Estimation of Damage Induced by Focused Ga Ion Beam Irradiation

Abstract
We have measured the ballistic length l bFIB of a GaAs/AlGaAs sample using the electron focusing effect and the mean free path l eFIB of the narrow channel, both formed by focused ion beam (FIB) irradiation, to estimate the damage induced by FIB irradiation. It is observed that scattering centers are induced by FIB irradiation, which exhibit dependence on the electron density, unlike scattering centers due to grown-in defects. The FIB-induced scattering centers distribute far beyond the distance of the FIB spot size. This may be due to the exponential tail distribution of FIB.