High efficiency all‐GaAs solar cell

Abstract

AbstractThe reduction of surface recombination in GaAs solar cells is known to be a major concern for photovoltaic cells designers. A common technique used to reduce this effect is to cover the GaAs surface with a wide band gap window layer, therefore the creation of a heterojunction. To avoid a heterojunction with its inconveniences; interface surface states, poor photon absorption in addition to the technological exigencies, one can use an all‐GaAs solar cell. In this type of structure, a thin highly doped layer is created at the surface known as a front surface field (FSF). The main role of an FSF layer is to reduce the effect of front surface recombination and the enhancement of light‐generated free carriers' collection. This is achieved by the drastic reduction of the effective recombination at the emitter upper boundary. In this work, a simple analytical model is used to simulate the influence of the FSF layer on GaAs solar cell parameters; photocurrent, open circuit voltage and energy conversion efficiency. The effects of the FSF layer doping density and its thickness on the cell performance are discussed by using computed results. Copyright © 2010 John Wiley & Sons, Ltd.