Atomistic simulation of doping effects on growth and charge transport in Si/Ag interfaces in high-performance solar cells

Abstract

We present the results of a first-principles atomistic simulation study of the effects of phosphorus doping on the silver/silicon interface as found in high-performance solar cells. Calculating the interfacial stabilities of the (110)/(110) and (111)/(111) interfaces we demonstrate how the presence of phosphorus increases the nucleation rate of silver crystallites and how the relative stabilities of the interfaces depend on the doping. We then calculate the electronic structure of the interfaces, demonstrating how the presence of phosphorus leads to a buildup of positive charge in the silicon and an opposite negative charge in the silver. Finally we show how this charge buildup significantly affects the $n$-type Schottky barriers at the interfaces, in both cases lowering the Schottky barrier by more than 100 meV.