Ternary and Quaternary Nitrides

Cornell University, Ithaca NY

Investigators

Abstract

Non-Technical Abstract This project will explore the preparation and existence of ternary and quaternary nitrides and study their properties. There are already many important uses of binary nitrides. These include aluminum nitride (high thermal conductivity substrates), silicon nitride (coatings for electronics, etc.), titanium nitride (hard coatings for tools), tantalum nitride (metallic conductors and diffusion barriers in electronics, colored surfaces in jewelry, artistic displays, etc.), niobium nitride (thin film super-conducting devices), gallium nitride (blue LEDs, high speed high power electronics). As is known from oxide chemistry, ternary and quaternary compounds offer a greater, more tunable, qualitatively different and more useful set of properties than the binaries alone. So it is reasonable to expect that ternary and quaternary nitrides will eventually provide the same, since so many useful binary nitrides are known and since structurally interesting compounds have been found, some with unusual properties. It is expected that some of these new nitrides will find utility in microelctronics or photonics. This research will also be a vehicle for the training of undergraduates, graduate students and postdocs in forefront techniques and methods of Solid State Science. Interactions with industry will continue. Technical Abstract The preparation and existence of ternary and quaternary nitrides will be explored and their properties will be studied. Molten metals and their alloys with lithium nitride, the only congruently melting nitride, will be used as fluxes (solvents) to prepare multinary nitrides and to examine them for potential technological uses and for novel phenomena. Initial results suggest that these fluxes and alloys of these fluxes will be highly useful in producing a large number of new compounds with novel structures and properties. This research will also be a vehicle for the training of undergraduates, graduate students and postdocs in the science and art of modern Solid State Chemistry. Our results have been and will be widely disseminated via the WEB, publications, seminars, professional meetings and, where appropriate, via patents.