Understanding defects in type-II superlattice IR photodiodes

This paper studies T2SL material properties using chemical and structural probes with atomic scale resolution, and transport tools that are particularly sensitive to SRH centers, defect scattering, and surface leakage. Electron beam induced current (EBIC) mapping is being used to identify individual localized recombination centers, which are then probed compositionally with energy dispersive x-ray spectroscopy (EDS). Focused ion beam milling (FIB) is used to extract regions of high recombination that neighbor inactive regions for high resolution transmission electron microscopy, to fully reveal and compare their underlying structure.