This project addresses ohmic contacts to the group III nitride semiconductor alloys. In particular, compositional shifts in semiconductor alloys when contacts are annealed will be investigated. This follows recent observations of enrichment of Al in Alx Ga1-x N and preferential incorpora-tion of Ga in annealed Ni, Pd and Au contacts. The influence of the type of metal (late versus early transition metal) and composition of the semiconductor alloy (Alx Ga1-x N, Inx Al1-x N or Inx Ga1-x N) will be studied in order to develop a thermodynamic and kinetic framework to de-scribe the phenomenon. The effect of a compositional shift in the semiconductor alloy on the electrical properties of the contacts will also be evaluated. Materials characterization efforts will rely primarily on transmission electron microscopy, x-ray photoelectron spectroscopy and scan-ning Auger microscopy, while electrical characterization will include current-voltage, capaci-tance-voltage, and ohmic contact resistance measurements. %%% The project addresses fundamental research issues associated with electronic/photonic materials having technological relevance. Basic advances in electrical contacts to the group III nitride semiconductor alloys will benefit efforts to develop solid state emitters for energy-efficient light-ing, and transistors that operate at high power and high frequencies for mobile communications. The project also creates an opportunity for the training of a graduate student and one or more un-dergraduate students. Additionally, the principal investigator will incorporate aspects of her re-search program into her classroom instruction. Her outreach activities-Summer Research Opportunities Program for minority students; Women in Science and Engineering Research; Nittany Camp (Science Camp for 6th and 7th grade Girls) promote science beyond the traditional walls of the unversity. ***
