Disclosed herein is a method of recovering performance of a radiation detector, the radiation detector comprising: a radiation absorption layer configured to absorb radiation particles incident thereon and generate an electrical signal based on the radiation particles; an electronic system configured to process the electrical signal, the electronic system comprising a transistor, the transistor comprising a gate insulator with positive charge carriers accumulated therein due to exposure of the gate insulator to radiation; the method comprising: removing the positive charge carriers from the gate insulator by establishing an electric field across the gate insulator.