Investigation of the ZnS-CdHgTe interface

The ZnS-CdxHg1−xTe interface was investigated using the capacitance-voltage characteristics of MIS structures in experimental samples. During fabrication of the n+-p junctions based on p-CdxHg1−xTe, the density of states within the range N ss =(1–6)×1011 cm−2 eV−1 at T=78 K was obtained. The experiments showed that the conditions in which n+-p junctions are fabricated only slightly affect the state of the ZnS-CdHgTe interface. The negative voltages of the at bands V FB , even if immediately after deposition of the ZnS films V FB >0, point to the enrichment of the ZnS-p-CdHgTe near-surface layer with majority carriers, specifically, holes. This led to a decrease in the leakage current over the surface. During long-term storage (as long as ∼15 years) in air at room temperature, no degradation of differential resistance R d , current sensitivity S i , and detectivity D* of such n+-p junctions with a ZnS protection film was observed.