HIGH ACTIVATION EFFICIENCY IN MG+ IMPLANTED GAAS BY P+ COIMPLANTATION

Coimplantation of 125 keV Mg+ ions and 160 keV P+ ions with the same dose of 5×1014 cm−2 was investigated. Samples were annealed in a conventional furnace or a halogen tungsten lamp rapid thermal annealing system. It was found that the additional implant of P+ improves the electrical quality of the Mg+ implanted GaAs more effectively than additional implant of As+. By using rapid thermal annealing, a maximum activation efficiency of 92% with a sheet resistance of 145 Ω/⧠ was obtained for Mg+ and P+ coimplantation after an anneal at 1050 °C for 5 s, while the maximum activation efficiency for Mg+ single implant was 36% corresponding to a sheet resistance of 358 Ω/⧠ after an anneal at 800 °C for 5 s. Coimplantation of P+ evidently can also reduce the redistribution of the implanted Mg.Coimplantation of 125 keV Mg+ ions and 160 keV P+ ions with the same dose of 5×1014 cm−2 was investigated. Samples were annealed in a conventional furnace or a halogen tungsten lamp rapid thermal annealing system. It was found that the additional implant of P+ improves the electrical quality of the Mg+ implanted GaAs more effectively than additional implant of As+. By using rapid thermal annealing, a maximum activation efficiency of 92% with a sheet resistance of 145 Ω/⧠ was obtained for Mg+ and P+ coimplantation after an anneal at 1050 °C for 5 s, while the maximum activation efficiency for Mg+ single implant was 36% corresponding to a sheet resistance of 358 Ω/⧠ after an anneal at 800 °C for 5 s. Coimplantation of P+ evidently can also reduce the redistribution of the implanted Mg.