Investigation of Vacancy-Type Defects in P+-Implanted 6H-SiC Using Monoenergetic Positron Beams

Abstract

Vacancy-type defects and their annealing properties for 200 keV P+-implanted 6H-SiC were studied using monoenergetic positron beams. For the specimen with a dose of 1×1013/cm2, the mean size of the open volume of defects was estimated to be close to that of divacancies. Based on the annealing behavior of the S parameter corresponding to the annihilation of positrons trapped by vacancy-type defects, the temperature range for the annealing of vacancy-type defects was divided into three stages. Annealing behavior in stages I (200–700°C) and II (700–1000°C) was identified as the agglomeration of defects due to migrations of monovacancies and vacancy complexes such as divacancies, respectively. In stage II, near the defect-free region, the agglomeration of defects was suppressed by recombination of vacancy-type defects and interstitials. Stage III (1000–1300°C) was assigned to be the formation of extended defects and their recovery processes. The annealing behavior of the amorphous region introduced by ion implantation was also discussed.