12 April 1996 Superlattice IR detectors: a theoretical view
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Abstract
A theoretical program useful for predicting limiting performance of HgCdTe, InAs/InGaSb Type II superlattices and QWIP IR detectors is reviewed. Its principal ingredients include the calculation of bulk and superlattice band structures, absolute interband and intersubband optical absorption coefficients, radiative recombination neglecting photon recycling, non- radiative AM-1 and AM-7 Auger processes with or without the participation of shallow impurity levels, and the detectivity. The superlattice is viewed as a periodic lattice whose relevant band structure is described by K(DOT)p perturbation theory. Valence band strain splitting greater than the band gap is particularly important in suppressing AM-7 transitions. HgCdTe IR detectors are clearly superior to Type II superlattices in the MWIR. The band gap in Type II superlattices is due to intra-layer carrier confinement and is determined by layer widths. The resulting greater band gap uniformity and theoretically higher operating temperatures is promising for LWIR and VLWIR applications.
© (1996) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Henry Ehrenreich, Michael E. Flatte, Christoph H. Grein, "Superlattice IR detectors: a theoretical view", Proc. SPIE 2685, Photodetectors: Materials and Devices, (12 April 1996); doi: 10.1117/12.237712; https://doi.org/10.1117/12.237712
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