Advantages of the HgTe-CdTe superlattice as an infrared detector material

Abstract

The HgTe-CdTe superlattice is found to exhibit properties superior to those of the (Hg, Cd)Te alloy as an infrared detector material. A calculation shows that the superlattice tunneling length is shorter than that of the alloy with the same band gap. For a given cutoff wavelength tolerance, we find that less fractional precision is needed in the superlattice control parameter (layer thicknesses) than in the alloy control parameter (composition). Also, p-side diffusion currents are expected to be reduced due to the larger superlattice electron effective mass.