Lateral diffusion of minority carriers in nBn based type-II InAs/GaSb strained layer superlattice detectors

We report on the investigation of lateral diffusion of minority carriers in nBn based InAs/GaSb strained layer superlattice photodetectors. Values of diffusion length of minority carriers were extracted from temperature dependent I-V measurements. The behavior of diffusion length as a function of applied bias, temperature, and composition of the barrier layer and the values ranging by two orders of magnitude from 77 to 250 K at the same value of applied bias were investigated. The obtained results suggest that at this point the lateral diffusion current could be the limiting factor of the MWIR nBn detector performance at low (<150 K) temperatures.

[1]  Darryl L. Smith,et al.  Proposal for strained type II superlattice infrared detectors , 1987 .

[2]  G. Wicks,et al.  nBn detector, an infrared detector with reduced dark current and higher operating temperature , 2006 .

[3]  Elena Plis,et al.  Midwave infrared type-II InAs∕GaSb superlattice detectors with mixed interfaces , 2006 .

[4]  J. Ziegler,et al.  InAs/GaSb superlattice focal plane arrays for high-resolution thermal imaging , 2006 .

[5]  Sang Jun Lee,et al.  Electrochemical sulphur passivation of InAs/GaSb strain layer superlattice detectors , 2006 .

[6]  E. Plis,et al.  nBn based infrared detectors using type-II InAs/(In,Ga)Sb superlattices , 2008, SPIE Defense + Commercial Sensing.

[7]  Martin Walther,et al.  Passivation of InAs∕(GaIn)Sb short-period superlattice photodiodes with 10μm cutoff wavelength by epitaxial overgrowth with AlxGa1−xAsySb1−y , 2005 .

[8]  H. S. Kim,et al.  Type II InAs∕GaSb strain layer superlattice detectors with p-on-n polarity , 2007 .

[9]  Yajun Wei,et al.  Near bulk-limited R0A of long-wavelength infrared type-II InAs/GaSb superlattice photodiodes with polyimide surface passivation , 2007 .

[10]  Vishnu Gopal.  Variable-area diode data analysis of surface and bulk effects in HgCdTe photodetector arrays , 1994 .

[11]  Yajun Wei,et al.  Very high quantum efficiency in type-II InAs/GaSb superlattice photodiode with cutoff of 12 μm , 2007 .

[12]  Hooman Mohseni,et al.  Interface-induced suppression of the Auger recombination in type-II InAs/GaSb superlattices , 1998 .

[13]  Elena Plis,et al.  nBn detectors based on InAs∕GaSb type-II strain layer superlattice , 2008 .