He-induced cavity formation in silicon upon high-temperature implantation

40 keV He+ ions were implanted into (1 0 0) oriented Si single crystals to a fluence of 9x1015 cm-2 at room-temperature or 350 deg. C. The implantations were performed at both, random or <0 0 1> Si channel directions. The implantation damage and the in situ annealing effects during the He implantations were investigated by transmission electron microscopy (TEM), Rutherford backscattering/channeling spectrometry (RBS/C) and elastic recoil detection analysis (ERDA). Significant differences in the microstructure evolution between the 350 deg. C and the room-temperature implanted and subsequently annealed at 350 deg. C samples were observed. The results are discussed in terms of a distinct He bubble nucleation process