The diffusion of Si was studied in [100] GaAs specimens which had been implanted with 40keV 30Si+ ions to a dose of 1016/cm2. The Si interstitials were identified by fitting a concentration-dependent diffusion model to Si depth profiles which had been measured by using secondary ion mass spectrometry. In addition to Si which was located on Ga and As sites, and SiGa+-SiAs- pairs, interstitial Si was also taken into account for the first time. The charge state of the Si interstitial was chosen to be +1, in order to fit the experimental profiles most closely.

Identification of Silicon Interstitials in Ion-Implanted GaAs T.Ahlgren: Physical Review Letters, 1998, 81[4], 842-5