Effect of Plasma Treatment on Minority Carrier Lifetime of Gold-doped Silicon Wafers

Abstract

Gold impurities can introduce deep levels into the silicon forbidden band, and minority carriers are easily captured by these deep energy levels, resulting in the reduction of their lifetime, which in turn reduces the conversion efficiency of silicon solar cells. In this paper, it is found through experiments that plasma treatment of gold-doped silicon wafers can improve the minority carrier lifetime under certain conditions. The parameters of plasma treatment include, but are not limited to, the type of working gas, the treatment duration and the radio frequency power, etc. It is speculated that plasma treatment has a gettering effect on silicon wafers in this paper, and the mechanism of gettering is discussed.