Improved Ghost Plating of Light-Induced Plating on Crystalline Silicon Solar Cells by SiO₂/SiN Selective Etching

Abstract:

In this paper, the ghost plating problems of crystalline silicon solar cells is studied in theory and experiment. After laser doping process, a pretreatment process is needed to remove SiO₂ in the heavy doping area and keep SiN mask simultaneously by using chemical solution containing HF. Otherwise, the unexpected non-heavy-doping area would be plated with silver, resulting in the ghost plating problems. The mechanism of HF etching SiO₂ and SiN is analyzed and the feasibility of selective etching is discussed. By changing the main aspects of affecting the etching rate, the ghost plating of crystalline silicon solar cells is improved.

• Periodical: Applied Mechanics and Materials (Volumes 71-78)
• Pages: 2290-2293
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.71-78.2290
• Online since: July 2011
• Authors: Tao Li, Chun Lan Zhou, Zhen Gang Liu, Wen Jing Wang, Yang Song, Zhi Hua Gao, Ye Duan, You Zhong Li
• Keywords: Crystalline Silicon Solar Cells, Ghost Plating, Light-Induced Plating, Selective Etching

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