CN113192857B

CN113192857B - Method for judging failure of crystalline silicon solar cell

Info

Publication number: CN113192857B
Application number: CN202110422772.4A
Authority: CN
Inventors: 张泽晖; 王鹏
Original assignee: Shanxi Luan Solar Energy Technology Co Ltd
Current assignee: Shanxi Luan Solar Energy Technology Co Ltd
Priority date: 2021-04-20
Filing date: 2021-04-20
Publication date: 2023-05-12
Anticipated expiration: 2041-04-20
Also published as: CN113192857A

Abstract

The invention relates to the field of solar cell production. A method for judging failure of a crystalline silicon solar cell, wherein the crystalline silicon solar cell is produced by adopting SE+PERC, if all the following conditions can be met, the crystalline silicon solar cell is a good cell, otherwise, the crystalline silicon solar cell is a failed cell, and the appearance of the cell is not provided with obvious clear SE fine grid lines; secondly, placing the battery piece under a lens of a secondary microscope, selecting light source brightness of 30%, selecting 96X by using a magnifier, and observing that no obvious bright spots or bright spots exist in the area except the grid line; and thirdly, placing the coated blue film under a lens of a secondary microscope, selecting 50% of light source brightness, selecting 96X of a magnifier, and observing that the grid line light spots are full and no unfilled corner exists.

Description

Method for judging failure of crystalline silicon solar cell

Technical Field

The invention relates to the field of solar cell production.

Background

Along with the development of the crystalline silicon solar cell manufacturing technology, the SE PERC technology is emerging, so that the conversion efficiency of the cell is improved, and meanwhile, more and more defects of the cell in the production process are exposed. In the SE process, the difference of the appearance and brightness of the light spots presented by the SE is always found by daily monitoring, and the abnormal problem points of mass production are necessary to be detected through experimental tracking.

Disclosure of Invention

The technical problems to be solved by the invention are as follows: and judging whether the crystalline silicon solar cell fails or not.

The technical scheme adopted by the invention is as follows: a method for judging failure of a crystalline silicon solar cell, wherein the crystalline silicon solar cell is produced by adopting SE+PERC, if the following conditions can be fully met, the crystalline silicon solar cell is a good cell, otherwise, the crystalline silicon solar cell is a failed cell

The appearance of the battery piece does not have obvious clear SE fine grid lines;

secondly, placing the battery piece under a lens of a secondary microscope, selecting light source brightness of 30%, selecting 96X by using a magnifier, and observing that no obvious bright spots or bright spots exist in the area except the grid line;

and thirdly, placing the coated blue film under a lens of a secondary microscope, selecting 50% of light source brightness, selecting 96X of a magnifier, and observing that the grid line light spots are full and no unfilled corner exists.

The fact that the appearance of the battery piece does not have obvious clear SE thin grid lines means that the thin grid lines cannot be seen by naked eyes, the thin grid lines can be seen under the condition of polishing, a specific judgment standard is that a digital camera is adopted to photograph 800 ten thousand pixels or higher pixels of the crystalline silicon solar battery piece, a computer is adopted to extract characteristics of photographed images, pixel difference values of pixels in the area where the thin grid lines are located and unexpected areas of the grid lines are compared with a first set value, and the fact that the pixel difference values are smaller than or equal to the set value indicates that the appearance of the battery piece does not have obvious clear SE thin grid lines.

The absence of obvious bright spots and bright spots means that the difference of pixel values in the areas outside the grid lines does not exceed a second set value, and the bright spots can be identified by human eyes in practice through computer identification after photographing. But require a skilled technician and a certain experience.

Observing that the grid line light spots are full and have no unfilled corners means that the blue film piece after the film plating of the qualified crystalline silicon solar cell piece is selected is placed under the secondary microscope lens, the light source brightness is selected to be 50%, the magnifier is selected to be 96X, photographing is carried out to obtain a standard picture, the cell piece to be detected is placed under the secondary microscope lens, the light source brightness is selected to be 30%, the magnifier is selected to be 96X, photographing is carried out to obtain a picture to be detected, the standard picture and the picture to be detected are extracted through computer features, the grid line area of the standard picture and the grid line area of the picture to be detected are compared in each corresponding place, if the pixel difference value of the grid line area and the grid line area of the picture to be detected in a certain place is larger than a third set value, the appearance of the cell piece is indicated to have obvious clear SE fine grid lines, otherwise, the appearance of the cell piece is indicated to have no obvious clear SE fine grid lines.

The beneficial effects of the invention are as follows: the invention can effectively discover the battery piece with low failure rate in time, reduce defective products and improve the quality of the battery piece.

Detailed Description

By observing whether the appearance of the SE rear battery piece has obvious clear SE fine grid lines or not, if so, the SE machine energy light path can be directly reworked and debugged.

And placing the SE rear battery piece under a lens by means of a secondary microscope, selecting the light source brightness to be 30%, and selecting the magnifier to be 96X. And (3) the spot brightness displayed by the imaging of the non-grid line area under the secondary element, if the imaging has obvious bright spots, the bright spots appear. And (5) reworking the battery piece after the SE is processed, and adjusting the SE machine. And (5) daily monitoring the spot bright spots which are shown by the silicon wafer after the found SE. In the production process, the laser emission energy of the SE machine is gradually lost and reduced, when the energy is reduced to a certain degree, energy focusing can be generated, a little of energy is converged, and the silicon wafer is greatly damaged, so that low failure is formed.

After passing through the coated blue film, the blue film passes through an SE machine, and then the brightness of a light source is selected to be 50% by means of a secondary microscope, and the X-ray is selected to be 96. Whether the light spots displayed by the secondary lower grid line imaging are full (namely whether uniform regular patterns are formed) or not, and whether corners are unfilled or not. If the size is uneven, the SE machine should be adjusted if one of the conditions occurs.

And (3) daily monitoring the light spot defect of the silicon wafer after the film coating. In the production process, the laser emission energy of the SE machine table is gradually lost and reduced, and other factors such as abrasion, dust and the like of the vibrating mirror and the refracting mirror can cause light spot missing in the produced silicon wafer.

Claims

1. The method for judging the failure of the crystalline silicon solar cell adopts SE+PERC production, and is characterized in that: if all the following conditions are satisfied, the crystalline silicon solar cell is a good cell, otherwise, the crystalline silicon solar cell is a failed cell

The appearance of the battery piece does not have obvious clear SE fine grid lines; the fact that the appearance of the battery piece is not provided with the obvious clear SE fine grid line means that the fine grid line cannot be seen by naked eyes, the fine grid line can be seen under the condition of polishing, the specific judgment standard is that a digital camera is adopted to photograph 800 ten thousand pixels or higher pixels of the crystalline silicon solar battery piece, a computer is adopted to extract characteristics of photographed images, the pixel difference value of the area where the fine grid line is located and the pixel difference value of the area outside the grid line are compared with a first set value, and the fact that the pixel difference value is smaller than or equal to the set value indicates that the appearance of the battery piece is not provided with the obvious clear SE fine grid line;

secondly, placing the battery piece under a lens of a secondary microscope, selecting light source brightness of 30%, selecting 96X by using a magnifier, and observing that no obvious bright spots or bright spots exist in the area except the grid line; the absence of an obvious bright spot means that the difference of pixel values in the areas outside the grid lines does not exceed a second set value;

thirdly, placing the coated blue film under a lens of a secondary microscope, selecting 50% of light source brightness, selecting 96X of a magnifier, and observing that the grid line light spots are full and no unfilled corner exists; full, i.e., grid line, speckles can form a uniform regular pattern.