Rapid thermal annealing of Mg++As+ dual implants in GaAs

Mg+ and As+ ions were implanted into GaAs to study the effects of dual implantation on the electrical properties. Increased electrical activity and significantly less redistribution of the magnesium were observed for the dual implants compared with the single implants. A maximum activity of 40% with a sheet resistivity as low as 185 Ω/⧠ was obtained for the dual implant compared to an activity of 27% with a resistivity of 250 Ω/⧠ for the single implant at a dose of 1015 cm−2. A peak hole concentration approaching 4×1019 cm−3 was recorded for the dual implant annealed at 900 °C for 30 s.