Defects in Ion Implanted Hg_0.78Cd_0.22Te Probed by Monoenergetic Positron Beams

Defects and their annealing properties in ion implanted Hg_0.78Cd_0.22Te were studied using monoenergetic positron beams. Vacancy-type defects introduced by B⁺-implantation were identified as open spaces associated with extended defects such as dislocation loops and stacking faults. For an Ar⁺-implanted specimen, the mean size of the open volume of defects in the damaged region was estimated to be that of divacancies. The observed difference between the species of defects in the B⁺- and the Ar⁺-implanted specimens was attributed to the suppression of the recombination between vacancies and interstitials in the damaged region introduced by Ar⁺-implantation. The annealing temperature of the vacancy-type defects introduced by Ar⁺-implantation was determined to be 300°C.