Annealing Properties of Defects in B⁺- and F⁺-Implanted Si Studied Using Monoenergetic Positron Beams

Annealing properties of defects in F⁺- and B⁺-implanted Si were studied using monoenergetic positron beams. For F⁺-implanted specimen with a dose of 2×10¹³ F/cm², before annealing treatment, the mean size of the open volume of defects was estimated to be close to the size of divacancies. After rapid thermal annealing (RTA) at 700° C, vacancy-fluorine complexes and vacancy clusters were formed. The mean size of the open volume for the vacancy-fluorine complexes was estimated to be close to the size of monovacancies, and their annealing temperature was determined to be 800° C. For F⁺-implanted specimen with a dose of 4×10¹⁵ F/cm², complexes between vacancy clusters and fluorine atoms were introduced during solid-phase epitaxial growth of the amorphous region, and they were observed even after RTA at 1100° C. Effects of additional B⁺ implantation on annealing properties of defects are also discussed.