A method and system for fabricating perovskite solar cell optoelectronic modules

Abstract

This invention discloses a method for fabricating a perovskite solar cell optoelectronic module. After depositing the oxide layer and before P2 laser scribing, a pre-coating step is added: a heat-absorbing layer is pre-coated onto the oxide layer and cured. The heat-absorbing layer has a conduction band level greater than -5.43 eV and a conductivity greater than 10. ‑6 The material has an Ω / m density, and the heat-absorbing layer covers the P2 laser scribing area; the P2 laser scribing is performed using a laser in the 355-2000nm wavelength band. This invention can improve the long-term operational stability of the equipment and reduce equipment costs, thereby meeting the needs of large-format, high-efficiency production and enabling the mass production of this type of perovskite solar cell.

Description

Technical Field

[0001] This invention relates to the field of perovskite solar cell optoelectronic module fabrication technology, and in particular to a method and system for fabricating perovskite solar cell optoelectronic modules. Background Technology

[0002] A special perovskite solar cell structure consists of, from bottom to top, a substrate, a front electrode layer, an electron transport layer, an isolation layer, a hole transport layer, and a carbon electrode. Finally, the perovskite active material is infiltrated into the marked cell and left to dry to complete the fabrication of the perovskite solar cell.

[0003] In manufacturing large-area battery substrates for this type of battery, the laser etching process is completed in three steps. For example... Figure 1 As shown, the process involves three steps: First, laser LA1 is used to etch away the front electrode of region S1 on the substrate with the front electrode layer, dividing the front electrode layer into independent electrodes; this is called P1 laser scribing. Second, an electron transport layer, an isolation layer, and a hole transport layer are coated on the scribed P1 electrode. Laser LA2 is then used to etch away the electron transport layer, isolation layer, and hole transport layer of region S2, dividing these layers into regions without damaging the front electrode layer; this is called P2 scribing. Third, a carbon electrode is coated. Laser LA3 is then used to etch away the electron transport layer, isolation layer, hole transport layer, and carbon electrode within the selected region, dividing these layers into regions without damaging the front electrode; this is called the P3 process. Finally, perovskite active material is infiltrated onto the scribed cell to complete the battery manufacturing process.

[0004] In the existing P2 scribing process, the laser needs to etch the oxide layer, which serves as both the electron transport layer and the isolation layer, while ensuring that the laser does not damage the underlying front electrode. Furthermore, due to the presence of plate-like and spherical particles in the carbon electrode slurry, a wide scribing spot is required in the P2 process to ensure that the carbon electrode particles fall within the etched lines to achieve conductivity between the upper and lower electrodes. This places extremely high demands on the laser power, the precision and stability of mechanical components, and maintenance, inevitably increasing costs significantly and making it unsuitable for mass production. Therefore, given the lack of a suitable mass production solution, this type of perovskite solar cell has not yet achieved mass production. Summary of the Invention

[0005] The main objective of this invention is to provide a method and system for preparing perovskite solar cell optoelectronic modules, which can improve the long-term operational stability of the equipment, reduce equipment costs, and thus meet the needs of mass production.

[0006] The technical solution adopted in this invention is: a method for preparing a perovskite solar cell optoelectronic module, including the steps of P1 laser scribing, depositing an oxide layer, P2 laser scribing, depositing an upper electrode, P3 laser scribing, and infiltrating perovskite active material;

[0007] After depositing the oxide layer and before P2 laser scribing, a pre-coating step is added: a heat-absorbing layer is pre-coated on the oxide layer and cured. The heat-absorbing layer has a conduction band energy level greater than -5.43 eV and a conductivity greater than 10. -6 The material has an Ω / m ratio, and the heat-absorbing layer covers the P2 laser scribing area;

[0008] P2 laser scribing uses a laser in the 355-2000nm wavelength range to complete the laser scribing.

[0009] According to the above scheme, the material of the heat-absorbing layer is the same as that of the upper electrode; during pre-coating, the heat-absorbing layer is either fully pre-coated or partially pre-coated, and the partially pre-coated area covers the P2 laser scribing area; when depositing the upper electrode, if there is a heat-absorbing layer remaining after P2 laser scribing, the heat-absorbing layer and the entire upper electrode material to be deposited together constitute the upper electrode.

[0010] According to the above scheme, the heat-absorbing layer material is different from the upper electrode; during pre-coating, the heat-absorbing layer is fully pre-coated or partially pre-coated, and the partially pre-coated area covers the P2 laser scribing area; after P2 laser scribing and before depositing the upper electrode, the heat-absorbing layer is removed.

[0011] According to the above scheme, the thickness of the heat-absorbing layer is 20%-80% of the total thickness of the upper electrode.

[0012] According to the above scheme, the material of the upper electrode is carbon.

[0013] According to the above scheme, the laser marking adopts a method of parallel focusing optical path of multiple lasers, specifically: multiple lasers, each laser is equipped with a focusing lens, the light spots formed after the laser emitted by each laser passes through the corresponding focusing lens are independent of each other, and multiple lasers work simultaneously.

[0014] According to the above scheme, during laser marking, the laser is fixed and the material carrying unit moves continuously with the material to complete the laser marking.

[0015] According to the above scheme, the wavelength of the laser is 500-1100nm.

[0016] According to the above scheme, between the oxide layer deposition step and the pre-coating step, there is also a hole transport layer deposition step.

[0017] A fabrication system for a method of fabricating a perovskite solar cell optoelectronic module, the fabrication system comprising a laser processing device, the laser processing device consisting of a laser and a focusing lens.

[0018] The beneficial effects of this invention are:

[0019] 1. By pre-coating a heat-absorbing layer before P2 laser scribing, the heat-absorbing layer has an extremely high laser absorption rate in the area. The area irradiated by the laser can heat up rapidly and transfer the heat to the P2 target film layer, achieving the heating expansion and shedding of the target area to complete the scribing target. This allows P2 laser scribing to use lasers of all wavelengths, ensuring optimal process results. This also allows for the selection of lasers with high stability and low cost, reducing equipment costs and increasing the long-term operational stability of the equipment, thereby meeting the needs of large-format, high-efficiency production and enabling the mass production of this type of perovskite solar cell.

[0020] 2. To further simplify the process and reduce costs, the same material as the top electrode is used as the heat-absorbing layer. In this way, the heat-absorbing layer not only helps the target area to heat up and expand during P2 laser scribing to complete the scribing target, but also does not need to be removed. It can be directly combined with the material deposited in the subsequent top electrode to form the top electrode. Attached Figure Description

[0021] The present invention will be further described below with reference to the accompanying drawings and embodiments. In the accompanying drawings:

[0022] Figure 1 This is a flowchart of the traditional laser scribing process.

[0023] Figure 2 The graph shows the transmittance and difference curves of materials P1 and P2 for different wavelengths of light.

[0024] Figure 3 This is a flowchart of a laser scribing process according to an embodiment of the present invention.

[0025] Figure 4 This is a flowchart illustrating laser scribing according to another embodiment of the present invention.

[0026] Figure 5 This is a process effect diagram of an embodiment of the present invention.

[0027] Figure 6 This is a diagram showing the process effect of traditional techniques in comparison.

[0028] In the figure: 1-conductive substrate, 2-lower electrode, 3-oxide layer, 4-upper electrode, 5-heat-absorbing layer. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0030] In order to provide a good mass production solution that is inexpensive and stable, this application proposes a method for preparing perovskite solar cell optoelectronic modules, including the steps of P1 laser scribing, deposition of an oxide layer, P2 laser scribing, deposition of an upper electrode, P3 laser scribing, and infiltration of perovskite active material.

[0031] The improvement of this invention lies in the addition of a pre-coating step after depositing the oxide layer and before P2 laser scribing: a heat-absorbing layer is pre-coated on the oxide layer and cured. The heat-absorbing layer has a conduction band level greater than -5.43 eV and a conductivity greater than 10. -6 The material has an Ω / m ratio, and the heat-absorbing layer covers the P2 laser scribing area. The P2 laser scribing is completed using a laser in the 355-2000nm wavelength band, preferably a laser with a wavelength of 500-1100nm.

[0032] By pre-coating a heat-absorbing layer before P2 laser scribing, the heat-absorbing layer exhibits extremely high laser absorption in the affected area. The laser-irradiated area rapidly heats up, and this heat is transferred to the P2 target film layer, causing the target area to expand and detach, thus completing the scribing target. Therefore, P2 laser scribing can utilize lasers of all wavelengths, ensuring optimal process results. This allows for the selection of stable and inexpensive lasers, reducing equipment costs and increasing long-term operational stability, thereby meeting the needs of large-format, high-efficiency production and enabling mass production of this type of perovskite solar cell.

[0033] The applicant's research found that, because the absorption curves of the front electrode material and the film layers that require laser action in the P2 etching process are similar and have high transmittance for most wavelengths of laser light, the transmittance of different film layers for different wavelengths of light is shown in the figure. Figure 2 In the figure, l1 represents the transmittance of material P1, l2 represents the transmittance of material P2, and Δl represents the difference between the two. The data shows that the transmittance of the materials exceeds 50% in the 500–1700 nm wavelength range, while in the 355 nm wavelength range, the transmittance difference between material P2 and material P1 is at most approximately 40%. Following this principle, only a high-cost ultraviolet laser could be selected. However, using the method of this application, because the heat-absorbing layer has extremely high laser absorption in this region, most of the laser energy is absorbed by the heat-absorbing layer during the scribing process. Therefore, it is not necessary to consider whether the transmittance difference between materials P1 and P2 meets the scribing requirements; that is, a laser of any wavelength can complete P2 laser scribing. This allows for the selection of a lower-cost, more stable laser.

[0034] The principle of this invention lies in pre-treating the film layer before the P2 material arrives, enabling the P2 film layer to efficiently receive laser energy in the 355-2000nm wavelength band, preferably a laser in the 500-1100nm wavelength band. Lasers in the 500-1100nm wavelength band can easily achieve high power due to their inherent characteristics; therefore, a single laser in this band can complete a P2 scribe line several hundred micrometers wide. Furthermore, lasers in this band have significantly stronger long-term stability than ultraviolet lasers, and even multiple lasers in this band will not affect the long-term operational stability of the equipment. Therefore, when performing P2 laser scribe lines, a method using multiple lasers in parallel focusing within the 355-2000nm (especially 500-1100nm) wavelength band, which offers relatively more stable performance and lower equipment costs, can be employed. Specifically, multiple lasers are used, each equipped with a focusing lens. The laser beam emitted by each laser forms an independent spot after passing through its corresponding focusing lens, and multiple lasers operate simultaneously. Further research by the applicant revealed that due to the wide etched line width in the P2 process, extremely high laser power is required to meet certain production capacity. Therefore, a spot-stacking scheme is the only viable option: using a galvanometer to control the reciprocating motion of the laser spot, closely aligning the etched lines to form a wider etched line on the solar cell. This spot-stacking scheme requires a series of optical components such as reflectors, beam expanders, shaping mirrors, galvanometers, and field mirrors. The overall optical path is long, placing extremely high demands on the precision and stability of mechanical components, making maintenance difficult, and requiring high splicing accuracy. However, the pre-coating method described in this application eliminates the need for a spot-stacking scheme. Instead, a multi-laser parallel focusing optical path is used, significantly simplifying the optical path and improving processing accuracy compared to the spot-stacking scheme.

[0035] Furthermore, during laser scribing, the laser remains stationary while the material-carrying unit continuously moves with the material to complete the laser scribing (spot stitching typically involves step-by-step movement), significantly improving processing speed and accuracy. Simultaneously, the multi-path parallel scheme greatly simplifies the optical path compared to the spot stitching scheme; the laser only needs to pass through a focusing lens, unlike the complex optical path of the galvanometer-stitching scheme which requires beam expansion and shaping before entering the galvanometer and field lens. This simplified optical path reduces debugging workload, increases long-term equipment stability, and reduces equipment costs.

[0036] Preferably, the material of the heat-absorbing layer can be the same as that of the upper electrode. During pre-coating, the heat-absorbing layer can be fully pre-coated or partially pre-coated, with the partially pre-coated area covering the P2 laser-marked area; if fully pre-coated, the pre-coating effect is as follows: Figure 3 As shown, if it is a local pre-coating, the pre-coating effect is as follows: Figure 4As shown, generally speaking, if it is a partial pre-coating, after the P2 laser scribing step, there will be a small amount of heat-absorbing layer remaining on the oxide layer, but there may be none. Regardless of whether it is a full pre-coating or a partial pre-coating, if there is a heat-absorbing layer remaining after the P2 laser scribing when depositing the top electrode, the heat-absorbing layer and the entirety of the top electrode material to be deposited are considered as the top electrode.

[0037] Preferably, the heat-absorbing layer material may be different from the upper electrode. During pre-coating, the heat-absorbing layer may be fully pre-coated or partially pre-coated, with the partially pre-coated area covering the P2 laser scribing area. The heat-absorbing layer is removed after the P2 laser scribing and before the upper electrode is deposited.

[0038] Preferably, the upper electrode material is typically carbon.

[0039] The thickness of the heat-absorbing layer is 20%-80% of the total thickness of the upper electrode. If it is less than 20% of the total thickness of the upper electrode, the light absorption efficiency will be low and the process target cannot be achieved; if it is more than 80% of the total thickness of the upper electrode, there will be less space reserved when coating the next electrode layer, resulting in poor conductivity between the upper and lower electrodes of the battery.

[0040] Furthermore, between the oxide layer deposition step and the pre-coating step, a hole transport layer deposition step is also included. For some perovskite solar cells, it may be necessary to fabricate a hole transport layer between the oxide layer and the top electrode.

[0041] This invention also provides a fabrication system for the fabrication of the perovskite solar cell optoelectronic module. This fabrication system includes a laser processing device, which consists of a laser and a focusing lens. Due to the pre-coating process, the wavelength restrictions can be relaxed, allowing for the selection of a highly stable laser. This enables the selection of a stable and inexpensive laser, reducing equipment costs and increasing the long-term operational stability of the equipment. This meets the needs of large-format, high-efficiency production, enabling the mass production of this type of perovskite solar cell.

[0042] In addition, a technical solution of multiple lasers operating in parallel can be adopted, which has high processing accuracy and fast processing speed.

[0043] The complete process flow of a specific embodiment and comparative example is given below.

[0044] Example:

[0045] like Figure 3 and Figure 4 As shown.

[0046] 1. Prepare a transparent conductive substrate 1. The conductive substrate 1 is a conductive glass with one side being FTO or ITO. FTO or ITO can be used as the front electrode layer of the perovskite solar cell, i.e., the lower electrode 2.

[0047] 2. P1 laser scribing: The lower electrode 2 of S1 in the selected area is divided into independent electrodes using infrared laser LA1. This step is called P1 laser scribing.

[0048] 3. Deposition of oxide layer: The substrate is heated to 450°C, TiO2 active material is sprayed and then the substrate is cooled to room temperature to form a dense TiO2 layer; a TiO2 slurry is coated on the substrate coated with the dense TiO2 layer by spraying or scraping, and the substrate is heated to 500°C and held for 30 minutes to form a mesoporous TiO2 layer. The above two layers serve as the electron transport layer of the perovskite solar cell. SnO2 can also be used as a substitute for this material.

[0049] A ZrO2 slurry is coated on a substrate with a mesoporous TiO2 layer by spraying or scraping. The substrate is heated to 500°C and held for 30 minutes to form a mesoporous ZrO2 layer. This layer serves as an isolation layer to prevent short circuit between the positive and negative electrodes of the battery.

[0050] A hole transport layer is coated on a substrate coated with TiO2 and ZrO2 by spraying or scraping. The above steps complete the fabrication of the oxide layer 3 (electron transport layer + isolation layer) and hole transport layer of the perovskite solar cell.

[0051] 4. Pre-coating step: On the incoming material that has been coated with oxide layer and hole transport layer, a thin heat-absorbing layer 5 is pre-coated by screen printing or coating with active material, or a thin heat-absorbing layer 5 is coated only in the area to be scribed. After drying, heat to 400℃ to complete the coating of heat-absorbing layer 5, and the preparation work for P2 laser scribing is completed.

[0052] In this embodiment, the heat-absorbing layer 5 is made of the same carbon material as the carbon electrode material. Alternatively, the heat-absorbing layer 5 may have a conduction band level greater than -5.43 eV and a conductivity greater than 10. -6 Material replacement for Ω / m.

[0053] 5. P2 Laser Scribing: The oxide layer of S2 within the selected area is etched using an infrared laser LA2, without damaging the underlying front electrode layer. This step is called P2 laser scribing. P2 laser scribing can be performed using a multi-laser parallel focusing method, that is, multiple lasers (each laser equipped with a focusing lens) work simultaneously to scribing, with each laser spot scribing one line.

[0054] 6. Deposition of the upper electrode: On the raw material with P2 laser scribing completed, the upper electrode 4 is coated by screen printing or active material coating. After drying at 70°C, it is heated to 400°C to complete the fabrication of the upper electrode 4.

[0055] 7. P3 laser scribing: Using an infrared laser LA3, the oxide layer 3 and the upper electrode 4 in the selected area S3 are etched to form an independent cell, while the lower electrode 2 of the underlying layer of the etched area is not damaged. This step is called P3 laser scribing.

[0056] 8. Infiltration of perovskite active material: Perovskite active material is infiltrated into the marked solar cell. Since both TiO2 and ZrO2 layers are mesoporous materials, the perovskite active material can be easily infiltrated. After standing, it is dried at 50°C to complete the manufacturing of perovskite solar cells.

[0057] The wavelength of the laser is not limited to infrared lasers; lasers in the 355-2000nm band are preferred, and lasers in the 500-1100nm band are even more preferred, as all can heat the pre-coated heat-absorbing layer 5. Considering cost and laser stability, a 1064nm infrared laser is the optimal choice. The pre-coated heat-absorbing layer 5 has high absorption efficiency for this wavelength of laser, is easily heated, and conducts heat to the oxide layer, causing both the oxide layer and the heat-absorbing layer 5 to detach simultaneously, thus achieving the laser scribing process effect.

[0058] Figure 5 This is a diagram showing the effect of P2 laser scribing in this embodiment. As can be seen from the diagram, the front electrode layer is undamaged and fully exposed, and there are no oxide layers or hole transport layers remaining on the front electrode layer.

[0059] Comparative Example

[0060] Traditional crafts, such as Figure 1 As shown.

[0061] 1. Prepare a transparent conductive substrate. The substrate is a conductive glass with one side being FTO or ITO. FTO or ITO can be used as the front electrode layer of the perovskite solar cell.

[0062] 2. P1 laser scribing: Using infrared laser LA1, the front electrode of S1 within the selected area is divided into independent electrodes.

[0063] 3. Deposition of oxide layer: The substrate is heated to 450°C, TiO2 active material is sprayed and then the substrate is cooled to room temperature to form a dense TiO2 layer; a TiO2 slurry is coated on the substrate coated with the dense TiO2 layer by spraying or scraping, and the substrate is heated to 500°C and held for 30 minutes to form a mesoporous TiO2 layer. The above two layers serve as the electron transport layer of the perovskite solar cell. SnO2 can also be used as a substitute for this material.

[0064] A ZrO2 slurry is coated on a substrate with a mesoporous TiO2 layer by spraying or scraping. The substrate is heated to 500°C and held for 30 minutes to form a mesoporous ZrO2 layer. This layer serves as an isolation layer to prevent short circuit between the positive and negative electrodes of the battery.

[0065] A hole transport layer is coated on a substrate coated with TiO2 and ZrO2 by spraying or scraping. The above steps complete the fabrication of the oxide layer and hole transport layer of the perovskite solar cell.

[0066] 4. P2 laser scribing: The oxide layer of S2 in the selected area is etched using an infrared laser LA2, while the front electrode layer under the etched area is not damaged. This step is called P2 laser scribing.

[0067] 5. Electrode deposition: On the raw material with P2 laser scribing completed, carbon electrode coating is completed using screen printing or active material coating. After drying at 70°C, it is heated to 400°C to complete the carbon electrode manufacturing.

[0068] 6. P3 laser scribing: Using an infrared laser LA3, the oxide layer and carbon electrode layer in the selected area S3 are etched to form an independent cell, while the front electrode layer under the etched area is not damaged. This step is called P3 aurora scribing.

[0069] 7. Infiltration of perovskite active material: Perovskite active material is infiltrated into the marked solar cell. Since both TiO2 and ZrO2 layers are mesoporous materials, the perovskite active material can be easily infiltrated. After standing, it is dried at 50°C to complete the manufacturing of perovskite solar cells.

[0070] Figure 6 This is a diagram showing the effect of P2 laser scribing on the comparative model. As can be seen from the diagram, there are residues of oxide layer and hole transport layer on the front electrode layer.

[0071] Comparison of process effects revealed that, after adding the pre-coating step, the heat-absorbing layer exhibits extremely high laser absorption in the affected area. The laser-irradiated area rapidly heats up, which is simultaneously transferred to the P2 target film layer, causing the target area to expand and detach, thus completing the laser marking. This achieves good removal of both the heat-absorbing layer and the P2 film layer while ensuring the front electrode layer remains intact and fully exposed. Furthermore, the remaining heat-absorbing layer, if it is a carbon electrode layer, can fuse with the newly coated carbon electrode layer to form a new carbon electrode layer, without affecting the final battery structure. This invention optimizes the P2 laser marking process without compromising the final battery performance. Replacing the expensive and unstable ultraviolet laser with a cheaper and more stable one, and replacing the complex galvanometer splicing scheme with a single-path focusing lens scheme, significantly reduces the number of optical components and the laser path length, greatly lowering the requirements for mechanical precision and stability, and significantly reducing maintenance and debugging difficulty.

[0072] It should be understood that those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims.

Claims

1. A method for fabricating a perovskite solar cell optoelectronic module, comprising the steps of P1 laser scribing, deposition of an oxide layer, P2 laser scribing, deposition of an upper electrode, P3 laser scribing, and infiltration of perovskite active material; characterized in that, After depositing the oxide layer and before P2 laser scribing, a pre-coating step is added: a heat-absorbing layer is pre-coated on the oxide layer and cured. The heat-absorbing layer has a conduction band energy level greater than -5.43 eV and a conductivity greater than 10. -6 The material has an Ω / m ratio, and the heat-absorbing layer covers the P2 laser scribing area; P2 laser scribing uses a laser in the 355-2000nm wavelength range to complete the laser scribing.

2. The preparation method according to claim 1, characterized in that, The heat-absorbing layer is made of the same material as the upper electrode. During pre-coating, the heat-absorbing layer is either fully pre-coated or partially pre-coated, with the partially pre-coated area covering the P2 laser scribing area. When depositing the upper electrode, if there is a heat-absorbing layer remaining after the P2 laser scribing, the heat-absorbing layer and the entire upper electrode material to be deposited together constitute the upper electrode.

3. The preparation method according to claim 1, characterized in that, The heat-absorbing layer material is different from the upper electrode; during pre-coating, the heat-absorbing layer is pre-coated entirely or partially, with the partially pre-coated area covering the P2 laser scribing area; after the P2 laser scribing and before depositing the upper electrode, the heat-absorbing layer is removed.

4. The preparation method according to any one of claims 1 to 3, characterized in that, The thickness of the heat-absorbing layer is 20%-80% of the total thickness of the upper electrode.

5. The preparation method according to any one of claims 1 to 3, characterized in that, The material of the upper electrode is carbon.

6. The preparation method according to claim 1, characterized in that, The laser marking method employs a multi-laser parallel focusing optical path approach, specifically: Multiple lasers, each equipped with a focusing lens, and the light spots formed after the laser emitted by each laser passes through the corresponding focusing lens are independent of each other, with multiple lasers working simultaneously.

7. The preparation method according to claim 6, characterized in that, During the laser scribing process, the laser is kept stationary while the material carrying unit moves continuously with the material to complete the laser scribing.

8. The preparation method according to claim 1, characterized in that, The wavelength of the laser is 500-1100nm.

9. The preparation method according to claim 1, characterized in that, Between the oxide deposition step and the pre-coating step, there is also a hole transport layer deposition step.

10. A fabrication system for a method of fabricating a perovskite solar cell photovoltaic module according to any one of claims 1 to 9, characterized in that: This preparation system includes laser processing equipment, which consists of a laser and a focusing lens.

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