Ge content and recess depth dependence of the band-to-band tunneling current in Si1-xGex/Si hetero-junctions

In this paper, a study of the leakage current through strained p⁺ n Si_1-xGe_x/Si hetero-junctions is presented. The reduction in the band gap, induced by stress forces, and the doping level at the hetero-interface, due to the use of halo implantations, are varied by changing the Ge content and the recess depth. A comparison between simulation results and experimental data is presented to analyze the suitability of the models used in this work. An optimization study to decrease the band-to-band tunneling component in the leakage current as a function of these two technological parameters is presented.