Physics Chat
MOCVD growth of Sb-based Type-II superlattices for IR detectors from 4-10 um
Speaker: Richard Brown (Dr Qiang Li' group)
Date: Thursday 30 November 2023
Time: 14:00
Venue: TRH Seminar Room 0.01
Mid-wave and long-wave Infrared devices play an important role in cutting edge applications including gas detection, biomedical sensing, thermal imaging and Light Detection and Ranging (LIDAR). Antimony (Sb) based type-II superlattice (T2SL) materials are a strong candidate for next generation infrared technologies due to advantageous manufacturability and flexible band engineering, when compared to the classically used mercury cadmium telluride. Traditionally, T2SLs are predominately developed via MBE on lattice-matched GaSb substrates. This work however, focuses on transferring the growth from MBE to MOCVD, in order to reduce cost and increase the commercial viability of the T2SL for the wide range of IR applications available. In this talk, I will present our recent progress in growing both Ga-free and Ga-containing T2SLs. I will discuss how to optimise growth parameters and engineer interfacial layers to achieve strain balanced superlattices that are perfectly lattice matched to the growth substrate. Device opportunities including fabricating PIN and nBn photodetectors will also be presented.