A method for adjusting solar cell grid line offset and its application

Abstract

The invention discloses a method for adjusting solar battery grid line offset, which includes printing the grid line on a silicon wafer by using a screen plate; measuring the distance x between adjacent laser grooves and the distance between the centers of adjacent grid lines respectively distance y 1 , the distance y between the endpoints of adjacent grid lines 2 ; Calculate the first offset distance δ between the laser groove and the grid line 1 and the second offset spacing δ 2 ;Judge according to the offset spacing, and adjust the PT value and / or tension value of the screen. Correspondingly, the present invention also discloses the application of the above method for adjusting the solar cell grid line offset in the solar cell production process. The adjustment method of the invention can significantly reduce or eliminate the offset between the electrode grid lines and the laser groove, and improve the carrier collection ability of the electrode grid lines while meeting the battery appearance requirements.

Description

technical field [0001] The invention relates to the field of solar cell electrode printing, in particular to a method for adjusting solar cell grid offset and its application. Background technique [0002] Screen printing is a commonly used solar cell printing technology at present. Its basic operation process is: place the silicon wafer with laser grooves on the workbench, pour the slurry on the screen above the workbench, and then use a scraper to place it on the workbench. Apply a certain pressure on the screen, and at the same time move the scraper from one end of the screen to the other, the slurry can be squeezed from the mesh of the graphic part onto the silicon wafer, thereby completing the screen printing. In the current printing process, the printing effect is mostly adjusted through parameters such as printing pressure, printing pitch, printing speed, and printing height. [0003] On the other hand, with the development of solar cell technology, laser heavy dopin...

AI Technical Summary

Problems solved by technology

The existing screen printing process, when printing laser grooves, often has a large offset, which not only cannot meet the requirements for the appearance of the cell, but also easily causes carrier collection difficulties and carrier transport losses

[0004] In the prior art, this problem is often solved by widening the width of the laser grooves. For example, the width of the existing laser grooves is mostly 120-300 μm to reserve a larger printing space, but this will reduce the number of electrode grid lines and reduce the current carrying capacity. The amount of sub-collection is small, which reduces the efficiency of the cell; at the same time, it also increases the risk of cracks in the silicon wafer

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