Random telegraph signals in a radiation-hardened CMOS active pixel sensor

The random telegraph signal (RTS) behavior of the dark current has been studied in a radiation-hardened CMOS active pixel sensor (APS). Several devices have been irradiated with protons of different energies and up to different fluences. The influence of the proton energy, fluence, and operating temperature on the amplitude, time constants, and occurrence of the RTS is investigated. Mechanisms for this behavior are discussed and several suggestions are made for possible defect types.