Extended wavelength dilute-bismide infrared nBn photodetectors on InSb
Abstract
Bismuth incorporation into InSb has the potential to fill a significant technological gap for narrow bandgap III-V alloys that can be grown directly on commercially available substrates with tunable long-wave infrared bandgap energies for sensing applications. Here, we demonstrate the first InSbBi photodetector with a unipolar barrier grown directly on InSb substrates. With only 1% bismuth incorporation, the InSbBi photodetector demonstrated a significant extension in cutoff wavelength of >1 μm beyond that of a nominally identical InSb detector at 79 K. A peak external quantum efficiency of 6% was measured for the InSbBi detector. Pathways to high-performance InSb-based dilute-bismide detectors are presented via (1) quaternary dilute-bismide absorbers and barriers with minimal strain and optimized band alignments or (2) enhanced absorption in detectors with ultra-thin absorbers via refractive index engineering. The work presented highlights the potential of InSbBi nBn detectors as an alternative emerging candidate for long-wave infrared photodetection.
Article Details
Journal Info
Applied Physics Letters
American Institute of Physics
Authors (6)
R. C. White
M. K. Bergthold
Microelectronics Research Center and the Electrical and Computer Engineering Department, The University of Texas at Austin , Austin, Texas 78758,
F. A. Estévez H
Microelectronics Research Center and the Electrical and Computer Engineering Department, The University of Texas at Austin , Austin, Texas 78758,
A. F. Ricks
Microelectronics Research Center and the Electrical and Computer Engineering Department, The University of Texas at Austin , Austin, Texas 78758,
D. Wasserman
S. R. Bank