generally such as I - Br - 、Cl - The electron transport layer materials are generally TiO2, ZnO, CdS, SnO2, In2O3, WO x 、CeO、PCBM、C 60 、C 70 The hole transport layer material is generally a combination of one or more materials such as NiO, VO2, MoO3, CuS, CuSCN, CuO, Cu2O, CoO, TAPC, PTAA, PEDOT, Poly TPD, Spiro MeOTAD, etc.

[0003] Because solar cells generate electricity using the photovoltaic effect, one electrode must be made of a transparent material, typically a transparent conductive oxide (TCO) glass. The other electrode is typically a metal electrode or TCO material. TCO materials are typically a combination of one or more materials such as ITO, FTO, AZO, IGO, and BZO. Metal electrodes are typically a combination of one or more materials such as Ag, Cu, Al, Cr, Ti, and Ni.

[0004] During the fabrication of perovskite solar cells, some structures, particularly the perovskite layer, are prepared using methods such as vapor deposition, slot coating, inkjet printing, doctor blade coating, and spin coating. The perovskite layer is often modified using methods such as heat treatment to stabilize the crystal structure, reduce impurity and defect concentrations, and improve the material's optoelectronic properties and stability. Currently, there are also methods for modification using spot laser scanning in the near-ultraviolet, visible, or infrared wavelengths. However, some perovskite layer materials are temperature-sensitive, and heat treatment can easily affect the underlying fabricated devices. Some perovskite layer materials also have low light absorption in certain visible and infrared wavelengths. This can result in some light penetrating the upper perovskite layer and being absorbed by the underlying electron transport layer during processing, affecting processing accuracy. Furthermore, when using spot laser scanning, the material damage threshold, laser energy, frequency, and mechanical structure movement speed interact to limit processing efficiency.

[0005] Therefore, the present invention is just based on above deficiency and produces. [Summary of the invention]

[0006] The present invention aims to overcome the shortcomings of the prior art by providing a laser modification device for perovskite solar cell materials. This device can effectively reduce defect concentrations, inhibit non-radiative carrier recombination and interfacial carrier recombination, and improve photoelectric conversion efficiency. The device utilizes high laser energy and high modification efficiency.

[0007] The present invention also provides a laser modification method for perovskite solar cell materials. The method is used to modify the perovskite solar cell materials, with high modification processing efficiency, low product impurities and defect concentrations, and high product quality.

[0008] A perovskite solar cell material laser modification device includes an excimer laser light source capable of emitting deep ultraviolet excimer laser light. A laser shaping system is provided at the front end of the excimer laser light source, which can shape the laser light emitted by it into a linear light spot. A reflector is provided at the front end of the laser shaping system, which can reflect the shaped laser light to a focusing mirror. After the deep ultraviolet excimer laser penetrates the focusing mirror, it irradiates a workpiece on a movable platform to process the workpiece. The perovskite solar cell material laser modification device also includes a temperature sensor for detecting the processing temperature.

[0009] The deep ultraviolet excimer laser is irradiated onto the perovskite layer of the perovskite solar cell material in a pulsed manner to modify the perovskite layer, and adjacent irradiated areas overlap.

[0010] The laser shaping system comprises a collimating beam expansion system, a linear light spot homogenization system and a projection imaging system which are arranged in sequence.

[0011] An energy attenuation device is also provided between the excimer laser light source and the laser shaping system.

[0012] The perovskite solar cell material laser modification device also includes a microscopic observation device capable of detecting the color and morphology of the processed area.

[0013] A laser modification method for perovskite solar cell materials comprises the following steps:

[0014] S1: preparing a transparent conductive layer on a transparent glass substrate;

[0015] S2: scribing on the transparent conductive layer;

[0016] S3: preparing an electron transport layer and a perovskite layer on the transparent conductive layer obtained in step S2 to obtain a workpiece, wherein the electron transport layer is located between the transparent conductive layer and the perovskite layer;

[0017] S4: The workpiece obtained in step S3 is placed on the movable platform of the laser modification device for perovskite solar cell materials as described above, and the deep ultraviolet excimer laser with a linear spot irradiates the perovskite layer while the movable platform moves, thereby modifying the perovskite layer.

[0018] In step S4 , adjacent irradiation areas of the perovskite layer by the linear light spots overlap.

[0019] The length of the linear light spot is on the order of centimeters, and the width is on the order of micrometers.

[0020] Compared with the prior art, the present invention has the following advantages:

[0021] 1. Deep ultraviolet excimer laser is used as the light source when modifying the perovskite solar cell materials. Currently, most materials used in perovskite solar cell structures have a significantly higher absorption rate for light sources in this band than for light sources in the visible and infrared bands. Therefore, using deep ultraviolet excimer laser as the light source can control the absorption depth and protect the underlying devices prepared in the previous steps.

[0022] 2. Modification of the perovskite layer by deep ultraviolet excimer laser of appropriate energy density can effectively reduce the defect concentration, inhibit the non-radiative recombination of carriers and interface carrier recombination, and improve the photoelectric conversion efficiency.

[0023] 3. The large spot output by the excimer laser light source is conducive to being converted into a linear spot through an optical shaping system. Compared with other high-frequency point spots processed by two-axis scanning, the linear spot of the present invention has a larger single processing area and only needs to scan one axis to complete the processing, thereby improving processing efficiency.

[0024] 4. The length of the linear spot is on the order of meters, and the width is on the order of microns. Therefore, the high-aspect-ratio excimer laser linear spot can be overlapped more closely than the circular spot. In addition, the high-aspect-ratio excimer laser linear spot single-axis scanning does not have the problem of double-axis line wrapping overlap, and the process is simpler.

[0025] 5. Due to the high energy of a single pulse of excimer laser, the linear spot formed by sacrificing part of the energy still has a high enough energy density to meet the processing requirements.

Brief Description of the Drawings

[0026] Figure 1 This is a schematic diagram of the laser modification device for perovskite solar cell materials of the present invention;

[0027] Figure 2 is a schematic diagram after a transparent conductive layer is prepared on a transparent glass substrate;

[0028] Figure 3 This is a schematic diagram after scribing is completed on the transparent conductive layer;

[0029] Figure 4 A schematic diagram of a workpiece obtained by forming an electron transport layer and a perovskite layer on a scribed transparent conductive layer;

[0030] Figure 5 This is a schematic diagram of the process of excimer laser modification on the perovskite layer;

[0031] Figure 6 This is a schematic diagram of an excimer laser linear spot scanning and overlapping adjacent areas;

[0032] Figure 7 This is a schematic diagram after the modification processing is completed on the perovskite layer. [Specific implementation method]

[0033] The present invention will be further described below in conjunction with the accompanying drawings:

[0034] like Figure 1As shown, a laser modification device for perovskite solar cell materials includes an excimer laser light source 1 capable of emitting deep ultraviolet excimer laser light. A laser shaping system 2 is provided at the front end of the excimer laser light source 1, capable of shaping the emitted laser light into a linear spot. A reflector 4 is provided at the front end of the laser shaping system 2, capable of reflecting the shaped laser light toward a focusing mirror 3. The deep ultraviolet excimer laser light passes through the focusing mirror 3 and irradiates a workpiece 6 on a movable platform 5 for processing. The laser modification device for perovskite solar cell materials also includes a temperature sensor 7 for detecting processing temperature. The excimer laser light source 1 emits ultraviolet laser light at the required frequency and energy. The laser shaping system 2 shapes the laser light into a high-aspect-ratio linear laser light. The linear spot of the linear laser light is on the order of centimeters in length and micrometers in width. The linear laser light is reflected by the reflector 4 into a focusing optical path, where it is focused by the focusing mirror 3 to obtain a linear spot size and energy that meets processing requirements. The mobile platform 5 carries the workpiece 6 through the laser irradiation area at a speed that matches the laser frequency and the width after shaping, completing the scanning process and modifying the workpiece 6. An energy attenuation device 9 is also provided between the excimer laser light source 1 and the laser shaping system 2 to control the laser energy of the light source. A temperature sensor 7 monitors the surface processing temperature of the workpiece 6 in real time. The perovskite solar cell material laser modification device also includes a microscopic observation device 10 capable of detecting the color and morphology of the processing area to detect the color and morphology of the processing area. The temperature sensor 7 and the microscopic monitoring device 10 jointly detect the processing status to ensure stable processing production. The workpiece 6 is a perovskite solar cell material. The material is scanned and processed by a deep ultraviolet excimer laser with a linear spot. The single processing area is large, improving processing efficiency, effectively reducing defect concentration, and improving the photoelectric conversion efficiency of the perovskite solar cell material. It can also control the absorption depth to protect the underlying devices of the modified material.

[0035] The deep ultraviolet excimer laser is irradiated onto the perovskite layer 8 of the perovskite solar cell material in a pulsed manner to modify the perovskite layer 8, and adjacent irradiation areas overlap, such as Figure 6 As shown, the overlapping part is indicated by shadow. The laser spot is scanned and irradiated in a pulsed manner. The front and rear linear spots can be overlapped more closely. In addition, the high aspect ratio excimer laser linear spot is scanned in a single axis without the situation of double-axis line-wrap overlap, and the process is simpler.

[0036] like Figures 2 to 7 As shown, a laser modification method for perovskite solar cell materials includes the following steps:

[0037] S1: preparing a transparent conductive layer 200 on a transparent glass substrate 100;

[0038] S2: scribing on the transparent conductive layer 200;

[0039] S3: preparing an electron transport layer 300 and a perovskite layer 8 on the transparent conductive layer 200 obtained in step S2 to obtain a workpiece 6, wherein the electron transport layer 300 is located between the transparent conductive layer 200 and the perovskite layer 8;

[0040] S4: The workpiece 6 obtained in step S3 is placed on the mobile platform 5 of the perovskite solar cell material laser modification device described above. The deep ultraviolet excimer laser 72 in the form of a linear spot irradiates the perovskite layer 8 during the movement of the mobile platform 5, thereby modifying the perovskite layer 8. Specifically, the surface of the perovskite layer 8 is placed at the focus of the excimer laser for modification processing. First, the first spot position is determined. The perovskite layer 8 is irradiated with the excimer laser linear spot according to the energy density required for the modification of the perovskite layer 8 of different products. The first spot irradiation position is the first modification processing area. As the mobile platform 5 moves, the linear spot moves to the next modification processing area for irradiation. This process is repeated to complete the modification processing of the entire perovskite layer 8. To ensure that the entire product is better modified, adjacent irradiation areas should partially overlap. This requirement can be met by partially overlapping the two linear spot irradiations. This process is repeated until the modification of the entire solar cell material is completed.

Claims

1. A laser modification device for perovskite solar cell materials, characterized by: The invention comprises an excimer laser light source (1) capable of emitting deep ultraviolet excimer laser light, wherein the front end of the excimer laser light source (1) is provided with a laser shaping system (2) capable of shaping the laser light emitted by the excimer laser light source into a linear light spot, and the front end of the laser shaping system (2) is provided with a reflecting mirror (4) capable of reflecting the shaped laser light to a focusing mirror (3), and the deep ultraviolet excimer laser light penetrates the focusing mirror (3) and then irradiates a workpiece (6) on a moving platform (5) to process the workpiece (6), and the perovskite solar cell material laser modification device further comprises a temperature sensor (7) for detecting the processing temperature.

2. The laser modification device for perovskite solar cell materials according to claim 1, characterized in that: The deep ultraviolet excimer laser is irradiated onto the perovskite layer (8) of the perovskite solar cell material in a pulsed manner to modify the perovskite layer (8), and adjacent irradiated areas overlap.

3. The laser modification device for perovskite solar cell materials according to claim 1, characterized in that: The laser shaping system (2) comprises a collimating beam expansion system (21), a linear light spot homogenization system (22), and a projection imaging system (23) which are arranged in sequence.

4. The laser modification device for perovskite solar cell materials according to claim 1, characterized in that: An energy attenuation device (9) is also provided between the excimer laser light source (1) and the laser shaping system (2).

5. The laser modification device for perovskite solar cell materials according to claim 1, characterized in that: It also includes a microscopic observation device (10) capable of detecting the color and appearance of the processed area.

6. A laser modification method for perovskite solar cell materials, characterized in that: The steps include: S1: preparing a transparent conductive layer (200) on a transparent glass substrate (100); S2: scribing on the transparent conductive layer (200); S3: preparing an electron transport layer (300) and a perovskite layer (8) on the transparent conductive layer (200) obtained in step S2 to obtain a workpiece (6), wherein the electron transport layer (300) is located between the transparent conductive layer (200) and the perovskite layer (8); S4: The workpiece (6) obtained in step S3 is placed on the movable platform (5) of the laser modification device for perovskite solar cell materials according to any one of claims 1 to 5, and the deep ultraviolet excimer laser with a linear spot is irradiated on the perovskite layer (8) during the movement of the movable platform (5), thereby modifying the perovskite layer (8).

7. The laser modification method for perovskite solar cell materials according to claim 6, characterized in that: In step S4, the adjacent irradiation areas of the perovskite layer (8) are overlapped by the linear light spots.

8. The laser modification method for perovskite solar cell materials according to claim 6, characterized in that: The length of the linear light spot is on the order of centimeters, and the width is on the order of micrometers.

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