Key parameters of textured silicon solar cells of 26.6% photoconversion efficiency

A new approach to modeling the parameters of high efficiency textured silicon solar cells (SCs) has been presented. Unlike conventional optimization formalisms, our approach additionally includes such important factors as the non-radiative Auger recombination of excitons via deep impurity levels as well as electron-hole pairs recombination in the space charge region. A simple phenomenological expression offered by us earlier for the external quantum efficiency of the textured silicon solar cells with account of the photocurrent in the long-wave part of the absorption spectrum has been also used. Applying this approach, the key parameters of textured silicon SCs, namely: short-circuit current, open-circuit voltage and photoconversion efficiency, have been theoretically determined. The proposed formalism allows calculating the thickness dependence of photoconversion efficiency, which is in good agreement with the experimental results obtained for the heterojunction SCs with the record photoconversion efficiency of 26.6%. The offered approach and the results of applying this phenomenological expression for the external quantum efficiency of the photocurrent in the long-wave part of the absorption spectrum can be used to optimize the characteristics of high efficiency textured SCs based on monocrystalline silicon.