Mid-wavelength infrared unipolar nBp superlattice photodetector
Abstract
We report a Mid-Wavelength Infrared (MWIR) barrier photodetector based on the InAs/GaSb/AlSb type-II superlattice (T2SL) material system. The nBp design consists of a single unipolar barrier (InAs/AlSb SL) placed between a 4 μm thick p-doped absorber (InAs/GaSb SL) and an n-type contact layer (InAs/GaSb SL). At 80 K, the device exhibited a 50% cut-off wavelength of 5 μm, was fully turned-ON at zero bias and the measured QE was 50% (front side illumination with no AR coating) at 4.5 μm with a dark current density of 4.7 × 10-6 A/cm2 at Vb = 50 mV. At 150 K and Vb = 50 mV, the 50% cut-off wavelength increased to 5.3 μm, and the QE was 54% at 4.5 μm with a dark current of 5.0 × 10-4 A/cm2.
- Publication:
-
Infrared Physics and Technology
- Pub Date:
- January 2018
- DOI:
- 10.1016/j.infrared.2017.11.008
- Bibcode:
- 2018InPhT..88..114K
- Keywords:
-
- MWIR detectors;
- Type-II strained layer superlattice;
- Barrier engineering;
- Dark current;
- Quantum efficiency