Impact of temperature and gamma radiation on electron diffusion length and mobility in p-type InAs/GaSb superlattices
Abstract
The minority carrier diffusion length was directly measured by the variable-temperature Electron Beam-Induced Current technique in InAs/GaSb type-II strain-layer-superlattice infrared-detector structures. The Molecular Beam Epitaxy-grown midwave infrared superlattices comprised 10 monolayers of InAs and 10 monolayers of GaSb to give a total absorber thickness of 4 μm. The diffusion length of minority electrons in the p-type absorber region of the p-type/barrier/n-type structure was found to increase from 1.08 to 2.24 μm with a thermal activation energy of 13.1 meV for temperatures ranging from 77 to 273 K. These lengths significantly exceed the individual 10-monolayer thicknesses of the InAs and GaSb, possibly indicating a low impact of interface scattering on the minority carrier diffusion length. The corresponding minority electron mobility varied from 48 to 65 cm2/V s. An absorbed gamma irradiation dose of 500 Gy halved the minority carrier diffusion length and increased the thermal activation energy to 18.6 meV, due to creation of radiation-induced defect recombination centers.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Jun 18, 2018
- Source ID
- 10.1063/1.5030444
Entities
People
- Alireza Kazemi
- Chris J. Fredricksen
- Elena Flitsiyan
- Jonathan Lee
- Leonid Chernyak
- Lilian K. Casias
- Robert E. Peale
- Sanjay Krishna
- Stephen Myers
- Zahra Taghipour
Organizations
- Air Force Research Laboratory
- Missile Defense Agency
- National Science Foundation
- Ohio State University
- University of Central Florida
- University of New Mexico