Direct growth of InAs/GaSb type II superlattice photodiodes on silicon substrates

Abstract

In this study, p-i-n InAs/GaSb type II superlattice photodiodes were directly grown on silicon substrates. The superlattice structures were grown monolithically on miscut Si substrates via a 10 nm AlSb nucleation layer. Interfacial misfit array technique was used to accommodate the large lattice mismatch between III-Sb epi-layers and Si. Atomic force microscopy and X-ray diffraction measurements revealed degraded material quality of type II superlattices grown on Si, compared with the sample grown on GaAs. Photoluminescence characterisation indicates comparable optical properties with about 39% deduction of peak intensity. Dark current measurements were also used to study the electrical properties of the samples.