ANNEALING PROPERTIES OF DEFECTS IN ION-IMPLANTED 3C-SIC STUDIED USINGMONOENERGETIC POSITRON BEAMS

Annealing properties of defects in N-2+- or Al+-implanted 3C-SiC were studied using monoenergetic positron beams. For as-implanted specimens , the mean size of the open volume of defects was estimated to be clos e to that of divacancies. Based on the annealing behavior of the chara cteristic value of the S parameter corresponding to the annihilation o f positrons trapped by vacancy-type defects, the temperature range for the annealing of defects was divided into five stages, and they were arbitrarily designated as I-V. Annealing behavior in stages I (20-500 degrees C), II (500-800 degrees C) and III (800-1000 degrees C) was id entified as the agglomeration of vacancy-type defects due to migration s of carbon vacancies. Si vacancies and vacancy complexes such as diva cancies, respectively. Stages IV (1000-1200 degrees C) and V (1200-140 0 degrees C) were assigned to be the formation of extended defects and their recovery processes, respectively. Effects of the species of the implanted ions and the substrate temperature during ion implantation on annealing properties of defects are also discussed.