Abstract
Electrical activation studies of Siβimplanted Al~x~ Ga~1βx~ N (x = 0.1 and 0.18) grown on sapphire substrate have been made as a function of anneal time, anneal temperature, and ion dose. Silicon implantation was done at room temperature with a dose ranging from 5 Γ 10^13^ to 5 Γ 10^15^ cm^β2^ at 200 keV. The samples were proximity cap annealed from 1100 to 1250 Β°C for 5β40 min with a 500 Γ
βthick AlN cap in a nitrogen environment. The electrical activation efficiencies of 84% and 75% were obtained for the Al~0.1~Ga~0.9~N after annealing at 1200 Β°C for 40 min for a dose of 5 Γ 10^13^ and 1 Γ 10^14^ cm^β2^, respectively. For the Al~0.18~Ga~0.82~N, nearly 100% activation for a dose of 5 Γ 10^14^ cm^β2^ and 94% for a dose of 1 Γ 10^15^ cm^β2^ were achieved after annealing at 1250 Β°C and 1200 Β°C for 20 min, respectively. Both the activation efficiency and mobility increase with anneal time and anneal temperature, indicating an improved implantation damage recovery. The highest mobility obtained at room temperature is 89 cm^2^/Vs for the Al~0.1~Ga~0.9~N samples having doses of 5 Γ 10^13^ and 1 Γ 10^14^ cm^β2^ and annealed at either 1200 Β°C for 40 min or 1250 Β°C for 20 min. (Β© 2006 WILEYβVCH Verlag GmbH & Co. KGaA, Weinheim)