Study of the characteristics of electrical and optical response of gan sensors

Study of the Characteristics of Electrical and Optical Response of GaN Sensors In this work, sensors fabricated of the ammono-thermal (AT) GaN doped with Mg and Mn have been studied in case to reveal GaN detectors response dependence on neutron fluences. Excess carrier lifetime is one of the most important material parameters which is directly related with material defects. Therefore, carrier lifetime ascribed to radiative and non-radiative recombination has been examined by combining time-resolved luminescence and microwave probed photo-conductivity transient techniques, respectively. The charge collection efficiency (CCE) has been examined by surface and edge profiling of carrier drift transients by using transient current pulsed technique. These profiles were compared for the pristine and neutron irradiated sensors. A decrease of CCE to ~2% was obtained for samples irradiated with the highest fluence of reactor neutrons. Also, it has been revealed that sensor response is governed by carrier lifetime decrease in the irradiated sensors, while carrier drift component is observable only in sensors made of the pristine AT GaN material