Status of multi-wafer production MBE capabilities for extended SWIR III-V epi materials for IR detection

The authors report two approaches, the first based on growth of lattice matched InGaAs/GaAsSb superlattice on InP substrate with tunable bandgap in the 2 to 3 mu m range. The second approach is based on bulk random alloy InGaAsSb, which is tunable from 1.7 mu m to 4.5 mu m and lattice matched to the GaSb lattice constant. In each case, detector structures were fabricated and characterised. The authors have assessed the performance of these materials relative to commercially available extended short wave infrared devices through comparison to IGA-Rule 17 dark current performance level. A complementary barrier structure used in the InGaAsSb design showed improved quantum efficiency. The materials compare favourably to commercial technology and present additional options to address the challenging extended short wave infrared spectral band.