Perovskite solar cell laser scribing device

Abstract

The invention belongs to the technical field of perovskite solar cell processing, and particularly relates to a perovskite solar cell laser scribing device, which comprises a perovskite solar cell body, a laser and a focusing system, and is characterized in that the laser emits a laser beam, and the focusing system focuses the laser beam to a scribing area of the perovskite solar cell body; particularly, the perovskite solar cell further comprises a current-conducting plate which is located on the back face of the perovskite solar cell body and connected with the ground. The conductive plate is connected with the ground to form a low-resistance path, so that photo-generated charges, plasma induced charges or heat shock charges generated in a laser irradiation process are effectively discharged, and the charges are prevented from being accumulated on a perovskite layer or an interface. The current-conducting plate is compact in structure and easy to integrate in an existing laser scribing platform, the perovskite cell layer structure does not need to be changed, and the current-conducting plate is convenient to popularize and apply to the laser manufacturing process of various perovskite solar cell modules.

Description

Technical Field

[0001] The present invention belongs to the technical field of perovskite solar cell processing, and particularly relates to a laser scribing device for perovskite solar cells. Background Art

[0002] Laser scribing of perovskite solar cells is used to modularize perovskite solar cells, that is, to divide the entire perovskite solar cell into multiple small cell units (referred to as "self-cells" or "strips"), and then through series connection to increase the output voltage and module efficiency.

[0003] The laser scribing process is generally divided into three steps, namely P1, P2, and P3 scribing. P1 scribing is to remove the transparent conductive oxide and electrically isolate the bottom electrode. P2 scribing is to remove the perovskite layer and the electron transport layer to connect adjacent units in series through the bottom electrode. P3 scribing is to cut the metal top electrode to prevent short-circuiting of the top electrodes of different units. Among them, the P2 scribing has the highest technical difficulty, mainly due to the poor thermal stability of the perovskite layer material and the complex interface charges.

[0004] In P2 scribing, when irradiated by laser, the perovskite lattice is excited to generate a large number of photo-generated electron-hole pairs, resulting in local charge accumulation. In addition, the perovskite layer material and the electron transport layer material have different conductivities and bandgap structures, which will also form a potential difference or charge trap at the interface. Eventually, these charges form a strong electric field in the local area, leading to abnormal carrier migration, electric field distortion, perovskite lattice stress accumulation and even structural damage; at the same time, it also leads to interfacial chemical reactions, promotes metal ion migration, and causes electrode corrosion or perovskite decomposition. Therefore, charge accumulation seriously threatens the battery performance and long-term stability.

[0005] Existing research mainly optimizes the laser scribing parameters to improve the module performance and large-scale feasibility, such as the reference (Laser-Scribing Optimization for Sprayed SnO2-Based Perovskite SolarModules on Flexible Plastic Substrates, ACS Applied Energy Materials, Vol. 4,4507-4518, 2021). Although such research has achieved certain efficiency improvements, it still has not fundamentally solved the core problems faced by laser scribing, including interface instability caused by charge accumulation. These literatures lack in-depth discussion on the physical and chemical interaction mechanism between the laser and the material interface, and are not breakthroughs at the mechanism level. There are still limitations in popularization and sustainability in the face of more complex material systems or application scenarios with higher stability requirements. Summary of the Invention

[0006] To solve the above problems, the present invention provides a laser scribing device for perovskite solar cells, comprising a perovskite solar cell body, a laser, and a focusing system. The laser emits a laser beam, and the focusing system focuses the laser beam onto the scribing area of the perovskite solar cell body; In particular, the present invention further includes a conductive plate located on the back of the perovskite solar cell body, and the conductive plate is connected to the ground.

[0007] In the present invention, by providing a grounded conductive plate on the back of the perovskite solar cell body, a low-impedance charge discharge path is formed during the laser scribing process, effectively guiding the photo-generated charges, thermally excited charges, or plasma-induced charges generated by laser excitation to quickly conduct to the ground, thereby preventing charge accumulation inside the device or at the interface. Charge accumulation can lead to problems such as local electric field distortion, enhanced charge recombination, interfacial ion migration, and lattice instability, which in turn affect the depth control of laser scribing, the integrity of the scribing boundary, and the consistency of electrical connection. Through the discharge mechanism of the conductive plate in the present invention, these adverse effects are suppressed, and the scribing accuracy, uniformity, and overall device stability are improved.

[0008] The material of the conductive plate is metal. Metal has excellent electrical conductivity and can provide a low-resistance charge conduction path, which can more efficiently guide and discharge the transient charges generated in the perovskite battery during the laser scribing process, significantly reducing the risk of charge accumulation. In addition, the metal conductive plate also has good thermal conductivity, which can quickly dissipate local heat during the laser processing, reduce thermal stress concentration, and prevent uneven material ablation or structural deformation caused by temperature rise. The conductive plate contacts the bottom electrode side of the perovskite solar cell body. The bottom electrode of the perovskite battery is usually a transparent conductive layer (such as ITO or FTO). Directly connecting to this electrode can establish a complete and low-resistance electrical circuit, enabling the photo-generated charges or induced charges generated in the battery structure during the laser irradiation to quickly conduct to the ground through the conductive plate, avoiding charge accumulation in the active layer or at the interface. In addition, contacting the bottom electrode can also enhance the electric field stability, prevent charge back-migration or form a potential barrier in the perovskite layer, thereby reducing problems such as ion migration, thermal stress, and material decomposition in the scribing area. The conductive plate and the perovskite solar cell body are electrically connected through a conductive bonding material or a pressing structure.

[0009] Furthermore, the conductive plate and the perovskite solar cell body can be electrically connected through a conductive bonding material, which includes conductive silver paste, carbon paste, metal nano-paste, or other low-temperature curable conductive composites. In practical applications, the material can be evenly coated on the contact area between the conductive plate and the bottom electrode, and a continuous conductive interface can be formed through pressing or natural fitting, and cured at room temperature or low temperature. This method has good interface adhesion and stability, low resistance, and is not easy to loosen, and is suitable for long-term fixed connection of large-area devices. At the same time, the bonding material has certain flexibility and buffering performance, can effectively absorb the thermal stress during the laser processing, adapt to the flexible battery structure, and ensure the reliability of the electrical connection and the stability of the processing process. The conductive plate can also be electrically connected to the bottom electrode of the perovskite solar cell body through a pressing structure. The pressing structure can adopt a spring-loaded device, a bolt clamp, a magnetic adsorption connector, or a conductive elastic cushion layer (such as conductive foam) is set for mechanical pressing. This method does not require a bonding material, avoiding the potential impact of solvent volatiles or chemical residues on the perovskite layer, and is particularly suitable for perovskite devices that are sensitive to humidity or chemicals. At the same time, the connection method of the pressing structure is convenient for disassembly and maintenance, and is suitable for the rapid deployment of experimental platforms, replaceable fixtures, or temporary grounding occasions in laser scribing equipment. In addition, mechanical crimping can ensure uniform pressure and large-area contact, further improving the charge discharge efficiency and the electric field balance of the processing area.

[0010] Furthermore, the conductive plate is connected to an adjustable DC bias power supply, which is used to apply a negative bias voltage to the conductive plate during the laser scribing process. On the basis of discharging charges, the electric field distribution is further actively regulated to improve the stability and accuracy of laser scribing. By applying a negative bias voltage, an electric field in the direction of the conductive plate is established in the perovskite solar cell body, which helps to guide the photo-generated electrons or plasma-induced charges generated in the laser action area to quickly migrate to the conductive plate, thereby more effectively preventing the charges from staying and accumulating at the active layer or interface, and reducing the risk of electric field distortion and interface breakdown. At the same time, the negative bias voltage can also inhibit ion migration and material decomposition, which helps to control the range of the heat-affected zone and reduce the scribing edge damage, and is particularly suitable for perovskite structures that are sensitive to laser energy, thereby improving the scribing uniformity and device yield.

[0011] Furthermore, a high-frequency thermal oscillation conductive layer is provided inside or on the surface of the conductive plate. A micro-thermal oscillation device is embedded in the conductive plate, and by applying a high-frequency heat flow (such as at the 10 kHz level), a micro-thermal disturbance coordinated with the laser pulse frequency is formed to promote heat diffusion and interrupt the concentrated path of the thermal gradient.

[0012] Furthermore, a metal protrusion structure is provided on one side of the conductive plate close to the laser irradiation area, which helps to enhance the local electric field strength and charge collection ability, thereby further improving the charge discharge efficiency. The metal protrusion structure can form an electric potential gradient around the laser irradiation area, making the charges generated by laser excitation more likely to migrate concentratedly along the electric field direction to the conductive plate, reducing the accumulation of charges at the perovskite layer or interface. At the same time, the metal protrusion can also act as a micro heat dissipation fin, enhancing local heat conduction, reducing the accumulation of thermal stress during the laser processing, and avoiding microcracks or uneven ablation of the material due to overheating.

[0013] Furthermore, a high-frequency thermal oscillation conductive layer is provided inside or on the surface of the conductive plate. A group of structures with stepped grooves (micro plasma traps) are micro-nano processed on the surface of the protrusion structure of the conductive plate to capture the plasma flow and charged particles generated during the laser scribing process, reducing their secondary excitation and ablation effect on the surrounding materials.

[0014] Furthermore, the protrusion structure is placed on the lower side of the laser irradiation area to achieve precise alignment control of the electric field and thermal field, thereby maximizing the processing quality and stability of the laser scribing area. This position layout makes the protrusion structure directly face the laser action point. At the moment when the laser generates charges, the protrusion can guide the charges to the conductive plate along the shortest path, improving the local charge discharge rate and avoiding the accumulation of charges near the laser ablation area. In addition, the protrusion structure is close to the heat source center, which can enhance the vertical heat dissipation ability, slow down the heat diffusion to the surrounding sensitive structures, and reduce the size of the heat affected zone and the risk of thermal stress concentration.

[0015] Furthermore, the width of the protrusion structure is greater than the laser scribing width, ensuring that during the laser irradiation process, no matter what slight deviation is caused by thermal drift, equipment error or spot expansion, the laser is always within the effective action range of the protrusion structure, so as to continuously play the synergistic function of charge guiding and heat conduction.

[0016] Furthermore, the conductive plate is connected to an ultrasonic generating device, which generates ultrasonic waves. The ultrasonic waves induce micro-vibrations and a periodic stress field in the perovskite solar cell body, which helps to break the charge bound state in the laser irradiation area, promote the rapid migration and release of charges to the conductive plate, and significantly inhibit the interface electric field distortion and recombination loss caused by charge accumulation. At the same time, the ultrasonic vibration can also reduce the instantaneous ablation threshold of the material, making it easier for the laser to achieve fine peeling, reducing the thermal damage to the bottom electrode or substrate during the scribing process. In addition, the ultrasonic action can also improve the gas exchange and debris discharge in the laser action area, avoid the accumulation of ablation residues, keep the scribing interface clean and flat, thereby improving the scribing accuracy, boundary integrity and electrical consistency of subsequent series connection.

[0017] Furthermore, ultrasonic waves are propagated along the laser scribing direction, forming a periodic mechanical disturbance and stress field distribution consistent with the scribing direction on the laser processing path, thereby achieving a synergistic enhancement effect of the interaction between ultrasound and laser. The ultrasonic waves along the scribing direction help to accelerate the directional migration and release of charges in the laser-excited region, reduce the lateral diffusion and accumulation of charges on the scribing track, and improve the charge discharge efficiency and electric field uniformity. At the same time, this direction consistency can also induce a stress relaxation effect along the line in the material microstructure, which is beneficial to controlling the crack propagation direction and weakening the local thermal stress, and reducing the risk of edge burrs and structural tearing caused by laser thermal shock.

[0018] It should be noted that in the present invention, ultrasonic energy preferentially propagates along the convex structures on the conductive plate. The convex structures are in direct contact with the bottom electrode of the perovskite solar cell body and have good mechanical coupling properties, which are the main channels for ultrasonic waves to be transmitted into the device. At the same time, the convex structures are small in size and concentrated in mass, and the acoustic impedance is more matched with the laser processing area, so that the ultrasonic waves are more likely to focus and locally enhance the acoustic wave energy at the convex points when propagating on the conductive plate. Compared with the planar area of the conductive plate, the convex structures can support local high-frequency vibration modes, significantly improving the micro-amplitude perturbation efficiency in the laser irradiation area. By concentrating and guiding the ultrasonic energy to the laser scribing area, the charge perturbation and release can be enhanced, the stress concentration in the laser heat-affected zone can be reduced, the scribing quality can be further improved, the material damage can be reduced, and the process stability can be improved, which is particularly suitable for the perovskite battery structure that is sensitive to heat and electricity.

[0019] Advantages of the present invention: (1) In the present invention, the conductive plate is connected to the ground to form a low-resistance path, effectively discharging the photo-generated charges, plasma-induced charges or thermally excited charges generated during the laser irradiation process, and preventing the charges from accumulating in the perovskite layer or at the interface.

[0020] (2) Since charge accumulation is often accompanied by local heat accumulation, the grounding and discharging effect of the conductive plate indirectly alleviates the heat concentration and reduces the material ablation, discoloration or structural damage caused by the temperature rise.

[0021] (3) The conductive plate has a compact structure and is easy to be integrated into the existing laser scribing platform without changing the perovskite battery layer structure, which is convenient for popularizing and applying to the laser manufacturing process of various perovskite solar cell modules.

[0022] Based on the above beneficial effects, the present invention has a good application prospect in the field of perovskite solar cell processing technology. Description of the Drawings

[0023] Figure 1 It is a schematic diagram of a laser scribing device for a perovskite solar cell.

[0024] Figure 2Schematic diagram of another laser scribing device for perovskite solar cells.

[0025] In the figure: 1, perovskite solar cell body; 2, laser; 3, focusing system; 4, conductive plate; 41, convex structure. Specific implementation manners

[0026] To make the objectives, technical solutions and advantages of the present application clearer and more understandable, the following examples are given with reference to the accompanying drawings to further elaborate on the present application in detail.

[0027] Example 1 This example provides a laser scribing device for perovskite solar cells, as Figure 1 shown, including a perovskite solar cell body 1, a laser 2, a focusing system 3 and a conductive plate 4. The perovskite solar cell body 1 has a flexible p-i-n structure, is prepared on a PET substrate, and the bottom electrode is an ITO layer with a thickness of about 150 nm; the laser 2 uses a pulsed ultraviolet laser with a wavelength of 355 nm, a pulse width of 10 ns, and a working power of 40 mW to 60 mW. Combined with the focusing system 3, the laser beam is focused to a spot within 25 μm, and P2 scribing processing is performed on the surface of the perovskite solar cell body 1. The focusing system 3 is a two-axis galvanometer scanning system, and the scribing speed is about 80 mm / s. The conductive plate 4 is made of a copper plate with a thickness of 1 mm and dimensions of 100 mm × 150 mm, is arranged on the back of the perovskite solar cell body 1, contacts one side of the bottom electrode, and forms a low-resistance electrical connection through silver glue bonding, and is grounded at the same time to discharge the charges generated during the laser scribing process.

[0028] Preferably, in order to further improve the charge guiding efficiency and laser processing stability, the conductive plate 4 can be arranged in a double-layer structure. The upper layer is a high-conductivity metal layer (such as copper, silver or gold-plated copper), which directly contacts the bottom electrode of the perovskite solar cell body to provide an efficient charge discharge channel; the lower layer is a high-thermal conductivity or elastic support layer (such as a graphite heat sink, an aluminum alloy plate or an elastic metal plate with a microporous structure), which is used to enhance the heat diffusion ability, absorb the thermal shock during laser processing, and provide a stable support platform for the flexible device. The two layers can be connected by a conductive adhesive or threaded compression to ensure good electrical and thermal coupling. The double-layer structure can also achieve functional division of labor: the upper layer focuses on electrical contact and electric field regulation, and the lower layer strengthens thermal management and mechanical stability, so as to achieve more precise charge control, more uniform thermal field distribution and smaller scribing stress area, which helps to further improve the scribing quality and device yield, and is particularly suitable for the batch processing scenario of large-area flexible perovskite solar cell modules.

[0029] Example 2 Based on Example 1, a set of adjustable DC bias voltage power supply system is connected to the conductive plate 4, which is used to actively apply a negative bias voltage during the laser scribing process to guide the directional release of charges, thereby suppressing the accumulation of charges in the laser irradiation area. The conductive plate is still made of high-purity copper plate with a thickness of 1 mm and a size of 100 mm × 150 mm, and is in contact with the bottom electrode of the perovskite solar cell body 1 by silver glue or spring pressing method, and maintains good electrical connection. The conductive plate is connected to an adjustable DC regulated power supply through a shielded wire, with the ability to continuously adjust within the range of ±6 V and a voltage accuracy of ±0.01V.

[0030] Before laser scribing, first set the power supply output to –1.5 V (relative to the electrode potential of the perovskite solar cell body 1) and apply it to the conductive plate 4, so that it is in a negative potential state relative to the laser irradiation area. This bias voltage effectively promotes the migration of free electrons and thermally induced charges generated by laser excitation towards the conductive plate 4 by enhancing the electric field gradient, accelerating the charge release rate, and preventing them from accumulating at the functional layer or interface. At the same time, this electric field regulation can also inhibit the ion migration in the laser action area and reduce the thermal damage and electrochemical instability of the material.

[0031] Furthermore, the bias voltage power supply connected to the conductive plate 4 is a pulsed bias voltage source, and its output is a periodically modulated negative voltage signal with a frequency range of 1–100 kHz and a duty cycle of 10%–90%, and is synchronized or phase-coupled with the laser pulse frequency. The pulsed bias voltage provides an enhanced electric field intensity during the laser action, inducing the rapid release of photo-generated charges or plasma-induced charges towards the conductive plate, thereby reducing the charge retention, interface polarization and recombination loss at the active layer or interface; while during the laser pulse interval, by reducing or removing the bias voltage, the interface thermal accumulation and electrochemical stress are alleviated, and the risk of material ion migration is reduced. Through the coordinated regulation of the pulsed bias voltage and the laser pulse, a dynamic electric field regulation mechanism can be constructed in the time domain, improving the charge guiding efficiency, optimizing the thermal-electric field distribution, enhancing the scribing edge clarity, material integrity and device electrical consistency, and is suitable for the high-precision scribing processing of flexible perovskite devices or temperature-sensitive interface structures.

[0032] Example 3 Based on Example 1 and Example 2, as Figure 2 shown, a metal protrusion structure 41 is arranged on the side of the conductive plate 4 close to the laser irradiation area to further improve the charge discharge efficiency and scribing quality control ability.

[0033] Specifically, on the conductive plate, a plurality of metal protrusion structures 41 are arranged on the lower side close to the laser irradiation area. Each protrusion structure is a copper strip structure integrally processed with the conductive plate and prepared by precision milling. Each protrusion strip has a rectangular cross-section, with a width of 80 μm (slightly larger than the laser scribing width of 25 μm - 30 μm to ensure coverage even with alignment errors), a length of 5 mm (extending along the scribing direction), a height of 200 μm (the part protruding above the conductive plate plane to enhance local contact), and an inter-strip spacing of 500 μm, forming a uniform layout.

[0034] The protrusion structure 41 is directly placed below the laser irradiation path, that is, there is a corresponding protrusion directly below each scribing trajectory. It makes line contact or surface contact with the bottom electrode of the perovskite cell, and ensures a stable electrical connection through the conductive silver paste dot bonding method.

[0035] In this embodiment, the local electric field is enhanced through the protrusion structure 41, the charge collection ability in the laser excitation area is improved, charge accumulation is reduced, and the charge release rate is increased; in addition, the metal protrusion can serve as a micro thermal channel to enhance the longitudinal heat conduction of the laser heat, reduce the lateral heat diffusion, and reduce the thermal influence area. In addition, the protrusion edge has a certain scattering guiding effect, which helps to reduce the interference of excess scattered light on the surrounding area.

[0036] Preferably, a plurality of parallel arranged metal protrusion structures 41 are only provided in the area of the P2 scribing trajectory corresponding to the perovskite solar cell body 1. If the protrusion structures 41 are uniformly distributed on the whole plate, it will cause additional indentation, mechanical stress or installation error risks to the flexible perovskite solar cell. Locally setting the protrusion structure 41 can avoid unnecessary interference in the non-processing area and ensure the integrity of the overall structure of the cell.

[0037] Preferably, the protrusion structure 41 has a serrated profile, and its tooth tips are arranged along the laser scribing direction. The tooth pitch of a single serration is 50 - 100 μm, the tooth height is 100 - 200 μm, and the tooth angle is 60 - 90°. The serrated surface is formed by precision etching or mechanical processing and contacts the bottom electrode of the perovskite solar cell body. Compared with the straight protrusion structure, the serrated structure can form a periodic electric field gradient at the microscale during the laser scribing process, effectively enhancing the charge collection ability in the laser excitation area, promoting the rapid release of photo-generated electrons along the direction pointed by the serrations to the conductive plate 4, and reducing the risk of charge accumulation at the scribing edge.

[0038] Furthermore, a local plasma trap structure is provided on the surface of the conductive plate 4, which is used to capture high-energy plasma and charged particles generated during the laser scribing process, improve the thermal field and electric field stability in the scribing area, and enhance the scribing edge quality. Specifically, the plasma trap structure is a micro-nano groove array disposed on the convex structure 41, specifically including: a plurality of "inverted cone" micro-grooves or "V-shaped" groove arrays extending along the laser scribing direction, with their openings facing the laser incident side, the groove depth being 10–50 microns, the groove width being 5–20 microns, and the groove pitch being 50–200 microns. The above grooves can be directly processed on the surface of the metal conductive plate by laser etching, plasma dry etching or micro-milling processes. This structure deflects the plasma flow trajectory through the spatial configuration, causing some high-energy particles to fall into the grooves, where they are passively retained or scattered to reduce energy, thereby preventing them from directly hitting the perovskite layer or the electrode interface and slowing down the secondary impact on the material structure. At the same time, the inverted cone structure can also form a relatively high surface potential well at the bottom of the groove, and induce the convergence of charged particles by using the charge attraction mechanism, further enhancing the trapping effect. Preferably, the plasma trap structure is disposed on both sides of the convex structure 41 close to the laser irradiation point, forming a symmetrically distributed trap band on the left and right, with its length direction parallel to the laser scanning trajectory and its width direction covering the scribing error area, so as to ensure that the buffering effect can be exerted under the conditions of laser deviation or multiple scans. Furthermore, the surface of the conductive plate can be blackened or coated with a high-resistance ceramic micro-layer, on the one hand, enhancing the energy dissipation of the plasma in the trap structure, and on the other hand, preventing the reflected laser from flowing back to the material surface and preventing photo-thermal secondary excitation. Through the above structural settings, the local plasma trap can significantly suppress the particle sputtering, photo-induced plasma rebound or energy secondary accumulation phenomena generated during the laser scribing process, improve the scribing edge clarity, stability and long-term reliability of the device, and is particularly suitable for the processing scenarios of multi-layer perovskite devices or flexible substrates.

[0039] Example 4 Based on Example 3, the conductive plate 4 is provided with a high-frequency thermal oscillation conductive layer, which is used to synchronously regulate the local thermal field distribution during the laser scribing process, relieve the thermal stress concentration, and improve the material ablation uniformity and boundary stability.

[0040] Specifically, the high-frequency thermal oscillation conductive layer includes a metal micro-resistance heating network disposed inside or on the surface of the conductive plate 4. This heating network is composed of periodically arranged micro-heating units, each micro-heating unit made of a high-resistance metal material (such as NiCr, Ti, Mo), with a size of 0.5–2 mm, a line width of 50–100 microns, and distributed in a strip or spiral shape. This heating network is electrically insulated from the main conductive plate through a heat-insulating medium (such as a polyimide layer or an alumina ceramic coating), but is structurally integrated on the conductive plate substrate to form a thermal conduction coupling. The above micro-heating network is powered by a group of high-frequency drive modules to generate a periodic pulse current with a frequency of 10–100 kHz and an adjustable amplitude, triggering a micro-scale periodic thermal expansion and contraction process, and then forming a low-amplitude, high-frequency temperature disturbance area on the surface of the conductive plate, called the "thermal oscillation area". This thermal oscillation synchronizes with the movement of the laser scanning path, and in real-time regulates the thermal diffusion channel below the scribed area, interrupting the local thermal gradient accumulation and reducing the thermal stress distortion. Preferably, the high-frequency thermal oscillation frequency is set to a multiple or sub-harmonic frequency of the laser pulse repetition frequency, so that the thermal field and the laser pulse action are synergistically superimposed, locally "preheating" the material before the laser pulse arrives, reducing its thermal impedance; and quickly "cooling" the area after the laser action, promoting the outward diffusion of heat and reducing the non-uniformity of material ablation and interface melting loss. Further, to improve the system response speed and thermal oscillation stability, a thermistor array or an infrared temperature sensor probe is provided on the back of the conductive plate to monitor the temperature distribution on the scribed path in real-time, and automatically adjust the frequency and power of the micro-heating network through a feedback control system to achieve dynamic thermal field stability management with closed-loop control.

[0041] Through the integration of this high-frequency thermal oscillation conductive layer, the problems of local heat accumulation and non-linear thermal response during the laser scribing process of perovskite solar cells are alleviated, the formation of microcracks and interface delamination is inhibited, the scribed line width consistency, boundary clarity, and device processing yield are improved, and it is particularly suitable for perovskite device structures with flexible substrates or more temperature-sensitive interface layers.

[0042] Example 5 Based on Examples 1-3, this example further introduces an ultrasonic assistance module. By integrating an ultrasonic generating device on the conductive plate 4, an ultrasonic micro-vibration disturbance is applied along the scribing direction during the laser scribing process, thereby improving the charge release efficiency, scribing quality, and enhancing the stability of the processing process.

[0043] On one side of the conductive plate 4 (parallel to the laser scanning path), a set of ultrasonic transducer components is installed. The model is a PZT ceramic transducer (frequency 1 MHz, power 1.5 W), which is firmly attached to the conductive plate 4 through an ultrasonic coupling adhesive layer. The transducer is driven by a high-frequency signal source. The ultrasonic frequency is set to 1 MHz, and the output amplitude is 2–5 μm (adjustable). The excitation period starts synchronously with the laser scribing. The ultrasonic waves excited by it propagate along the conductive plate in the form of surface shear waves in the copper plate, and the direction is consistent with the laser scribing path, ensuring that there is always a micro-vibration disturbance propagating along the scribing direction during the movement of the laser head.

[0044] Preferably, a piezoelectric ceramic ultrasonic transducer is arranged on one side of the conductive plate 4, with a working frequency of 1 MHz and an output power of 1.5 W. The ultrasonic transducer is attached to the lower surface of the conductive plate 4 through an ultrasonic coupling adhesive layer and is installed at an oblique angle of 30° relative to the normal of the conductive plate 4, so that the ultrasonic waves enter the conductive plate 4 obliquely. The oblique angle setting makes the ultrasonic waves propagate along an inclined path in the conductive plate 4 and the perovskite solar cell body structure, preferably exciting the shear wave and surface shear wave modes, forming an oriented stress disturbance band along the scribing direction below the laser scribing area, and forming a spatial coupling with the laser processing path. This structure can not only effectively enhance the charge disturbance and release efficiency, but also improve the thermal stress diffusion path under the action of laser heat, and enhance the scribing edge clarity and thermal damage control ability. The oblique angle coupling method can also reduce the ultrasonic reflection interference and standing wave effect, making the ultrasonic vibration energy more concentratedly transmitted to the processing area, which is particularly suitable for the high-precision laser scribing manufacturing of thermally and electrically dual-sensitive perovskite devices.

[0045] Preferably, an alternating magnetic field system can be introduced into the laser scribing device. Its structure includes a pair of electromagnetic coils or magnetic induction devices arranged on both sides of the laser irradiation area. The coil spacing is 5–10 mm, the magnetic field direction is perpendicular to the possible charge migration path, the magnetic field frequency is set in the range of 100 kHz to 5 MHz, and the magnetic induction intensity is controlled within the range of 10–100 mT. This magnetic field is turned on synchronously while the laser is irradiating. Through the action of the alternating magnetic field on the free electrons or plasma generated by the laser excitation, a periodic Lorentz force disturbance is formed, effectively breaking the local static charge distribution, promoting the charge to break away from its original position and migrate towards the conductive plate. This method can not only accelerate the charge release, relieve the electric field distortion, but also disrupt the recombination process of trap states and improve the interface stability. At the same time, the alternating magnetic field can also excite a weak inductive coupling effect, assisting the local diffusion of thermally excited particles, further reducing the superposition effect of laser thermal shock and charge aggregation, thereby improving the accuracy, uniformity and long-term stability of the laser scribing. This structure is particularly suitable for flexible perovskite batteries or interface recombination-sensitive devices.

[0046] In summary, the present invention provides a laser scribing device for perovskite solar cells. By arranging a grounded conductive plate 4 on the back of the perovskite solar cell body 1, the charges generated during the laser processing can be effectively discharged, and the electric field distortion and material damage can be inhibited. The conductive plate 4 can be made of a metal material and is in contact with the bottom electrode of the battery to further improve the charge conduction and heat diffusion efficiency. Further, a negative bias voltage can be applied to the conductive plate 4 to guide the charge migration. A metal protrusion structure 41 is arranged below the laser irradiation area to enhance the local electric field and heat dissipation capacity, and combined with the ultrasonic disturbance along the scribing direction, the scribing accuracy and processing stability are synergistically improved, which is suitable for the high-quality manufacturing of flexible and large-area perovskite batteries.

[0047] The foregoing is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present application shall be included within the scope of protection of the present application.

Claims

1. A laser scribing device for perovskite solar cells, comprising a perovskite solar cell body, a laser, and a focusing system. The laser emits a laser beam, and the focusing system focuses the laser beam onto the scribing area of the perovskite solar cell body, characterized in that: It further includes a conductive plate, which is located on the back of the perovskite solar cell body and is connected to the ground.

2. The perovskite solar cell laser scribing device according to claim 1, wherein: The conductive plate is electrically connected to the perovskite solar cell body through a conductive bonding material or a pressing structure.

3. The perovskite solar cell laser scribing device according to claim 1, characterized in that: The conductive plate is connected to an adjustable DC bias power supply for applying a negative bias voltage to the conductive plate during the laser scribing process.

4. The perovskite solar cell laser scribing device according to claim 1, wherein: A high-frequency thermal oscillation conductive layer is provided inside or on the surface of the conductive plate.

5. The perovskite solar cell laser scribing device according to claim 1, characterized in that: The conductive plate is provided with a convex structure on one side close to the laser irradiation area.

6. The perovskite solar cell laser scribing device according to claim 5, wherein: The surface of the convex structure is provided with a local plasma trap structure.

7. The perovskite solar cell laser scribing device according to claim 6, wherein: The convex structure is placed on the lower side of the laser irradiation area.

8. The perovskite solar cell laser scribing device according to claim 7, characterized in that: The width of the convex structure is greater than the laser scribing width.

9. The perovskite solar cell laser scribing device according to any one of claims 1-8, characterized in that: The conductive plate is connected to an ultrasonic generating device, and the ultrasonic generating device generates ultrasonic waves.

10. The perovskite solar cell laser scribing device according to claim 9, characterized in that: The ultrasonic waves are along the laser scribing direction.

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