Novel Passivation Approach of InAs/GaSb Superlattice for Mid-Short Wavelength Dual-Color Infrared Detector

Abstract

For higher surface state density of InAs/GaSb type II superlattice materials, it is easy to form conductive oxide layer on the material surface. The first problem to be solved is passivation in the process of preparing infrared devices with InAs/GaSb superlattice materials. Passivation effect and coating quality have great influence on the surface leakage and noise of infrared devices. The method of zinc sulfide coating after anodic fluorination was used to passivate the mid-short wavelength dual-color InAs/GaSb superlattice. The reliability of anodic fluorination is confirmed by Auger electron spectroscopy. The J-V test results at 77 K are used to verify the passivation effect of fluorination and the improvement effect of leakage current density. The results show that the passivation method of zinc sulfide coating after anodic fluorination can effectively suppress the leakage current.

Keywords

• |inas/gasb superlattice|mbe|passivation|dual-color infrared detector|anodic fluorination