Relationship between high resistivity and the deep level defects in CZT:In

► We explain the high resistivity performance for a CZT:In crystal. ► Fermi level is pinned near the mid-gap of SI-CZT:In. ► Deep donor level EDD can stabilize the Fermi level deep near the mid-gap. ► Origin of EDD level is assigned to TeCd2+ below the conduction band.