9732865 Pearton This project will investigate n- and p-type doping of GaN and related alloys by ion implantation and high temperature annealing to achieve greater understanding of doping in GaN and related materials. Research activities include study of several major topics: (i) use of Mg/O or Be/O co-implantation to achieve high (>10E18cm-3) p-type doping of GaN and AlGaN. By varying the doses of each co-implanted species existing theory will be tested, and the role of O established by comparing its effect to that of other species; co-implant species include N, Ar or F. (ii) comparison of different acceptor dopants: Ca was found to have a similar ionization level to that of Mg, i.e., ~170meV. Zn, Cd, Be will be implanted, and C, Ge and Sn will be co- implanted with group III species to assess their functionality as acceptors. (iii) comparison of different donor dopants; the doping properties of the group VI species, S, Se and Te are, as yet, not established in GaN. (iv) use of ultra-high annealing temperatures to achieve higher activation efficiency. Preliminary data indicate higher doping can be achieved for annealing at >1500 C. The major problem at these temperatures is preservation of the GaN surfaces - various methods of AlN deposition will be investigated as a solution. (v) investigation of new implant isolation species, such as V, Fe or Co, which might create thermally stable deep levels in GaN and have application to produce device isolation. The significance of this work will be the development of a more complete understanding of doping in GaN and related materials providing a materials science basis for selective area implantation in the development of advanced devices. %%% The project addresses basic research issues in a topical area of materials science having high technological relevance. The research will contribute basic materials science knowledge at a fundamental level to important aspects of electronic/photonic devices. The basic knowled ge and understanding gained from the research is expected to contribute to improving the performance and stability of advanced devices and circuits by providing a fundamental understanding and a basis for designing and producing improved materials, and materials combinations. An important feature of the program is the integration of research and education through the training of students in a fundamentally and technologically significant area. ***
