Perovskite solar cell excimer laser P1 and P2 scribing method

Abstract

The invention discloses a perovskite solar cell excimer laser P1 and P2 scribing method. The method comprises the following steps: S1, preparing a transparent conductive layer; s2, determining a plurality of P1 scribing positions on the transparent conductive layer, and performing P1 scribing on the P1 scribing positions on the surface of the transparent conductive layer; s3, preparing a functional layer on the transparent conductive layer, determining a plurality of P2 scribing positions, and performing P2 scribing on the P2 scribing positions on the surface of the functional layer; wherein the excimer laser processing system comprises an excimer laser light source, a laser shaping system, a reflecting mirror or a spectroscope and a focusing mirror, and a light spot formed after deep ultraviolet excimer laser emitted by the excimer laser light source sequentially passes through the laser shaping system, the reflecting mirror or the spectroscope and the focusing mirror is a linear light spot. According to the invention, P1 and P2 scribing is carried out on the perovskite solar cell, and the processing precision and the processing efficiency can be improved.

Description

[Technical field]

[0001] The invention relates to an excimer laser P1 and P2 scribing method for a perovskite solar cell. [Background technology]

[0002] Perovskite solar cells generally include a multilayer structure of a transparent conductive layer, a functional layer, and an electrode layer. The functional layer includes a perovskite light absorption layer and an electron transport layer and a hole transport layer located on both sides of the perovskite light absorption layer. While expanding the area of ​​the perovskite solar cell, the performance of the device will be significantly reduced. This is mainly because the conductivity of the transparent conductive glass is relatively poor. Increasing the area increases the resistance and hinders the charge transfer. In order to reduce the impact of series resistance, a series module structure of multiple sub-cells is usually used. This structure is currently generally divided and connected by three laser scribings. These three scribings are usually called P1, P2, and P3. The P1 scribing disconnects the transparent conductive layer at the bottom of the adjacent sub-cells, and then prepares the functional layer in the middle. The P2 scribing disconnects the functional layer and exposes part of the transparent conductive layer to provide a channel for connecting the electrodes of the two adjacent sub-cells. After that, the electrode is evaporated and the metal electrode is disconnected by the P3 scribing to separate the metal electrodes of the adjacent sub-cells. The scribing area is an inactive area, called a dead zone.

[0003] At present, laser scribing mostly uses visible or infrared spot lasers for scanning and etching. However, there are the following shortcomings when scribing P1 and P2 of perovskite solar cells: 1. The materials in some structures have low absorption rates for some visible and infrared bands, resulting in part of the light penetrating the upper layer and being absorbed by the lower material when processing the upper structure, which in turn affects the processing accuracy; 2. When using spot scanning and etching, the material damage threshold, laser energy, frequency and mechanical structure movement speed restrict each other, and the processing efficiency is limited. When spot scanning and etching, edge collapse and peeling will occur on both sides of the scribing area; 3. Spot scanning and etching involves spot overlap, which will cause the boundary to be uneven and jagged, and the boundary is unclear; 4. Spot scanning and etching requires the workpiece to move with the workbench during laser processing. The scribing position will inevitably produce processing errors due to the movement of the workpiece, which will increase the dead zone width.

[0004] Therefore, the present invention is just produced to above disadvantages. [Summary of the invention]

[0005] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a method for scribing P1 and P2 lines of a perovskite solar cell using an excimer laser. The method can improve the processing accuracy and processing efficiency by scribing P1 and P2 lines of a perovskite solar cell.

[0006] Perovskite solar cells generally have a sandwich structure, including a functional layer in the middle and transparent conductive layers and electrode layers on both sides. The functional layer includes a perovskite light absorption layer and an electron transport layer and a hole transport layer located on both sides of the perovskite light absorption layer. The functional layer includes a perovskite light absorption layer, an electron transport layer and a hole transport layer. The perovskite light absorption layer usually has ABX 3 The structure of A is generally Cs + 、Ru + , K + , CH 3 NH 3 + , C(NH 2 ) 3 + 、CH(NH 2 ) 2 + A combination of one or more large-sized monovalent cations or groups; B is generally a small-sized divalent cation such as Pb 2 + Sn 2 + etc., X is generally such as I - Br - , Cl - A combination of one or more halogen element negative monovalent anions. The electron transport layer material is generally TiO 2 、ZnO、CdS、SnO 2 、In 2 O 3 ,WOx,CeO,PCBM,C 60 , C 70 The hole transport layer material is generally NiO, VO 2 、MoO 3 、CuS、CuSCN、CuO、Cu 2 O, CoO, TAPC, PTAA, PEDOT, Poly TPD, Spiro MeOTAD and other materials or a combination of one or more. The transparent conductive layer uses transparent conductive oxide (TCO) glass, and the electrode layer on the other side usually uses a metal electrode or TCO material. The material of TCO is generally a combination of one or more of ITO, FTO, AZO, IGO, BZO and the like. The metal electrode is generally a combination of one or more of Ag, Cu, Al, Cr, Ti, Ni and other materials.

[0007] The specific perovskite solar cell excimer laser P1, P2 scribing method includes the following steps:

[0008] S1: preparing a transparent conductive layer on a transparent glass substrate;

[0009] S2: determining multiple P1 scribing positions on the transparent conductive layer, placing the P1 scribing positions on the surface of the transparent conductive layer at the focus of the excimer laser processing system, and performing P1 scribing respectively, irradiating the transparent conductive layer with the excimer laser spot, removing the transparent conductive layer material in the scribing area, and disconnecting the transparent conductive layers of adjacent sub-cells, until all P1 scribings are completed;

[0010] S3: preparing a functional layer on the transparent conductive layer obtained in step S2, and determining a plurality of P2 scribing positions, placing the P2 scribing positions on the surface of the functional layer at the focus of the excimer laser processing system to perform P2 scribing respectively, irradiating the functional layer with the excimer laser spot, removing the functional layer material in the scribing area, disconnecting the adjacent sub-cell functional layers, until all P2 scribing is completed;

[0011] Among them, the excimer laser processing system includes an excimer laser light source, a laser shaping system, a reflector or a spectroscope, and a focusing mirror. The deep ultraviolet excimer laser emitted by the excimer laser light source passes through the laser shaping system, the reflector or the spectroscope, and the focusing mirror in sequence, and the light spot is a linear light spot.

[0012] The laser shaping system comprises a collimating beam expansion system, a linear light spot homogenizing system and a projection imaging system which are arranged in sequence.

[0013] An energy attenuation device is also provided between the excimer laser light source and the laser shaping system.

[0014] The excimer laser processing system also includes a microscopic observation device.

[0015] In step S2 , the linear light spot irradiates the transparent conductive layer in a manner of several pulses without damaging the transparent glass substrate.

[0016] In step S3 , the linear light spot irradiates the functional layer in a manner of several pulses without damaging the transparent conductive layer.

[0017] Compared with the prior art, the present invention has the following advantages:

[0018] 1. The present invention uses deep ultraviolet excimer laser as a light source when performing P1 and P2 scribing processing on perovskite solar cells. Currently, most materials used in perovskite solar cell structures have a significantly higher absorption rate for light sources in this band than for light sources in the visible and infrared bands. Therefore, using deep ultraviolet excimer laser as a light source can control the absorption depth and improve processing accuracy.

[0019] 2. The present invention adopts deep ultraviolet excimer laser for scribing processing. Since the single photon wavelength of deep ultraviolet excimer laser is short and the single photon energy is high, the deep ultraviolet excimer laser can break the material bonding of some perovskite solar cell structures, reduce the thermal effect from the removal mechanism, and further improve the processing accuracy. In addition, since it does not involve the peeling mechanism, there are no problems such as edge collapse and peeling.

[0020] 3. The large spot output by the deep ultraviolet excimer laser of the present invention is conducive to being converted into a linear spot through an optical shaping system. Compared with other high-frequency point spots that are marked by scanning, the deep ultraviolet excimer laser linear spot exposure method is used for marking, which can complete the processing within a few pulses and improve the processing efficiency.

[0021] 4. Marking with deep ultraviolet excimer laser linear spot exposure is a single or multiple exposure at the same position. There is no laser spot overlap, and a smooth and clear boundary can be obtained.

[0022] 5. Use deep ultraviolet excimer laser linear spot exposure to perform marking. Since the laser spot is a linear spot, there is no need to move the workpiece during laser exposure. Therefore, there is no processing error caused by mechanical structure movement, which can further improve the processing accuracy.

Brief Description of the Drawings

[0023] Figure 1 is a principle diagram of the optical path of the excimer laser processing system of the present invention;

[0024] Figure 2 is a schematic diagram of the laser shaping system of the present invention;

[0025] Figure 3 is a schematic diagram of a transparent glass substrate;

[0026] Figure 4 is a schematic diagram after a transparent conductive layer is prepared on a transparent glass substrate;

[0027] Figure 5 It is a schematic diagram of the excimer laser drawing the first P1 line on the transparent conductive layer;

[0028] Figure 6 It is a schematic diagram after the first P1 line is completed on the transparent conductive layer;

[0029] Figure 7 is a schematic diagram after completing multiple P1 lines on the transparent conductive layer;

[0030] Figure 8 is a schematic diagram of preparing a functional layer on a transparent conductive layer after P1 scribing is completed;

[0031] Fig. 9This is a schematic diagram of the excimer laser drawing the first P2 line on the functional layer;

[0032] Fig.10 This is a schematic diagram after the first P2 line is completed on the functional layer;

[0033] Fig.11 This is a schematic diagram after completing multiple P2 lines on the functional layer. [Specific implementation method]

[0034] The present invention will be further described below in conjunction with the accompanying drawings:

[0035] A perovskite solar cell excimer laser P1, P2 scribing method, comprising the following steps:

[0036] S1: preparing a transparent conductive layer 2 on a transparent glass substrate 1 on a workbench;

[0037] S2: determining a plurality of P1 scribing positions 3 on the transparent conductive layer, placing the P1 scribing positions 3 on the surface of the transparent conductive layer at the focus of the excimer laser processing system 4 to perform P1 scribing respectively, irradiating the transparent conductive layer 2 with the excimer laser 7 to remove the transparent conductive layer material in the scribing area, disconnecting the transparent conductive layers of adjacent sub-cells, until all P1 scribings are completed;

[0038] S3: preparing a functional layer 5 on the transparent conductive layer 2 obtained in step S2, and determining a plurality of P2 scribing positions 6, placing the P2 scribing positions 6 on the surface of the functional layer 5 at the focus of the excimer laser processing system 4 to perform P2 scribing respectively, irradiating the functional layer 5 with an excimer laser 7, removing the functional layer material in the scribing area, and disconnecting the adjacent sub-cell functional layers, until all P2 scribing is completed;

[0039] Among them, the excimer laser processing system 4 includes an excimer laser light source 41, a laser shaping system 42, a reflector 43 or a spectroscope, and a focusing mirror 44. The deep ultraviolet excimer laser emitted by the excimer laser light source 41 passes through the laser shaping system 42, the reflector 43 or the spectroscope, and the focusing mirror 44 in sequence, and the light spot is a linear light spot 71.

[0040] The excimer laser light source emits deep ultraviolet laser, which is shaped into a linear laser with a high aspect ratio by the laser shaping system 42, and is reflected to the focusing light path by the reflector 43 or the beam splitter, and is focused by the focusing mirror 44 to obtain a spot size and spot energy that meet the processing requirements, and the marking is performed after one or several exposures. Therefore, when the excimer laser is used to mark each P1 and P2 line, the length of the linear spot 71 can be adjusted to correspond to the length of each required P1 and P2 line, and the deep ultraviolet excimer laser is irradiated to the marking position in a pulsed manner, and the P1 and P2 marking process can be completed without moving the workbench or overlapping the linear spot, with high processing accuracy and high efficiency.

[0041] In step S2 , the linear light spot irradiates the transparent conductive layer 2 in a manner of several pulses without damaging the transparent glass substrate 1 . In step S3 , the linear light spot irradiates the functional layer 5 in a manner of several pulses without damaging the transparent conductive layer 2 .

[0042] The laser shaping system 42 includes a collimating and expanding system 421, a linear light spot homogenizing system 422, and a projection imaging system 423, which are arranged in sequence. The expanding and collimating system 421 can adjust the size of the laser light spot while compressing the divergence angle of the deep ultraviolet excimer laser so that the major and minor axes of the laser beam match the working surface. The linear beam homogenizing system 422 improves the uniformity of the original laser beam intensity distribution through a lens array and changes the original light spot shape into a linear shape. The projection imaging system 423 can image a larger light spot at the working surface, optimize the light spot morphology, and further increase the laser energy density at the working surface.

[0043] An energy attenuation device 45 is also provided between the excimer laser light source 41 and the laser shaping system 42. The energy attenuation device 45 is used to control the laser energy of the light source to meet different scribing requirements. The excimer laser processing system 4 also includes a microscopic observation device 46 for determining the processing position and monitoring whether the processing position is accurate.

[0044] The functional layer includes a perovskite light absorbing layer, an electron transport layer and a hole transport layer. The perovskite light absorbing layer usually has ABX 3 The structure of A is generally Cs + 、Ru + , K + , CH 3 NH 3 + , C(NH 2 ) 3 + 、CH(NH 2 ) 2 +A combination of one or more large-sized monovalent cations or groups; B is generally a small-sized divalent cation such as Pb 2 + Sn 2 + etc., X is generally such as I - Br - , Cl - A combination of one or more halogen element negative monovalent anions. The electron transport layer material is generally TiO 2 、ZnO、CdS、SnO 2 、In 2 O 3 ,WOx,CeO,PCBM,C 60 , C 70 The hole transport layer material is generally NiO, VO 2 、MoO 3 、CuS、CuSCN、CuO、Cu 2 O, CoO, TAPC, PTAA, PEDOT, Poly TPD, Spiro MeOTAD and other materials or a combination of one or more thereof.

[0045] Since solar cells generate electricity using the photoelectric effect, the transparent conductive layer usually uses transparent conductive oxide (TCO) glass, and the other electrode usually uses a metal electrode or TCO material. TCO materials are generally a combination of one or more materials such as ITO, FTO, AZO, IGO, BZO, etc. Metal electrodes are generally a combination of one or more materials such as Ag, Cu, Al, Cr, Ti, Ni, etc.

Claims

1. A method for scribing P1 and P2 lines of a perovskite solar cell using an excimer laser, characterized in that: The steps include: S1: preparing a transparent conductive layer (2) on a transparent glass substrate (1) on a workbench; S2: determining a plurality of P1 scribing positions (3) on the transparent conductive layer, placing the P1 scribing positions (3) on the surface of the transparent conductive layer at the focus of an excimer laser processing system (4) to perform P1 scribing respectively, irradiating the transparent conductive layer (2) with an excimer laser (7), removing transparent conductive layer material in the scribing area, and disconnecting the transparent conductive layers of adjacent sub-cells until all P1 scribing is completed; S3: preparing a functional layer (5) on the transparent conductive layer (2) obtained in step S2, and determining a plurality of P2 scribing positions (6), placing the P2 scribing positions (6) on the surface of the functional layer (5) at the focus of the excimer laser processing system (4) to perform P2 scribing respectively, irradiating the functional layer (5) with an excimer laser (7), removing the functional layer material in the scribing area, and disconnecting the adjacent sub-cell functional layers, until all P2 scribing is completed; The excimer laser processing system comprises an excimer laser light source (41), a laser shaping system (42), a reflector (43) or a beam splitter, and a focusing mirror (44); the deep ultraviolet excimer laser emitted by the excimer laser light source (41) passes through the laser shaping system (42), the reflector (43) or the beam splitter, and the focusing mirror (44) in sequence, and the light spot is a linear light spot (71).

2. The method for scribing P1 and P2 lines of a perovskite solar cell using excimer lasers according to claim 1, characterized in that: The laser shaping system (42) comprises a collimating beam expansion system (421), a linear light spot homogenization system (422) and a projection imaging system (423) which are arranged in sequence.

3. The method for scribing P1 and P2 lines of a perovskite solar cell according to claim 1, characterized in that: An energy attenuation device (45) is also provided between the excimer laser light source (41) and the laser shaping system (42).

4. The method for scribing P1 and P2 lines of a perovskite solar cell according to claim 1, characterized in that: The excimer laser processing system (4) further comprises a microscopic observation device (46).

5. The method for scribing P1 and P2 lines of a perovskite solar cell according to claim 1, characterized in that: In step S2, the linear light spot (7) irradiates the transparent conductive layer (2) in a manner of several pulses without damaging the transparent glass substrate (1).

6. The method for scribing P1 and P2 lines of a perovskite solar cell according to claim 1, characterized in that: In step S3, the linear light spot (7) irradiates the functional layer (5) in a manner of several pulses without damaging the transparent conductive layer (2).

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