PROPERTY OF RADIATION-INDUCED DEFECTS IN GERMANIUM SINGLE-CRYSTALS

To study the property of defects produced in high-purity and p-type germanium single crystals by thermal neutron, fast neutron or electron irradiation, annealing experiments on irradiated samples were performed with electrical measurements and a deep-level transient spectroscopy technique. The annealing behavior of defects produced by the recoil energy of (n, gamma) reaction in a high-purity sample irradiated with thermal neutrons indicates that interstitial arsenic atoms and interstitial gallium atoms are restored to lattice sites during annealing in the temperature range from 180 degrees C to 240 degrees C and that from 260 degrees C to 340 degrees C, respectively. The defects produced by neutron irradiation were annihilated by annealing for 20 min at 380 degrees C. Two hole traps located at E(v) +/- 0.32 eV and E(v) +/- 0.53 eV were formed in a high-purity crystal by electron irradiation.