Radiation Induced Leakage Currents in Silicon on Sapphire MOS Transistors

Measurements are reported in which photodepopulation and thermal bleaching techniques have been applied to the study of radiation induced trapped positive charge in the Al2O3 substrate of n-channel MOS/SOS devices. Photodepopulation data indicates an optical depth for the hole traps of 2.5 eV. Thermal bleaching studies yield a corresponding thermal depth of 0.75 eV. Some preliminary thermally stimulated current measurements which reveal additional low temperature stable traps are also reported.