A simple general analytical solution for the quantum efficiency of front-surface-field solar cells

The optimisation of a FSF solar cell or a BSF thin film solar cell necessitates an understanding of the characteristics of an illuminated high-low junction. However, except for minority carrier reflection, the photocurrent collection property of the light-generated carriers in the high region by a high-low junction has rarely been treated previously. It is the purpose of this paper to present a simple solution for the contribution of the light-generated current from the high region, The model shows that a high-low junction may be very efficient in light-generated current collection, and this property is primarily responsible for the increase of the short wavelength quantum efficiency using a FSF. The effects of the FSF layer doping concentration and its thickness on the quantum efficiency are discussed by using the computed results, the optimisation of the FSF is then made. The calculations take into account the high doping effects of degeneracy and bandgap narrowing.