Silicon implantation into GaAs: Observations of dose rate dependent electrical activation and damage

The electrical activation of ion-implanted silicon in GaAs has been studied as a function of dose rate (i.e., ion-current density). For a fluence of 1014 cm−2, the Hall sheet carrier activation is shown to depend strongly on the dose rate at which the implant was carried out. Carrier concentrations of 7×1018 cm−3 were produced at a 50×10−9 A/cm2 ion-current density. The variation in electrical activation is believed to be the result of a dose rate dependence of the ion-induced damage of GaAs which can be clearly seen in Rutherford backscattering (RBS) channeling measurements of 1015 cm−2 implants.