Influences of Aluminum Rear Contact and Back Surface Field Formation for PERC Solar Cells

Abstract

In this paper, we demonstrate the aluminum rear contact with different widths grid and full-area on the p-type passivated emitter and rear cells (PERC). We analysis the rear contact and back surface field (BSF) formation on PERC cells. We observe a reduced number of voids in the Al-Si eutectic layer by using grid Al, compared with full-area Al layer. The open-circuit voltage (${V}_{{oc}}$) and short current density (${J}_{{sc}}$) of PERC+ solar cells improve up to 4 mV and near 0.19 mA/cm2 when using local grid contact.