Testing method of crystalline silicon solar cell diffusion dead layer

Abstract

The invention discloses a testing method of a crystalline silicon solar cell diffusion dead layer. The method comprises the following steps that 1, after a to-be-tested silicon wafer is subjected to diffusion and impurity glass layer removing, square resistance of the to-be-test silicon wafer is tested through a four probe method and denoted as R1; 2, the silicon wafer in the step 1 is subjected to heat treatment, and a doping dead layer of the silicon wafer is activated; 3, square resistance of the silicon wafer obtained in the step 2 is tested through the four probe method again and denoted as R2; 4, when R1 is larger than R2, and (R1-R2) / R1 is larger than or equal to 3%, it is determined that a diffusion dead layer exists in a crystalline silicon solar cell, and the ratio of the concentration of impurity atoms in the diffusion dead layer to the concentration of impurity atoms in the doping layer is (R1-R2) / R1. According to the testing method, by means of the mode of activating the doping dead layer, square resistance changes before and after activation or changes of ECV distribution are tested, and therefore weather the doping technology forms a dead layer or not is determined.

Description

technical field [0001] The invention relates to a method for testing a diffusion dead layer of a crystalline silicon solar cell, belonging to the technical field of solar cells. Background technique [0002] Conventional fossil fuels are increasingly depleted. Among all sustainable energy sources, solar energy is undoubtedly the cleanest, most common and most potential alternative energy source. At present, among all solar cells, crystalline silicon solar cells are one of the solar cells that have been widely commercialized. This is due to the extremely abundant reserves of silicon materials in the earth's crust. Cells have excellent electrical and mechanical properties, therefore, crystalline silicon solar cells occupy an important position in the field of photovoltaics. [0003] The existing manufacturing process of crystalline silicon solar cells is: surface cleaning and texturing, diffusion, cleaning and etching to remove edges, anti-reflection coating, screen printing,...

AI Technical Summary

Problems solved by technology

There are a large number of interstitial atoms, dislocations and defects in the diffusion dead layer, and the minority carrier lifetime is low. The photogenerated carriers emitted by sunlight in the dead layer are all recombined, resulting in a decrease in the conversion efficiency of the cell.

[0004] However, for different diffusion processes, whether or not to form a dead layer and the thickness of the formed dead layer are completely different, and the dead layer will affect the electrical performance, but in the prior art, it is usually impossible to directly reflect the electrical properties of the battery after diffusion. Whether there is a dead layer on the PN junction or how many dead layers exist