Defects in 140keV B+-implanted (p-type) Hg0.78Cd0.22Te were studied by measuring Doppler broadening profiles as a function of the incident positron energy. In non-implanted specimens, the major defect species was the Hg vacancy, VHg; with an estimated concentration of 6 x 1015/cm3. In these B+-implanted specimen, the damaged regions had an n-type nature, and vacancy-type defects were present in the region. Below the n-type layer, about 50% of the VHg were annihilated via recombination between VHg and Hg atoms. The mean size of the open spaces of vacancy-type defects in the n-type layer decreased after annealing at 150C. The electron concentration in the n-type layer also decreased at the same temperature. Thus, the origin of donors was attributed to interstitial-type defects or their clusters. The annealing temperature of the vacancy-type defects which were introduced by ion implantation was found to be 300C.

A.Uedono, H.Ebe, M.Tanaka, S.Tanigawa, K.Yamamoto, Y.Miyamoto: Japanese Journal of Applied Physics - 1, 1998, 37[3A], 786-91