Abstract

We report on characterization, performance and applications of nuclear detectors fabricated on Semi-Insulating (SI) Liquid Encapsulated Czokralski (LEC) grown GaAs. We have developed a non alloyed and non injecting ohmic contact (NAOC) based on ion implantation to fabricate detectors which can operate at applied voltages greater than the one needed to make them fully depleted. With such a detectors and at high applied voltages, Va > 500 V, a nearly full charge collection efficiency has been achieved for both alpha particles and X-rays. Furthermore the best energy resolution achieved at room temperature has been 1.1% for 5.48 MeV alpha particles and 26.1% for 59.5 keV X-rays, while at -30 °C the best energy resolution measured for X-rays has been 4.1%.