The electrical properties of the interface between Hg_0.8Cd_0.2Te (MCT) and its oxide film prepared by anodic oxidation were estimated at 77 K. The surface charge states density Q_ss, fast surface states density Nss, type of states of passivity anodic oxide films are obtained from capacitance-voltage measurement. The interface between MCT and its anodic oxide film is characterized by a fast surface states density of the order of N_ss = 7 × 10¹⁰ eV^-1 cm^-2 near the middle of the bandgap and of N_ss = 7 × 10¹¹ eV^-1 cm^-2 at flat band voltage in accordance with fixed surface charge states density Q_ss = 2 × 10^-8 C cm^-2 (for n-type samples). The fixed oxide surface charge states density is positive for both p-type and n-type MCT semiconductors. © 1998 Elsevier Science S.A. All rights reserved.

Ngoc N.T.B., Nha N.V.

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Từ khóa : Anodic oxidation; Capacitance measurement; Energy gap; Film preparation; Mercury compounds; Voltage measurement; Mercury cadmium telluride; Passivity anodic oxide; Surface potential; Semiconducting films