Structure simulation of screen printed local back surface field for rear passivated silicon solar cells

Abstract

The research of this paper was focused on the simulation of screen printed Local Back Surface Field (LBSF) for the rear passivated solar cells. The thickness, homogeneity and cavity effect were studied. According to the simulation results, the thickness of LBSF should be at least 2 μm in order to gain high efficiency of solar cells. If LBSF was thick enough, the homogeneity of LBSF had less impact on the cell performance. However, the incomplete formation of LBSF layer would drastically decrease the open circuit voltage (V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">oc</sub> ) of cells. The thinnest part of an inhomogeneous LBSF should be 1 to 2 μm at the least. As for the influence of the cavities inside the local contacts, a single long cavity would cause a power loss of 8.20% to 11.15% relatively, and the cavity group made up of many long cavities would cause a power loss of about 11.53% to100% relatively.