Two-dimensional computer modeling of single junction a-Si:H solar cells

Abstract

A two dimensional physically-based computer simulation of single junction pin amorphous silicon solar cells is presented using Sentaurus, Technology Computer-Aided Design (TCAD). The simulation program solves the Poisson, the continuity, and the current density equations by using a standard procedure for amorphous materials, including the continuous density of state model, Shockley-Read-Hall and Auger recombination mechanisms, and computes the generation function of electron-hole pairs from the optical parameters of each layer. The dependence of these optical parameters with the photon energy has been included, taking into account the doping level, thickness of each layer and their effect on cell efficiency. The simulator is applied to the analysis of a p-i-n single junction a-SiC:H/a-Si:H/a-Si:H solar cell, obtaining results comparable to one dimensional simulation results using AMPS (analysis of microelectronic and photonic structure)-1D. More advanced simulation models for novel solar cell devices such as tandem cells are in progress, with the aim of achieving an optimal design of solar cells based on amorphous materials or micro-/nanocrystalline layers.