CN209880575U

CN209880575U - MWT laser drilling mesa

Info

Publication number: CN209880575U
Application number: CN201920419132.6U
Authority: CN
Inventors: 黄智�; 周平平; 徐建华; 沈洪飞; 路忠林; 吴仕梁; 李质磊; 张凤鸣
Original assignee: Wuxi Ritong Photovoltaic Technology Co Ltd
Current assignee: Wuxi Ritong Photovoltaic Technology Co Ltd
Priority date: 2019-03-29
Filing date: 2019-03-29
Publication date: 2019-12-31
Anticipated expiration: 2029-03-29

Abstract

The utility model provides a MWT laser beam drilling mesa, the mesa that punches includes the mesa body, divide into solid area and fretwork district on the mesa body, the fretwork district distributes in the position department that punches in the laser hole, solid area distributes non-department of punching in the fretwork district, and is in it has the vacuum gas pocket to distribute on the solid area. In the aspect of the punching process, the table top is firstly modified, then the punching process is implemented, so that the contact area of the silicon wafer and the table top is greatly reduced, the influence of dust on the silicon wafer is effectively reduced, and the fragmentation rate and the hidden cracking rate of the manufacturing process can be effectively reduced.

Description

MWT laser drilling mesa

Technical Field

The utility model relates to a silicon solar cell technology technical field, concretely relates to supplementary material or consumptive material design of MWT silicon solar cell processing procedure.

Background

Currently, the crystalline silicon solar technology includes a heterojunction solar cell HIT, a back electrode contact silicon solar cell IBC, an emitter surrounding punch-through silicon solar cell EWT, a laser grooving buried gate cell, an inclined evaporation metal contact silicon solar cell OECO, a metal through-hole winding silicon solar cell MWT, and the like. Among them, MWT batteries are receiving more and more attention because of their high efficiency, small shading area and better appearance.

The MWT silicon solar cell transfers current carriers collected by the grid lines on the front side to the back side of the cell through laser drilling, so that the purpose of improving the conversion efficiency is achieved by reducing the shading area. Therefore, in order to realize the MWT battery structure, two functions of punching and hole conduction are required to be added in the conventional battery structure. Wherein, the perforation is usually realized by adopting a laser perforation mode at present; the hole conduction is usually realized by screen printing hole filling slurry and then co-sintering with the front electrode and the aluminum back surface field. For example, patent CN201410016190.6 provides a low-cost MWT battery preparation method, which only adds two processes to the traditional crystalline silicon battery production process to realize the MWT battery structure, and because the method has simple process and less equipment production, the method becomes the only mass production process of MWT batteries in the industry at present.

In the MWT cell process, laser drilling is the first process, and is different from the main and key processes of the conventional cell, and the purpose of the process is to prepare a certain number and arrangement of holes on a silicon wafer by laser, such as a 6 × 6 laser drilling lattice shown in fig. 1. The table panel related to the laser drilling process is shown in fig. 2, except for vacuum holes required for adsorbing a silicon wafer, as shown in fig. 2, a hollowed-out area is required to be set at a position on the table corresponding to the MWT battery drilling lattice, as shown in fig. 2. Silicon residue dust can be generated in the punching process, the thickness of the silicon wafer is reduced along with the increase of the productivity, and the influence of the dust on the process fragment rate is gradually prominent. How to reduce the influence of laser drilling on the production line index and cost reduction and efficiency improvement is very important.

SUMMERY OF THE UTILITY MODEL

The utility model provides a to the not enough of above-mentioned problem, provide a method and device that MWT laser beam drilling reduces latent splitting and is fit for the thin slice production.

The utility model provides a technical scheme as follows: the MWT laser drilling table top comprises a table top body, wherein the table top body is divided into a solid area and a hollow area, the hollow area is distributed at the drilling position of a laser hole, the solid area is distributed at the non-drilling position in the hollow area, and vacuum air holes are distributed in the solid area.

Furthermore, the laser holes are uniformly distributed on the table body in a matrix shape, the whole outer edge of all the laser holes is a solid area, and the solid area forms a closed curve outside the punching position; and a solid area is also arranged in the whole laser hole, the solid area divides all the laser holes into a plurality of parts, and the solid area in the laser hole is connected with the solid area at the outer edge.

Furthermore, the solid areas are distributed on the table top body in a shape like a Chinese character 'tian'.

Furthermore, a table top base is arranged below the punching table top, a vacuum air path is arranged in the table top base, the vacuum air path corresponds to the solid area, and vacuum air holes are distributed in the vacuum air path, so that the silicon wafer adsorption requirement required in the manufacturing process is met.

Preferably, 42 vacuum air holes are uniformly distributed in the solid area.

Based on the MWT laser drilling table board, the utility model also provides a laser drilling process, before drilling the MWT solar cell piece, the table board panel related to the MWT laser drilling process is hollowed out greatly, and the table board is processed into a solid area and a hollowed-out area; and processing the hollowed-out area into a working area of the punching process, processing vacuum air holes in the solid area, and installing vacuum air channels at corresponding positions of the solid area below the table board.

Preferably, the solid areas are distributed on the table top body in a shape like a Chinese character 'tian'.

The utility model discloses following beneficial effect has:

1. the table surface greatly reduces the contact area between the silicon wafer and the table surface, and effectively reduces the influence of dust on the silicon wafer, thereby effectively reducing the fragment rate and the hidden crack of the manufacturing process.

2. The table surface is provided with enough vacuum holes to ensure that the adsorption of the silicon wafer is unchanged.

3. Compared with the optimization through a high-power dust remover and a dust removal system, the method has the advantages of low investment and quick effect.

Drawings

FIG. 1 is a schematic illustration of laser drilling of a MWT cell;

FIG. 2 is a schematic illustration of a conventional MWT cell laser drilled mesa;

fig. 3 is a schematic diagram of the MWT cell laser drilling pattern of the present invention;

wherein: 1-laser drilling table surface, 2-solid area, 3-hollow area and 4-vacuum air hole.

Detailed Description

The technical solution of the present invention will now be fully described with reference to the accompanying drawings. The following description is merely exemplary of some, but not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative efforts belong to the scope of the present invention.

As shown in fig. 3, the utility model provides a MWT laser beam drilling mesa, the mesa that punches includes the mesa body, divide into solid area 2 and fretwork district 3 on the mesa body, fretwork district 3 distributes in the position department that punches in the laser hole, solid area 2 distributes non-department of punching in fretwork district 3 is in, and it has vacuum gas pocket 4 to distribute on the solid area 2.

Further, the laser holes are uniformly distributed on the table body in a matrix shape, a solid area 2 is arranged on the outer edge of the whole laser hole, and the solid area 2 forms a closed curve outside the punching position; and a solid area 2 is also arranged in the whole laser hole, the solid area 2 divides the whole laser hole into a plurality of parts, and the solid area 2 in the laser hole is connected with the solid area 2 at the outer edge.

Further, the solid areas 2 are distributed on the table body in a shape like a Chinese character 'tian'.

Further, a table base is arranged below the punching table, a vacuum air path is arranged in the table base, the vacuum air path corresponds to the solid area 2, and the vacuum air holes 4 are distributed in the vacuum air path, so that the silicon wafer adsorption requirement required in the process is met.

Preferably, 42 vacuum air holes 4 are uniformly distributed in the solid area 2.

In this embodiment, the MWT laser drilling mesa panel is designed as a hollow-out shape, and the external length of the solid area 2 is 168mm, and the width is 10 mm. 42 vacuum air holes 4 which are uniformly distributed are arranged in the field-shaped solid area 2, and the vacuum air holes 4 are connected with the vacuum air path of the table-board base to form vacuum, so that the silicon chip adsorption requirement required in the process of manufacturing is met.

The table surface greatly reduces the contact area between the silicon wafer and the table surface, and effectively reduces the influence of dust on the silicon wafer, thereby effectively reducing the fragment rate and the hidden crack of the manufacturing process.

Example 2

Based on the MWT laser drilling table board, the utility model also provides a laser drilling process, before drilling the MWT solar cell piece, the table board panel related to the MWT laser drilling process is hollowed out greatly, and the table board is processed into a solid area 2 and a hollowed-out area 3; the hollow area 3 is processed into a working area of the punching process, the solid area 2 is processed into a vacuum air hole 4, and a vacuum air path is arranged at a position corresponding to the solid area 2 below the table board.

Preferably, the solid areas 2 are distributed on the table body in a shape like a Chinese character tian.

The mesa panel involved in the MWT laser drilling process is largely hollowed out, as shown in fig. 3. The table top is divided into a solid area 2 and a hollow-out area 3.

The solid area 2 of the table top is directly designed at the periphery and the inner gap of the laser drilling lattice, in the embodiment, the solid area 2 is shaped like a Chinese character tian, the solid area 2 can also be in other shapes, such as a Chinese character ri, a Chinese character mu or other types of patterns, so as to avoid an MWT laser drilling lattice area, and a sufficient number of vacuum holes are arranged in the solid area 2, so that no difference in silicon wafer adsorption is ensured.

In the aspect of the punching process, the table top is firstly reformed, the punching process is implemented, a hollow area 3 is formed outside the solid area 2, the hollow area 3 is connected with the inner areas of different MWT laser punching dot matrixes, and meanwhile, the outer areas, which are outside the laser punching dot matrixes and are in contact with the silicon wafers, are also all hollowed. The hollow area 3 is greatly improved, and the influence of dust on the silicon wafer is reduced, so that the process fragment rate and the hidden cracking risk are reduced.

The above embodiments are provided only for the purpose of illustration, and not for the limitation of the present invention, and those skilled in the relevant art can make various changes or modifications without departing from the spirit and scope of the present invention, all belong to the scope of the present invention.

The foregoing shows and describes the general principles, essential features, and advantages of the invention. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are given by way of illustration only, and that various changes and modifications may be made without departing from the spirit and scope of the invention as defined by the appended claims, specification and equivalents thereof.

Claims

1. The MWT laser drilling table top is characterized by comprising a table top body, wherein the table top body is divided into a solid area and a hollowed-out area, the hollowed-out area is distributed at the drilling position of a laser hole, the solid area is distributed at the non-drilling position in the hollowed-out area, and vacuum air holes are distributed in the solid area.

2. The MWT laser drilling mesa of claim 1, wherein the laser holes are uniformly distributed on the mesa body in a matrix shape, and the whole outer edge of all the laser holes is a solid area, and the solid area forms a closed curve at the drilling position; and a solid area is also arranged in the whole laser hole, the solid area divides all the laser holes into a plurality of parts, and the solid area in the laser hole is connected with the solid area at the outer edge.

3. The MWT laser drilling platform of claim 1, wherein the solid areas are distributed on the platform body in a shape of Chinese character tian.

4. The MWT laser drilling table top of claim 1, wherein a table top base is arranged below the drilling table top, a vacuum gas path is arranged in the table top base, the vacuum gas path corresponds to the solid area, and vacuum gas holes are distributed in the vacuum gas path to meet the silicon wafer adsorption requirement required in the process.

5. The MWT laser drilling mesa of claim 1, wherein the solid areas have 42 vacuum holes distributed uniformly therein.