Recently,  CSG PVTECH  successfully obtained an invention patent authorization, the patent name is "Method and System for Impurity Removal in Silicon Wafers", and the patent number is ZL 2022 1 0646479.0.

The invention discloses a method and a system for removing impurities in a silicon wafer, and relates to the technical field of batteries. The method comprises the following steps: setting a processing container provided with a plurality of silicon wafers into a vacuum state; Introducing nitrogen into a processing container in a vacuum state, and performing temperature rise and fall pretreatment, so that part of impurities in the silicon wafer are diffused in the nitrogen and mixed with the nitrogen; Pumping nitrogen mixed with impurities from the processing container; Introducing argon into the processing container after nitrogen extraction, performing internal gettering treatment and cleaning to obtain clean silicon wafers. Nitrogen is introduced into the processing container in vacuum state, and the impurities in the silicon wafer are diffused to nitrogen after being heated and expanded, and are discharged with the nitrogen when being vacuumized. Then argon is introduced for internal gettering treatment, so that most of the remaining impurities can remain on the surface of the silicon wafer.

The acquisition of this patent is the result of continuous innovation and exploration and research of  CSG PVTECH . The patent can effectively remove impurities in the silicon wafer, improve the reliability of the silicon wafer battery and improve the production efficiency. It has laid a solid foundation for the company to improve product quality and enhance market competitiveness.

(Text/Tan Li, R&D Department)