Laser scribing method and system for perovskite solar cell and cell

Abstract

The invention relates to a laser scribing method and system for a perovskite solar cell and the cell, and the method comprises the following steps: 1, P1 scribing: employing picosecond laser to execute a P1 scribing process on a transparent conductive layer, and forming a first isolation groove; 2, P2 scribing: sequentially preparing a hole transport layer, a perovskite active layer and an electron transport layer, then executing a P2 scribing process, and carrying out back incidence from the substrate glass side by adopting picosecond laser to form a second isolation groove exposing part of the transparent conductive layer; and 3, P3 scribing: after the metal electrode layer is prepared, executing a P3 scribing process, and performing front incidence from the metal electrode side by adopting picosecond laser to form a third isolation groove. According to the method, the total dead zone width is remarkably reduced, the total dead zone width is controlled within the range of 100-200 microns through collaborative optimization of the three procedures, the total dead zone width is remarkably reduced compared with the prior art, and the geometric filling factor and the photoelectric conversion efficiency of the assembly are improved.

Description

Technical Field

[0001] This invention relates to the field of perovskite solar cell technology, and in particular to a laser scribing method, system and cell for perovskite solar cells. Background Technology

[0002] Perovskite solar modules have become one of the fastest-growing emerging technologies in the photovoltaic field due to their high photoelectric conversion efficiency (over 27% in laboratory single-cell efficiency and over 24% in module efficiency) and low manufacturing cost (material cost is only 1 / 5 of that of crystalline silicon modules). Laser scribing is the core process for series interconnection of perovskite modules. It achieves series connection of sub-cells through three processes: P1 (segmentation of transparent conductive layer), P2 (interconnection of active layer / functional layer), and P3 (segmentation of back electrode). The process precision (dead zone width, functional layer damage rate, defect rate) directly determines the geometric fill factor (GFF), series resistance (Rs), and long-term stability of the module.

[0003] The current technological bottlenecks in the industry are concentrated in four aspects: First, it is difficult to balance "narrow dead zone" and "segmentation reliability" (existing dead zones are mostly >150μm, and the conductivity of large-area modules is prone to exceed the standard); second, frontal incident P2 / P3 leads to damage to the underlying functional layer (ITO / SnO2), increasing series resistance by >15%; third, defect control relies on "post-inspection / packaging remediation," which cannot prevent damage from the source; and fourth, single-process optimization has not formed a full-process collaboration, resulting in a mass production yield of <92%. Although existing technologies have made breakthroughs in dead zone reduction, defect detection, and packaging protection, they have not formed a complete solution of "pre-process optimization + full-process collaboration," which restricts the commercialization of modules.

[0004] The existing solutions are listed below:

[0005] 1. A fabrication scheme for perovskite solar cells with reduced dead zones (CN119789674A)

[0006] A dead zone optimization scheme of "removing P2 scribe line + series connection of conductive lines" is proposed: P1 scribe line (30-80μm) separates conductive blocks, and "conductive line + insulating layer" is prepared at the edge. P3 scribe line (20-80μm) is distributed opposite to the conductive blocks. Sub-cells are connected in series through external conductive lines. The dead zone width is 100-180μm and the GFF is 96.8-99.0%.

[0007] Using only a single laser for P1 / P3 etching cannot adapt to different substrate sizes (small area dead zone > 30μm, large area conductivity > 3%); eliminating P2 etching relies on additional insulating layers / conductive lines, increasing process costs by 15%, and does not utilize incident direction optimization to reduce damage.

[0008] 2. Femtosecond laser P1-P3 parameter optimization scheme (Chandler, CW et al., Surface and Interface Analysis, 2025, 57(9):892-901)

[0009] Using only a single wavelength laser, the uneven energy distribution in large-area components (≥1.2m) leads to a conductivity >2%; both P2 / P3 are front-incident, resulting in an ITO damage rate of 5-8%, and the problem of Cu electrode tearing remains unresolved.

[0010] 3. Repair solution for abnormalities in perovskite laser scribing (CN119677368A)

[0011] The closed-loop solution of "detection-repair-inspection" is as follows: CCD camera acquires abnormal images (such as P1 not being broken, P3 remaining), and repair parameters are matched according to the process (P1 energy 4-8%, P3 energy 5-15%). After repair, the component efficiency is increased from 7.48% to 10.59%, and there is no significant decay in stability at 85℃ / 85% RH.

[0012] This is considered "post-treatment repair" and cannot prevent ITO / SnO2 damage (the ITO damage rate is still >12% after repair); the laser type and incident direction are not optimized, and the repair relies on high power, which exacerbates the thermal effects.

[0013] 4. Marking and Groove Protection Encapsulation Solution (CN117596904A)

[0014] Defect masking during encapsulation: The back electrode layer is provided with a 2-10μm polymer planarization layer (filling the P2 / P3 trenches), covered with a 0.05-1.5μm inorganic insulating layer (water and oxygen shielding), and P3 is treated with a femtosecond laser (30-100μm). The stability attenuation rate is reduced to 20% at 85℃ / 85%RH.

[0015] This is a "passive remedy" because the laser process was not optimized (P3 Cu tear rate > 5%); the addition of a planarization layer / insulation layer increased costs by 20%, and mass production compatibility was poor.

[0016] In summary, the shortcomings of existing technologies are as follows:

[0017] 1. Limited laser type leads to insufficient adaptability:

[0018] Existing technologies 1 and 2 both use a single wavelength laser (unspecified or only 532nm), which cannot adapt to different sized substrates like the present invention through "dynamic selection of 532nm green light / 1064nm infrared light". That is, the dead zone of small area components is difficult to be less than 200μm, and the conductivity of large area components is greater than 2% due to uneven energy.

[0019] 2. Limited incident direction causes damage to the underlying layer:

[0020] Existing technologies 2 to 4 use front-side incident light throughout the entire process, failing to utilize the "material selective absorption" characteristics of back-side incident light (ITO absorption rate <5%, perovskite absorption rate >90%) of this invention, resulting in ITO damage rate generally >5%, requiring the encapsulation layer of existing technology 4 to remedy the situation (increasing costs by 20%).

[0021] 3. Defect control mode lag affects stability:

[0022] Existing technologies 3 and 4 rely on "post-treatment repair / encapsulation cover-up," which cannot avoid defects from the source: P3 Cu electrode tearing rate >10%, SnO2 decomposition rate >20%, 85℃ / 85% RH stability decay rate >20%; the present invention can control the tearing rate to <1% through "pre-treatment parameter optimization."

[0023] 4. Lack of process coordination leads to cost conflicts:

[0024] Existing technologies 1 and 4 only optimize a single link: (1) additional conductive lines are required, which increases the cost by 15%, and existing technology 4 adds a packaging layer, which increases the cost by 20%; neither has formed the full-process synergy of "laser selection - incident direction - dead zone overlap" of the present invention, and the total dead zone is still >150μm.

[0025] In view of the above-mentioned shortcomings, the designer has actively researched and innovated in order to create a laser scribing method, system and cell for perovskite solar cells, making them more industrially valuable. Summary of the Invention

[0026] To address the aforementioned technical problems, the present invention aims to provide a laser scribing method, system, and cell for perovskite solar cells.

[0027] To achieve the above objectives, the present invention adopts the following technical solution:

[0028] One of the objectives of this invention is:

[0029] A laser scribing method for perovskite solar cells includes the following steps:

[0030] Step 1, P1 scribing: A picosecond laser is used to perform the P1 scribing process on the transparent conductive layer to form the first isolation groove;

[0031] Step 2: P2 scribing: After the hole transport layer, perovskite active layer and electron transport layer are prepared in sequence, the P2 scribing process is performed. A picosecond laser is used to shine on the back side of the substrate glass to form a second isolation groove that exposes part of the transparent conductive layer.

[0032] Step 3: P3 scribing: After the metal electrode layer is prepared, the P3 scribing process is performed. A picosecond laser is used to shine on the metal electrode from the front to form the third isolation groove.

[0033] The first, second, and third isolation trenches overlap in the direction perpendicular to the substrate, with the total overlap area accounting for 20% to 30% of the area of ​​a single isolation trench, thus making the total dead zone width 100 to 200 μm.

[0034] As a further improvement of the present invention, in step 1, the working conditions for marking P1 are dynamically selected based on the area of ​​the target battery:

[0035] When the area of ​​the target battery is less than 0.5m² 2 At that time, a picosecond green laser with a wavelength of 532nm was selected, with a power of 1.2 to 1.8W, a scanning speed of 1500 to 2500mm / s, and a scribing width of 10 to 20μm;

[0036] When the area of ​​the target battery is greater than or equal to 1.2m² 2 At that time, a picosecond infrared laser with a wavelength of 1064nm was selected, with a power of 1.8 to 2.4W, a scanning speed of 1000 to 2000mm / s, and pulse train mode was enabled, with a line width of 30 to 60μm.

[0037] As a further improvement of the present invention, in step 2, the working conditions for drawing the line P2 are as follows:

[0038] A picosecond green laser with a wavelength of 532nm was selected, with a power of 0.8–1.5W, a scanning speed of 2000–4000mm / s, and a scribing width of 40–70μm.

[0039] During the P2 scribing process, a coaxial inert gas flow with a pressure of 0.2–0.5 MPa is applied simultaneously.

[0040] As a further improvement of the present invention, in step 3, the working conditions for drawing the line P3 are as follows:

[0041] A picosecond green laser with a wavelength of 532nm was selected, with a power of 0.5 to 1.0W, a scanning speed of 3000 to 6000 mm / s, a scribing width of 40 to 70 μm, and a pulse overlap of 30 to 40%.

[0042] As a further improvement of the present invention, a preprocessing step is included before performing step 1:

[0043] The glass substrate was subjected to a three-stage ultrasonic cleaning process using deionized water, ethanol, and isopropanol in sequence.

[0044] After drying at 70–90°C, ensure that the water contact angle on the glass substrate surface is less than or equal to 10 degrees.

[0045] As a further improvement of the present invention, in the preparation of the functional layer in step 2:

[0046] A PVD-NiOx hole transport layer with a thickness of 10–20 nm, a perovskite active layer with a thickness of 500–600 nm, and a C layer with a thickness of 20–30 nm were sequentially prepared. 60 Electron transport layer and atomic layer deposition: SnO2 electron transport layer with a thickness of 10-20 nm.

[0047] As a further improvement of the present invention, a P4 edge cleaning step is included after step 3:

[0048] Picosecond infrared lasers with a wavelength of 1064nm are used to clean the edge areas of the components, so that the total dead zone width is maintained within the range of 100-200μm.

[0049] The second objective of this invention is:

[0050] A laser marking system for implementing the method described above, comprising:

[0051] The laser generation module is used to generate the picosecond laser required for drawing lines P1, P2, and P3.

[0052] Optical execution module, including:

[0053] The P2 scribing unit is configured to use a picosecond laser to be incident from the back side of the substrate glass.

[0054] The P3 scribing unit is configured to use a picosecond laser to be incident from the metal electrode side from the front.

[0055] The visual positioning module is used to identify positioning marks and control the relative positions of the P1, P2, and P3 scribing units.

[0056] The control system is connected to each module and is used to control each scribing unit to work in sequence and to ensure that the scribing grooves of the first isolation groove, the second isolation groove, and the third isolation groove maintain partial overlap.

[0057] As a further improvement of the present invention, the laser generating module includes a 532nm picosecond green laser source and a 1064nm picosecond infrared laser source, as well as a laser selection switching device. The control system is configured to control the switching device to automatically select the corresponding laser source for the P1 scribing unit based on the received component area information.

[0058] The third objective of this invention:

[0059] A perovskite solar cell, the cell being fabricated by the laser scribing method described above.

[0060] By means of the above-described solution, the present invention has at least the following advantages:

[0061] 1. Resolved the core contradiction of the P1 process: By providing two options, picosecond green light and infrared laser, a flexible adaptation between "narrow dead zone" and "high reliability partitioning" is achieved to meet the needs of different application scenarios. The picosecond green light solution can achieve an extremely small dead zone of 10-20μm, improving the module fill factor; the infrared laser solution ensures complete partitioning between sub-cells, avoiding the "unbreakable" problem.

[0062] 2. High-quality scribing in the P2 process was achieved: A picosecond green laser with back-incidence was used, leveraging the difference in material absorption characteristics to achieve complete removal of the target layer at lower power while protecting the ITO layer from damage, significantly reducing the series resistance Rs. Compared with existing technologies, the back-incidence method reduces residue and improves scribing quality and consistency.

[0063] 3. Improved stability of the P3 process: Direct heating of the electrodes via front-side illumination allows for precise scribing that removes only the electrode layer without damaging the underlying functional layer, reducing the risk of material decomposition within the trenches. Simultaneously, it avoids the ductility tearing issue that can occur with back-side illumination, thus improving the long-term stability of the module.

[0064] 4. Significantly reduced total dead zone width: Through the synergistic optimization of three processes, the total dead zone width is controlled within the range of 100-200μm, which is significantly reduced compared to existing technologies, and is conducive to improving the geometric fill factor and photoelectric conversion efficiency of the module.

[0065] 5. High process compatibility and industrialization value: The picosecond green laser and infrared laser parameters used in this solution are within the range achievable by existing industrial-grade laser equipment, eliminating the need to develop entirely new equipment. Furthermore, the mark point positioning and visual compensation system ensure process stability and repeatability, making it promising for industrial applications.

[0066] 6. Reduced production costs: The P2 back-side incident solution reduces the requirements for laser power and reduces equipment energy consumption; precise control of each process reduces component scrap due to scribing quality issues and improves production yield.

[0067] 7. Improved module reliability: Through optimization measures such as avoiding ITO layer damage, reducing residues and preventing electrode tearing, the long-term operating stability of perovskite modules has been significantly improved, laying the foundation for their commercial application.

[0068] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, the following are preferred embodiments of the present invention described in detail with reference to the accompanying drawings. Attached Figure Description

[0069] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0070] Figure 1 This is a flowchart illustrating the fourth embodiment of the present invention;

[0071] Figure 2 This is a flowchart illustrating the process of marking lines P1 to P3 in the fourth embodiment of the present invention;

[0072] Figure 3 This is a diagram illustrating the line-drawing effect of using a picosecond green laser in the P1 line drawing in the fourth embodiment of the present invention.

[0073] Figure 4 This is a diagram illustrating the line-drawing effect of picosecond infrared laser used in the line drawing P1 in the fourth embodiment of the present invention.

[0074] Figure 5 This is a schematic cross-sectional view of the back-side incident line in the P2 scribe line of the fourth embodiment of the present invention;

[0075] Figure 6 This is a schematic diagram of back-side incidence in the P3 line of the fourth embodiment of the present invention;

[0076] Figure 7 This is a diagram illustrating the effect of back-side incident light in the P3 line drawing in the fourth embodiment of the present invention;

[0077] Figure 8 This is a schematic diagram of the frontal incidence in the P3 line in the fourth embodiment of the present invention;

[0078] Figure 9 This is a diagram showing the effect of frontal incidence in the P3 line drawing in the fourth embodiment of the present invention. Detailed Implementation

[0079] The specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples. The following examples are for illustrative purposes only and are not intended to limit the scope of the invention.

[0080] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0081] First embodiment of the present invention:

[0082] This embodiment of a laser scribing method for a perovskite solar cell includes the following steps:

[0083] Step 1, P1 scribing: A picosecond laser is used to perform the P1 scribing process on the transparent conductive layer to form the first isolation groove.

[0084] In step 1, the working conditions for marking P1 are dynamically selected based on the area of ​​the target battery:

[0085] When the area of ​​the target battery is less than 0.5m² 2 At that time, a picosecond green laser with a wavelength of 532nm was selected, with a power of 1.2 to 1.8W, a scanning speed of 1500 to 2500mm / s, and a scribing width of 10 to 20μm;

[0086] When the area of ​​the target battery is greater than or equal to 1.2m² 2 At that time, a picosecond infrared laser with a wavelength of 1064nm was selected, with a power of 1.8 to 2.4W, a scanning speed of 1000 to 2000mm / s, and pulse train mode was enabled, with a line width of 30 to 60μm.

[0087] P1 line drawing is a "dynamic decision-making" line drawing method based on physical characteristics and scene adaptation:

[0088] The specific technical contradiction to be resolved is that a single laser parameter cannot simultaneously satisfy the conflict between "the pursuit of extremely narrow dead zones in small-area components" and "the rigid requirement of high reliability (low conductivity) in large-area components." This is a long-standing practical problem in large-scale production.

[0089] For small areas: using 532nm green light, taking advantage of its high photon energy and moderate absorption by the transparent conductive layer (FTO / ITO), combined with the "cold processing" characteristics of picosecond laser, it is possible to achieve extremely narrow and clean grooves at the sub-20μm level under low thermal influence, directly achieving narrow dead zones.

[0090] For large areas: Switching to 1064nm infrared light, utilizing its higher glass transmittance and deeper effective processing tolerance, combined with the heat accumulation effect brought by the pulse train mode, can overcome the unevenness of large-area substrates and energy attenuation, ensuring 100% cut of the conductive layer over a stroke of tens of centimeters, achieving high reliability.

[0091] This step is not a simple "A or B" choice, but rather triggers two completely different laser processes based on the objective condition of component area. This reflects a non-obvious technological decision based on profound physical understanding and industrialization needs, and is itself innovative.

[0092] Step 2: P2 scribing: After the hole transport layer, perovskite active layer and electron transport layer are prepared in sequence, the P2 scribing process is performed. A picosecond laser is used to shine on the back side of the substrate glass to form a second isolation groove that exposes part of the transparent conductive layer.

[0093] In step 2, the working conditions for drawing the line on P2 are:

[0094] A picosecond green laser with a wavelength of 532nm was selected, with a power of 0.8–1.5W, a scanning speed of 2000–4000mm / s, and a scribing width of 40–70μm.

[0095] During the P2 scribing process, a coaxial inert gas flow with a pressure of 0.2–0.5 MPa is applied simultaneously.

[0096] The specific technical contradiction to be resolved: In the traditional P2 front-side incident process, there is an inherent contradiction between "the need to completely remove perovskite and other multi-layer thin films" and "the need to perfectly protect the fragile ITO conductive layer underneath".

[0097] This technique creatively utilizes the fundamental optical difference that ITO is a semi-transparent medium for 532nm lasers while the perovskite layer is a strong absorber for them. By incident from the back side of the glass, the laser penetrates the ITO layer with almost no loss before its energy is intensely absorbed and ablated by the perovskite layer. This is equivalent to achieving precise "through-the-mountain" processing in physics, fundamentally avoiding ITO damage.

[0098] Changing the laser incident direction from the conventional "front" to the "back" is based on a profound understanding of the optical properties of materials, providing a completely new and reverse technological approach to solving the industry's persistent problem of "underlying damage." This shift in thinking is not immediately obvious, but rather possesses outstanding substantive characteristics and significant progress.

[0099] Step 3: P3 scribing: After the metal electrode layer is prepared, the P3 scribing process is performed. A picosecond laser is used to shine on the metal electrode from the front to form the third isolation groove.

[0100] In step 3, the working conditions for drawing the line on P3 are:

[0101] A picosecond green laser with a wavelength of 532nm was selected, with a power of 0.5 to 1.0W, a scanning speed of 3000 to 6000 mm / s, a scribing width of 40 to 70 μm, and a pulse overlap of 30 to 40%.

[0102] The specific technical contradiction to be resolved: In P3 etching, there is a contradiction between "the need to completely remove the upper metal electrode" and "the need to prevent damage or decomposition of the lower metal oxide transport layer (such as SnO2)" and "avoiding the metal from tearing due to thermal stress".

[0103] This method utilizes the characteristics of Cu electrodes exhibiting extremely high surface absorption rates for 532nm laser light, while oxides such as SnO2 have low absorption rates and slow thermal diffusion at this wavelength. By incident the laser light from the electrode side from the front and employing a combination of low power (0.5-1.0W) and high speed (3000-6000mm / s), instantaneous vaporization and sublimation of the Cu electrode are achieved, while the heat transferred to SnO2 is far below its damage threshold. Simultaneously, the high scanning speed prevents lateral heat diffusion, thus preventing ductile tearing of the Cu.

[0104] This step is a typical "selective etching," but its innovation lies in the precise selection of a 532nm wavelength that matches the absorption characteristics of the Cu electrode, and the discovery of a specific parameter window that enables "sublimation etching" rather than "melting etching." This is not something that those skilled in the art can easily obtain through a limited number of experiments.

[0105] The first, second, and third isolation trenches overlap in the direction perpendicular to the substrate, with the total overlap area accounting for 20% to 30% of the area of ​​a single isolation trench, thus making the total dead zone width 100 to 200 μm.

[0106] A preprocessing step is included before step 1:

[0107] The glass substrate was subjected to a three-stage ultrasonic cleaning process using deionized water, ethanol, and isopropanol in sequence.

[0108] After drying at 70–90°C, ensure that the water contact angle on the glass substrate surface is less than or equal to 10 degrees.

[0109] In the preparation of the functional layer in step 2:

[0110] A PVD-NiOx hole transport layer with a thickness of 10–20 nm, a perovskite active layer with a thickness of 500–600 nm, a C60 electron transport layer with a thickness of 20–30 nm by vapor deposition, and a SnO2 electron transport layer with a thickness of 10–20 nm by atomic layer deposition were prepared sequentially.

[0111] Step 3 is followed by the P4 edge cleaning step:

[0112] Picosecond infrared lasers with a wavelength of 1064nm are used to clean the edge areas of the components, so that the total dead zone width is maintained within the range of 100-200μm.

[0113] A brief description of the synergistic effect between the above steps:

[0114] 1. Functional complementarity and synergy:

[0115] The core function of P2 (back-incidence) is to "protect the front electrode (ITO)".

[0116] The core function of P3 (front-facing incident) is to "protect the bottom functional layer (SnO2)".

[0117] Synergistic effect: These two steps address the most critical interface damage issues from the "bottom" and "top" of the device, respectively, forming a perfect "protective closed loop." If only one is used, the other interface will inevitably be damaged, and the overall performance cannot reach its optimal level. This combination of "back and front" incident directions constitutes an innovative process architecture that is inherently self-consistent and functionally complementary.

[0118] 2. Process-dependent collaboration:

[0119] P1 (high-quality narrow scribing) is the foundation of "cooperative positioning". Only when P1 scribing a clean and controllable width groove can the subsequent P2 and P3 use it as a reference to achieve a precise overlap of 20-30%.

[0120] Synergistic effect: Step P1 provides a precise "spatial coordinate reference" for the entire synergistic system. Together, these three elements constitute a sequential process chain of "reference-protection-re-protection," with the former being the prerequisite and guarantee for the latter. This strict sequential dependency and precision transferability reflects its essence as an inseparable whole technical solution.

[0121] 3. Emergent synergy:

[0122] The ultimate effect of this invention, namely an ultra-narrow dead zone, is the result of the combined effect of P1 (narrow scribbled line), P2 / P3 (precise overlap), and cooperative positioning. The achievement of this overall effect demonstrates the non-obviousness of its technical solution.

[0123] The second embodiment of the present invention:

[0124] This embodiment provides a laser marking system for implementing the method described above, comprising:

[0125] The laser generation module is used to generate the picosecond laser required for drawing lines P1, P2, and P3.

[0126] Optical execution module, including:

[0127] The P2 scribing unit is configured to use a picosecond laser to be incident from the back side of the substrate glass.

[0128] The P3 scribing unit is configured to use a picosecond laser to be incident from the metal electrode side from the front.

[0129] The visual positioning module is used to identify positioning marks and control the relative positions of the P1, P2, and P3 scribing units.

[0130] The control system is connected to each module and is used to control each scribing unit to work in sequence and to ensure that the scribing grooves of the first isolation groove, the second isolation groove, and the third isolation groove maintain partial overlap.

[0131] The laser generation module includes a 532nm picosecond green laser source and a 1064nm picosecond infrared laser source, as well as a laser selection switching device. The control system is configured to control the switching device to automatically select the corresponding laser source for the P1 scribing unit based on the received component area information.

[0132] The third embodiment of the present invention:

[0133] This embodiment describes a perovskite solar cell, which is fabricated using the laser scribing method described above.

[0134] Fourth embodiment of the present invention:

[0135] like Figures 1-2 As shown, the laser scribing process in this embodiment includes the following steps:

[0136] 1. Perform the P1 scribing process on the transparent conductive layer;

[0137] 2. After sequentially preparing the electron transport layer, perovskite active layer, and hole transport layer, perform the P2 scribing process;

[0138] 3. After preparing the metal electrode layer, perform the P3 scribing process;

[0139] Among them, the three processes of scribing P1, P2, and P3 use different laser parameters and incident methods.

[0140] The specific process steps are as follows:

[0141] Pre-treatment process:

[0142] FTO substrate cleaning: Three-stage ultrasonic cleaning (deionized water → ethanol → isopropanol), drying at 80℃, ensuring water contact angle ≤10 degrees (to avoid focal length deviation).

[0143] P1 is marked (transparent conductive layer division), such as Figures 3-4 As shown.

[0144] Narrow dead zone mode (<0.5m) 2 Components):

[0145] 532nm picosecond green light (IPG YLP-10), power 1.2~1.8W, speed 1500~2500mm / s, scribing width 10~20μm; with dynamic energy compensation, conductivity <2%.

[0146] High reliability mode (≥1.2m) 2 Components):

[0147] 1064nm picosecond infrared (Raycus RFL-P10), power 1.8~2.4W, speed 1000~2000mm / s, scribing width 30~60μm; pulse train mode reduces glass cracking, conductivity <1%.

[0148] Functional layer fabrication:

[0149] PVD-NiOx (10-20nm) → PVK layer (500-600nm, slot coating / inkjet printing) → C vapor deposition 60 (20-30nm) → ALD-SnO2 (10-20nm, thinner insulating layer than existing technology 4 without additional cost).

[0150] The dual-laser selection scheme for the P1 process: picosecond green light (532nm) or infrared light (1064nm) laser is selected for P1 scribing according to application requirements. The picosecond green light achieves a narrow dead zone of 10-20μm, while the infrared light ensures complete division of the sub-cells, which solves the contradiction that a single laser cannot achieve both in the existing technology.

[0151] P2 scribing (active layer interconnection), such as Figures 5-7 As shown.

[0152] 532nm picosecond green light back-incidence (glass side), power 0.8-1.5W, speed 2000-4000mm / s, scribing width 40-70μm; coaxial airflow to remove residues (percentage <3%), ITO damage rate <5%.

[0153] Back-side incident optimization of the P2 process: Picosecond green light (532nm) is used for P2 scribing from the back side. By taking advantage of the difference in absorption of green light between ITO and perovskite, the target layer can be completely removed at low power, protecting the ITO layer from damage and reducing residues.

[0154] P3 marking (back electrode segmentation), such as Figures 8-9 As shown.

[0155] 532nm picosecond green light is incident from the front (Cu electrode side), with a power of 0.5-1.0W, a speed of 3000-6000mm / s, and a pulse overlap of 30-40%. Selective etching is achieved by utilizing the difference in material absorption, with SnO2 decomposition rate <5% and Cu tearing rate <1%.

[0156] The precise scribing mechanism of the P3 process: Picosecond green light (532nm) is used for P3 scribing from the front, which removes only the electrode layer without damaging the underlying functional layer, avoiding the problem of metal electrode ductility tearing and reducing the risk of material decomposition in the trench.

[0157] P4 edge clearing and dead zone coordination:

[0158] 1064nm infrared laser edge clearing (edge ​​1.2-1.5mm); 20-30% overlap of the grooves in P1-P3, total dead zone 100-200μm (no additional cost).

[0159] The three-process collaborative optimization strategy: By matching and controlling the parameters of each process (P1, P2, P3), the total dead zone width is controlled within the range of 100-200μm, which significantly improves the performance of the components.

[0160] Specific ranges of laser parameters: specific combinations of laser power, scanning speed, and repetition frequency in each process, such as 1.2-1.8W power and 1500-2500mm / s speed for P1 picosecond green light, and 0.8-1.5W power for P2 back-incident laser, etc.

[0161] Incident direction selection based on material properties: Based on the differences in the absorption characteristics of different layers of materials to laser, the front or back incident method is selected to selectively remove the target layer while protecting the underlying material.

[0162] Application of positioning and compensation system: Combining mark point marking and visual compensation technology, the relative positional accuracy of the three scribing lines P1, P2, and P3 is ensured, so that the distance between the grooves is controlled within 50μm.

[0163] Method for controlling the total dead zone width: A total dead zone width of 100-200μm can be achieved by optimizing the combination of scribing widths for each process (P1: 10-60μm, P2: 40-70μm, P3: 40-70μm).

[0164] First experimental example of the present invention:

[0165] Laser scribing process with high fill factor orientation

[0166] This experimental example focuses on the production of perovskite modules that require a high fill factor, and uses the following specific process parameters:

[0167] Result: Only the metal electrode layer was removed; the underlying SnO2 layer remained intact without any tearing.

[0168] Overall results: The total dead zone width of the three processes is 115μm, the component fill factor is increased to over 85%, and the series resistance Rs is controlled within 10Ω.

[0169] Second experimental example of the present invention:

[0170] High-reliability orientation laser scribing process

[0171] This experimental example focuses on the production of high-reliability oriented perovskite modules, using the following specific process parameters:

[0172]

[0173] Overall results: The total dead zone width of the three processes is 160μm. The module performed stably in temperature cycling tests from -40℃ to 85℃ with no significant efficiency degradation.

[0174] The present invention addresses the following specific technical problems through the above-described technical solution:

[0175] We offer a "dual laser selection on demand" solution for the P1 process, enabling small-area modules (<0.5m²). 2 Narrow dead zone (10-20μm, conductivity <2%), large area module (≥1.2m) 2 High reliability (conductivity <1%, dead zone 30-60μm), overcoming the compatibility defects of existing technologies 1 and 2 with single lasers;

[0176] The P2 process, "backward incidence + material absorption difference", is optimized to reduce the ITO damage rate to <5% and the residual area ratio to <3%, replacing the high-damage front-incidence schemes of existing technologies 2 and 3.

[0177] The P3 process is improved by "front-side incident selective etching", which removes only the Cu electrode, with SnO2 decomposition rate <5% and electrode tearing rate <1%, thus solving the stability problem that is not covered by existing technologies 3 and 4.

[0178] By coordinating the entire process of "laser type - incident direction - etched groove overlap", the total dead zone is controlled within 100-200μm, forming a solution of "pre-optimization instead of post-repair / packaging", which improves the mass production yield to ≥95% and avoids the additional costs of existing technologies 1 and 4.

[0179] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implying the number of indicated technical features. Thus, a feature defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0180] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art will understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0181] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A laser scribing method for perovskite solar cells, characterized in that, Includes the following steps: Step 1, P1 scribing: A picosecond laser is used to perform the P1 scribing process on the transparent conductive layer to form the first isolation groove; Step 2: P2 scribing: After the hole transport layer, perovskite active layer and electron transport layer are prepared in sequence, the P2 scribing process is performed. A picosecond laser is used to shine on the back side of the substrate glass to form a second isolation groove that exposes part of the transparent conductive layer. Step 3: P3 scribing: After the metal electrode layer is prepared, the P3 scribing process is performed. A picosecond laser is used to shine on the metal electrode from the front to form the third isolation groove. The first, second, and third isolation trenches overlap in the direction perpendicular to the substrate, with the total overlap area accounting for 20% to 30% of the area of ​​a single isolation trench, thereby making the total dead zone width 100 to 200 μm.

2. The laser scribing method for a perovskite solar cell as described in claim 1, characterized in that, In step 1, the working conditions for marking P1 are dynamically selected based on the area of ​​the target battery: When the area of ​​the target battery is less than 0.5m² 2 At that time, a picosecond green laser with a wavelength of 532nm was selected, with a power of 1.2 to 1.8W, a scanning speed of 1500 to 2500mm / s, and a scribing width of 10 to 20μm; When the area of ​​the target battery is greater than or equal to 1.2m² 2 At that time, a picosecond infrared laser with a wavelength of 1064nm was selected, with a power of 1.8 to 2.4W, a scanning speed of 1000 to 2000mm / s, and pulse train mode was enabled, with a line width of 30 to 60μm.

3. The laser scribing method for a perovskite solar cell as described in claim 1, characterized in that, In step 2, the working conditions for drawing the line P2 are: A picosecond green laser with a wavelength of 532nm was selected, with a power of 0.8–1.5W, a scanning speed of 2000–4000mm / s, and a scribing width of 40–70μm. During the P2 scribing process, a coaxial inert gas flow with a pressure of 0.2–0.5 MPa is applied simultaneously.

4. The laser scribing method for a perovskite solar cell as described in claim 1, characterized in that, In step 3, the working conditions for drawing the line P3 are: A picosecond green laser with a wavelength of 532nm was selected, with a power of 0.5 to 1.0W, a scanning speed of 3000 to 6000 mm / s, a scribing width of 40 to 70 μm, and a pulse overlap of 30 to 40%.

5. The laser scribing method for a perovskite solar cell as described in claim 1, characterized in that, A preprocessing step is also included before performing step 1: The glass substrate was subjected to a three-stage ultrasonic cleaning process using deionized water, ethanol, and isopropanol in sequence. After drying at 70–90°C, ensure that the water contact angle on the glass substrate surface is less than or equal to 10 degrees.

6. The laser scribing method for a perovskite solar cell as described in claim 1, characterized in that, In the preparation of the functional layer in step 2: A PVD-NiOx hole transport layer with a thickness of 10–20 nm, a perovskite active layer with a thickness of 500–600 nm, and a C layer with a thickness of 20–30 nm were sequentially prepared. 60 Electron transport layer and atomic layer deposition: SnO2 electron transport layer with a thickness of 10-20 nm.

7. The laser scribing method for a perovskite solar cell as described in claim 1, characterized in that, Following step 3, a P4 edge-cleaning step is also included: Picosecond infrared lasers with a wavelength of 1064nm are used to clean the edge areas of the components, so that the total dead zone width is maintained within the range of 100-200μm.

8. A laser scribing system for implementing the method as described in any one of claims 1 to 7, characterized in that, include: The laser generation module is used to generate the picosecond laser required for drawing lines P1, P2, and P3. Optical execution module, including: The P2 scribing unit is configured to use a picosecond laser to be incident from the back side of the substrate glass. The P3 scribing unit is configured to use a picosecond laser to be incident from the metal electrode side from the front. The visual positioning module is used to identify positioning marks and control the relative positions of the P1, P2, and P3 scribing units. The control system is connected to each module and is used to control each scribing unit to work in sequence and ensure that the scribing grooves of the first isolation groove, the second isolation groove, and the third isolation groove maintain partial overlap.

9. The laser marking system as described in claim 8, characterized in that, The laser generating module includes a 532nm picosecond green laser source and a 1064nm picosecond infrared laser source, as well as a laser selection switching device. The control system is configured to control the switching device to automatically select the corresponding laser source for the P1 scribing unit based on the received component area information.

10. A perovskite solar cell, characterized in that, The battery is prepared by the laser scribing method as described in any one of claims 1 to 7.

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