9704070 Weimer This award provides partial support for the acquisition of a thermogravimetric/ differential analyzer to be used for fundamental materials synthesis reaction kinetic studies of nitrides at high temperatures. The basic kinetic studies will be on the synthesis of nitrides, carbides, borides, and other bulk powders as well as nitride films deposited on substrates. The system will be capable of measuring powder, granular and solid materials in alumina, graphite, and platinum crucibles. Synthesis studies will include carbothermal reduction, direct nitridation, and gas phase reactions. The combination of high temperature synthesis studies to be carried out on large samples to allow for sufficient sampling of the materials for analysis. This capability is important for advancing our knowledge of nitrides, which have higher thermal capacities than silicon based materials, and have optical-photonic importance for communications. %%% This equipment award will support the research program for the investigation of the mechanism and kinetics for the synthesis of nitride, carbide, boride, and other non-oxide materials using high temperature thermogravimetric/differential analyzer. The instrument will provide a combination of high temperature with large loading capacity which is unique compared with conventional equipment, and will allow fundamental high temperature synthesis studies to be carried out on large samples, allowing for sufficient sampling of the material for analysis. The production of nitride powders is currently limited. There is considerable technological interest in producing structures with nitrides, and some recent examples of success. This capability is important for advancing our knowledge of nitrides, which have higher thermal capacities than silicon based materials, and have optical-photonic importance for communications. ***
