9522082 Lau The purpose of this project is to investigate novel nitrogen sources for Group-III nitride growth by organometallic vapor phase epitaxy (OMVPE). Emphasis will be on the identification of (a) viable source(s) which will allow high quality nitride growth at lower temperatures than what are required using ammonia. A close collaborative effort has been established between the University of Massachusetts/Amherst and Morton Advanced Materials (a division of Morton International, Inc.), a major supplier of metalorganic sources of OMVPE. With sources developed by Morton, GaN will be grown with various growth parameters. Promising sources will be identified and thoroughly investigated via optimization growth experiments. Grown layers are characterized by microscopic, structural (double crystal X-ray diffraction and TEM), electrical (CV and Hall), and optical (transmission, photoluminescence) measurements. Feedback of growth results to Morton allows further refinement of the sources. Suitable p- and n-type dopant source compatible with the new nitrogen sources will also be identified through doping experiments. Investigations of the effects of the nitrogen source on dopant incorporation will be included. Finally, this information will be applied to the growth and fabrication of simple devices such as LEDs and MESFETs, allowing further evaluation of the layer quality pertinent to device applications. ***
