Light-induced degradation in p-type gallium co-doped solar grade multicrystalline silicon wafers and solar cells

¹ School of Energy Research Xiamen University, 361005 Xiamen, P.R. China
² College of Physics and Mechanics and Electrics Xiamen University, 361005 Xiamen, P.R. China

^a e-mail: cchen@xmu.edu.cn

Received: 30 July 2013
Revised: 25 October 2013
Accepted: 13 November 2013
Published online: 16 December 2013

Abstract

This letter focuses on the evolution under illumination of the minority carrier lifetime and conversion efficiency of p-type gallium (Ga) co-doped solar grade multicrystalline silicon wafers and solar cells. We present experimental data regarding the concentration of boron-oxygen (B-O) defects in this silicon when subjected to illumination, and the concentration was found to depend on [B]-[P] rather than [B] or the net doping p0([B] + [Ga] – [P]). This result implies that the compensated B is unable to form the B-O defect. Minority carrier lifetime and EQE measurements at different degradation states indicate that the B-O defect and Fe-acceptor pairs are the two key centers contributed to LID in this material.