A Positron lifetime investigation of InP electron irradiated at 100 K

Positron lifetime investigations have been made on variously doped InP samples irradiated at 100 K with 2.5 MeV electrons. Three irradiation-produced positron lifetimes were found: 240+/-10, 265 +/- 10, and 330+/-20 ps which an, respectively, ascribed to V-p, V-In, and V-p . V-In vacancies in close association with interstitials. Total introduction rates of these defects were in the range of 0.6-1.2 cm(-1). Observation of the defects depends on the position of the Fermi level, In n-type materials no evidence could be found for V-p . P-I, while in p-type material V-In.-In-I was not observed. Annealing studies up to 300 K show that V-p . P-I, anneals slightly below 300 K, while V-In. In-I anneals in part around 125 Kt but a sizable fraction remains at 300 K. Divacancies begin annealing at 125 K, but some call persist to 300 K. (C) 1996 American Institute of Physics.