MODIFICATION OF HGCDTE-NATIVE OXIDE INTERFACE BY ANNEALING

The interface properties of Hg1-xCdxTe (MCT) with native oxide (NO) af ter annealing at various stages of MIS device (Me-Si3N4-SiO2-NO-MCT (p -type)) fabrication have been investigated. Heat treatments were provi ded in vacuum and in the atmosphere at temperatures of 100 to 130 degr ees C before and after native oxide formation and after deposition of SiO2 overcoated with Si3N4. The fixed charge value in the oxide varied from -2.5 x 10(11) cm(-2) to +5 x 1011 cm(-2) in dependence on the an nealing conditions. At the same time the amount of interface traps and near-surface band-gap states changed. It is assumed that these change s are caused by mercury migration at heating. The vacuum annealing of the oxidized samples before deposition of the dielectric layers signif icantly improves the MCT-insulator interface properties.