Electroreflectance study of HgCdTe in the metal-insulator-semiconductor configuration at 77 K

Abstract

Electroreflectance from Hg1−xCdxTe in the metal-insulator-semiconductor configuration at 77 K as a function of gate voltage has been investigated. We find the spectra consist of contributions from two considerably different compositions, one of which corresponds to semimetallic material (x≊0.1). The x≊0.1 component is a consequence of the passivation of the HgCdTe surface. There is some evidence that these two regions are distributed across the surface rather than in depth. In addition, the two components have different responses to the gate voltage. The higher composition region can be driven through a flat band while the lower composition portion cannot.