Title :
Uncooled InAs-GaSb type-II infrared detectors grown on GaAs substrates for the 8-12-μm atmospheric window
Author :
Mohseni, H. ; Wojkowski, J. ; Razeghi, M. ; Brown, G. ; Mitchel, W.
Author_Institution :
Centre for Quantum Devices, Northwestern Univ., Evanston, IL, USA
fDate :
7/1/1999 12:00:00 AM
Abstract :
We report on the growth and characterization of type-II infrared detectors with an InAs-GaSb superlattice active layer for the 8-12-μm atmospheric window at 300 K. The material was grown by molecular beam epitaxy on semi-insulating GaAs substrates. Photoconductive detectors fabricated from the superlattices showed 80% cutoff at about 12 μm at room temperature. The responsivity of the device is about 2 mA/W with a 1-V bias (E=5 V/cm) and the maximum measured detectivity of the device is 1.3×108 cm.Hz1/2/W at 11 μm at room temperature. The detector shows very weak temperature sensitivity. Also, the extracted effective carrier lifetime, τ=26 ns, is an order of magnitude longer than the carrier lifetime in HgCdTe with similar bandgap and carrier concentration
Keywords :
III-V semiconductors; carrier density; carrier lifetime; gallium compounds; indium compounds; infrared detectors; photoconducting devices; semiconductor superlattices; sensitivity; 1 V; 11 mum; 300 K; 8 to 12 mum; GaAs; GaAs substrates; IR atmospheric window; InAs-GaSb; InAs-GaSb superlattice active layer; bandgap; carrier concentration; extracted effective carrier lifetime; infrared detectors; maximum measured detectivity; molecular beam epitaxy; photoconductive detectors; responsivity; room temperature; semi-insulating GaAs substrates; uncooled InAs-GaSb type-II IR detectors; weak temperature sensitivity; Charge carrier lifetime; Gallium arsenide; Infrared detectors; Molecular beam epitaxial growth; Photoconducting materials; Photoconductivity; Photonic band gap; Substrates; Superlattices; Temperature sensors;
Journal_Title :
Quantum Electronics, IEEE Journal of
