Electron-damage studies in GaP at low temperature

The defects introduced in p-type Zn doped GaP by beta particle irradiation, of 1 MeV average energy, at low temperatures are monitored by bridge measurements of capacitance and delectric losses of a capacitor. The results of measurements, between 15 and 65 K, are attributed, in two different temperature regimes, to a GaP capacitor with losses arising from (a) an a.c hopping conduction process, below 45 K, and (b) a band conduction, above 45 K. Electron irradiation affects both hopping and band conduction as well as the transition temperature.