The importance of band alignment in VLWIR type-II InAs/GaSb heterodiodes containing the M-structure barrier

The Type-II InAs/GaSb superlattice photon detector is an attractive alternative to HgCdTe photodiodes and QWIPS. The use of p+ - π - M - N+ heterodiode allows for greater flexibility in enhancing the device performance. The utilization of the Empirical Tight Binding method gives the band structure of the InAs/GaSb superlattice and the new M- structure (InAs/GaSb/AlSb/GaSb) superlattice allowing for the band alignment between the binary superlattice and the M- superlattice to be determined and see how it affects the optical performance. Then by modifying the doping level of the M- superlattice an optimal level can be determined to achieve high detectivity, by simultaneously improving both photo-response and reducing dark current for devices with cutoffs greater than 14.5 μm.

[1]  Yajun Wei,et al.  Capacitance-voltage investigation of high-purity InAs∕GaSb superlattice photodiodes , 2006 .

[2]  Jeffrey H. Warner,et al.  Graded band gap for dark-current suppression in long-wave infrared W-structured type-II superlattice photodiodes , 2006 .

[3]  Manijeh Razeghi,et al.  Beryllium compensation doping of InAs∕GaSb infrared superlattice photodiodes , 2007 .

[4]  Gabby Sarusi,et al.  QWIP or other alternative for third generation infrared systems , 2003 .

[5]  Manijeh Razeghi,et al.  Substrate removal for high quantum efficiency back side illuminated type-II InAs∕GaSb photodetectors , 2007 .

[6]  Manijeh Razeghi,et al.  Background limited long wavelength infrared type-II InAs/GaSb superlattice photodiodes operating at 110 K , 2008 .

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

[8]  Majid Zandian,et al.  MBE HgCdTe Technology: A Very General Solution to IR Detection, Described by “Rule 07”, a Very Convenient Heuristic , 2008 .

[9]  Manijeh Razeghi,et al.  Very high performance LWIR and VLWIR Type-II InAs/GaSb superlattice photodiodes with M-structure barrier , 2008, Optical Engineering + Applications.

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

[11]  Manijeh Razeghi,et al.  Dark current suppression in type II InAs∕GaSb superlattice long wavelength infrared photodiodes with M-structure barrier , 2007 .

[12]  Jagmohan Bajaj,et al.  Comparison of type-II superlattice and HgCdTe infrared detector technologies , 2007, SPIE Defense + Commercial Sensing.

[13]  Antoni Rogalski,et al.  Material considerations for third generation infrared photon detectors , 2007 .

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