Back-junction back-contact n-type silicon solar cells with screen-printed aluminum-alloyed emitter

Abstract

We introduce an n-type Si back-junction back-contact solar cell based on an Al-doped p+ rear emitter fabricated by means of screen-printing and firing instead of the commonly applied high-temperature boron diffusion. In order to demonstrate the applicability of this easy-to-fabricate p+ emitter to a back-junction back-contact solar cell we present experimental results showing 19.0% cell efficiency. The structuring of the cell is performed by laser processing omitting any photolithography. Using two-dimensional device simulation we determine a realistic efficiency limit of 21.6% for this cell type.