Hier finden Sie wissenschaftliche Publikationen aus den Fraunhofer-Instituten.

InAs/GaSb superlattice detectors for the long-wavelength infrared regime

: Rehm, R.; Masur, J.-M.; Schmitz, J.; Walther, M.


Andresen, B.F. (Ed.) ; Society of Photo-Optical Instrumentation Engineers -SPIE-, Bellingham/Wash.:
Infrared technology and applications XL : 5–8 May 2014, Baltimore, Maryland, United States
Bellingham, WA: SPIE, 2014 (Proceedings of SPIE 9070)
ISBN: 978-1-6284-1007-5
Paper 90700T, 7 S.
Conference "Infrared Technology and Applications"<40, 2014, Baltimore/Md.>
Fraunhofer IAF ()
Type-II InAs/GaSb superlattice; LWIR; generation-recombination dark current suppression; heterojunction

To enable higher operating temperatures in InAs/GaSb superlattice detectors for the long-wavelength infrared atmospheric window at 8-12 µm, a reduction of the bulk dark current density is indispensable. To reduce the dark current of conventional homojunction pin-diode device designs, bandstructure-engineering of the active region is considered most promising. So far, several successful device concepts have been demonstrated, yet they all rely on the inclusion of Aluminum within the active layers. Driven by manufacturing aspects we propose an Al-free heterojunction device concept that is based on a p(+)-doped InAs/GaSb superlattice absorber layer combined with an adjacent N(-)-doped high gap region, which again is realized with an InAs/GaSb superlattice. To calculate the superlattice band gap and the position of the conduction band edge at the heterojunction we employ the Superlattice Empirical Pseudopotential Method. With a series of three heterojunction p(+)N(-) InAs/GaSb superlattice devices with an absorber band gap of 124 meV (10.0 µm) we give a first proof of the advocated device concept.