Highly Efficient ZnTe Solar Cell with PbTe BSF

Abstract

Zinc Telluride (ZnTe) is a very promising binary semiconductor material is chosen for the ultra-thin approach due to its high absorption coefficient, wider band gap of 1.42 eV and higher thermal stability. This paper illustrates the numerical analysis of the insertion of a thin Lead Telluride (PbTe) BSF layer between the ZnTe absorber layer and the back contact in the ultra-thin ZnTe solar cell is investigated by the wxAMPS simulation software. This PbTe BSF layer offers an extra hole tunneling action that produces a quasi ohmic contact near to the back contact and BSF region. The BSF layer minimizes the recombination losses and the quasi ohmic contact increases the carrier collection that improves the cell performance of the ZnTe solar cell. The simulated result was found 17.55% efficiency for the proposed ultra-thin cell without BSF and the improved cell efficiency was gained 22.15% for only 0.9 µm ZnTe layer with PbTe BSF layer. Besides, it was found higher thermal stability of the proposed cells where the temperature coefficient is of (-0.029%/°k).