Study of PIN Junctions in GaAsSb Nanowires on Si for the Next Generation Infrared Photodetectors
Abstract
A comprehensive investigation of p-i-n (PIN) structured GaAsSb nanowire (NW) growths by molecular beam epitaxy and high performance near infrared-based photodetectors (PD) of axial and core-shell (CS) architectures are presented. GaAsSb NW exhibited space charge limited conduction mechanism. In-situ annealed NWs revealed significant reduction in the trap density from 1016 cm-3 in as-grown NWs to a low level of 7 * 1014 cm-3 and confining wider trap energy distribution to a narrow distribution of 0.12 eV. Te-doping assessment in NWs was successfully accomplished using GaTe captive source and surface analytical tools XPS/UPS and CAFM/SKPM. A Schottky barrier photodetector was demonstrated using Te-doped ensemble NWs with a broad spectral range and a longer wavelength cut-off at ~ 1.2 m. These photodetectors exhibited high responsivity in the range of 580 620 A/W and detectivity of 1.2 3.8 x 1012 Jones. Our study of ultrafast carrier transport and recombination dynamics in Te-doped GaAsSb shows a carrier recombination lifetime of 147 3 ps with a fast rise time of ~ 2ps. We also show that the ex-situ atomic layer deposited Al2O3 layer is not an effective GaAsSb NW passivator.
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 03, 2023
- Accession Number
- AD1223754
Entities
Organizations
- North Carolina Agricultural and Technical State University