@article{oai:nitech.repo.nii.ac.jp:00005091, author = {Nakano, Yoshitaka and Jimbo, Takashi}, issue = {7}, journal = {JOURNAL OF APPLIED PHYSICS}, month = {Oct}, note = {Si-doping characteristics have been systematically investigated for Si+N co-implanted GaN. n-type regions were produced in undoped GaN films by the co-implantation and subsequent annealing with an SiO2 encapsulation layer at high temperatures. The sheet carrier concentration is seen to be precisely controllable between 3×1012 and 5×1014 cm-2 with Si activation efficiencies of ?50% when the samples were annealed at 1300°C. From atomic force microscopic observations, the co-implanted sample shows smooth surface morphology identical to that before implantation, whereas Ga islands are found to be formed in the surface region by the activation annealing in the case of conventional Si implantation. Therefore, the Si+N co-implantation technique turns out to be an effective method to enhance electrical and structural properties in view of GaN stoichiometry. However, implantation-induced microdefects seem to remain even after the high-temperature annealing process for both Si- and Si+N-implanted GaN samples., application/pdf}, pages = {3815--3819}, title = {Co-implantation of Si+N into GaN for n-type doping}, volume = {92}, year = {2002} }