A study was made of the effect of 100keV He+ implantation, and subsequent thermal annealing, upon the Raman scattering spectra of liquid encapsulated Czochralski single crystals with (100) and (111) orientations of the surface. An improvement in crystalline perfection was observed after He+ implantation to a dose of 1015/cm2, followed by annealing at 600 to 700C. The implantation-induced removal of thermally stable defect clusters which were related to the growth process was supposed to be largely responsible for the observed phenomena.

I.M.Tiginyanu, A.I.Terletsky, V.V.Ursaki: Solid State Communications, 1995, 96[10], 789-92