Charge transport and trapping in HgCdTe MIS devices

A pulsed UV (ultraviolet) excitation technique was used to study the bias- and photon-energy dependences of charge transport and trapping processes in HgCdTe MIS devices containing a ZnS/anodic-sulfide dual-dielectric gate insulator. Electron and hole transport in the insulator occurs rapidly (<1 ms) at 84 K. The dependences of UV-induced flatband voltage shift on bias and on the number of incident photons (equivalent to total dose) are similar to results of Co-60 irradiations. The centroids of the electron and hole trap distributions were determined to be near the ZnS/anodic-sulfide interface and near the center of the dual-dielectric insulator, respectively