Direct minority carrier transport characterization of InAs/InAsSb superlattice nBn photodetectors

• Published in: Applied physics letters Vol. 106; no. 7
• Main Authors: Zuo, Daniel, Liu, Runyu, Wasserman, Daniel, Mabon, James, He, Zhao-Yu, Liu, Shi, Zhang, Yong-Hang, Kadlec, Emil A., Olson, Benjamin V., Shaner, Eric A.
• Format: Journal Article
• Language: English
• Published: United States 16-02-2015
• Subjects: ANTIMONIDES; CARRIER LIFETIME; CHARGE CARRIERS; CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; DEPLETION LAYER; DIFFUSION LENGTH; ELECTRIC CURRENTS; INDIUM ARSENIDES; INTERFACES; NIOBIUM NITRIDES; PHOTODETECTORS; PHOTOLUMINESCENCE; SCANNING ELECTRON MICROSCOPY; SUPERLATTICES; TIME RESOLUTION
• ISSN: 0003-6951; 1077-3118

We present an extensive characterization of the minority carrier transport properties in an nBn mid-wave infrared detector incorporating a Ga-free InAs/InAsSb type-II superlattice as the absorbing region. Using a modified electron beam induced current technique in conjunction with time-resolved photoluminescence, we were able to determine several important transport parameters of the absorber region in the device, which uses a barrier layer to reduce dark current. For a device at liquid He temperatures, we report a minority carrier diffusion length of 750 nm and a minority carrier lifetime of 200 ns, with a vertical diffusivity of 3 × 10{sup −2} cm{sup 2}/s. We also report on the device's optical response characteristics at 78 K.