ELECTRON SUBBAND STRUCTURE OF HGCDTE METAL-INSULATOR-SEMICONDUCTOR HETEROSTRUCTURES

The doping and pressure dependence of the surface layer capacitance has been investigated in this work for Hg0.8 Cd0.2 Te with doping concentration N(A) from 3.6 x 10(16) to 1.1 x 10(18) cm-3 and under hydrostatic pressure up to 7.3 kbar at temperature 4.2 K. By using a capacitance-voltage spectroscopy (C-V) fitting model, the subband structures such as the first subband energy E0 as a function of the energy gap E(g) and the variation of E0 with doping have been determined. The second onset of the inversion in capacitance spectroscopy on HgCdTe MIS structure has been observed. By using an expanded C-V fitting model several quantum parameters relating to the second subband of inversion layer electron can be determined quantitatively.