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

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 theSparameter 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.