Direct-gap Ge/GeSn/Si and GeSn/Ge/Si heterostructures

摘要: Abstract A theoretical proposal is given for creating direct-gap semiconductor layers in silicon-based Group IV heterostructures. Based upon recent bandstructure calculations pseudomorphic Ge/GeSi and GeSi/Ge, we predict a strain-induced Γc-Lc crossover (λg ∼ 2.2 μm) tensile Ge/Ge0.87Sn0.13 compressive Ge0.98Sn0.02/Ge. We used linear extrapolation of band-edge curves. The structures are potentially useful laser diodes, electrooptic modulators, photodetectors.