A Multiscale Model to Study Transport in Silicon Heterojunction Solar Cells

Abstract

Silicon heterojunction solar cells comprised of crystalline silicon and a thin amorphous silicon top layer, have consistently achieved record device efficiencies in recent years for Si devices. In particular, the intrinsic amorphous layer provides passivation at the a-Si/c-Si heterointerface that facilitates high $\mathrm {V}_{\mathrm {o}\mathrm {c}}'\mathrm {s}$. However, this heterointerface also results in high fields where hot carrier effects may dominate, in contrast to low-field diffusive transport which is prevalent in the bulk of the device. In this paper we present a fully coupled self-consistent drift-diffusion-Monte Carlo (DD-MC) solver that connects the Lowfield physics of the drift-diffusion model with the high-field physics of the Monte Carlo domain at the interface.