The effect of Sb content in InAs_(1-x)Sb_x/GaSb Type-II Superlattices

摘要

InAs/GaSb type-II. superlattices materials have large quantum efficiency and responsivity, and smaller tunneling current and Auger recombination rate. However, the lattice constants of two components of the SLs are not exactly the same, which would introduce strain between each layer. InSb is introduced into InAs component, forming InAs_(1-x)Sb_x/GaSb to free the strain. Band structure of SLs is computed with the use of K.P theory under the envelop-function approach. Electron effective mass and relative absorption are also calculated with Sb content varying from 0 to 0.2. The strain is almost negligible when the Sb content is 0.09, electron effective mass and relative absorption increase as Sb content increases. Dark current is analyzed under different temperature.