Study of GeSn Alloy for Low Cost Monolithic Mid Infrared Quantum Well Sensor

Abstract

This paper focuses on theoretical study of Tin incorporated group IV alloys particularly GeSn and design of quantum well sensor for mid infrared sensing applications. Initially, the physics behind the selection of material for midinfrared sensor is explained. The importance of controlling strain in GeSn alloy is also explained. The physical background and motivation for incorporation of Tin(Sn) in Germanium is briefly narrated. Eigen energy states for different Sn concentrations are obtained for strain compensated quantum well in G valley conduction band (GCB), heavy hole (HH) band and light hole (LH) band by solving coupled Schrödinger and Poisson equations simultaneously. Sn concentration dependent absorption spectra for HH- GCB transition reveals that significant absorption observed in mid infrared range (3-5 µm). So, Ge1-x Snx quantum well can be used for mid infrared sensing applications.

Keywords

• GeSn
• Strain
• Midinfrared
• Quantum well
• Tin incorporated group IV alloy.