GaN is a direct, wide band -gap semiconductor (Eg =3.4 eV) which has a potential application in electronic and optical devices including UV-emitting lasers and bright p-n junction GaN light emitting diodes. In order to attain optimum device performance, it is necessary to develop lowresistance, thermally stable and uniform ohmic contacts.

In this study, the TiN/GaN contact synthesis and examination of contact performance were conducted at North Carolina State University. Si-doped n-GaN films were grown on 6H-SiC substrates via MOVPE with an A1N buffer layer. The TiN films were deposited in an ion-beam assisted, UHV electron-beam evaporation system. TiN growth was performed at a substrate temperature of 350 °C and a nitrogen pressure of about 2×10-4 torr. The deposition rate was 1- 1.5 nm/min. The TiN contacts deposited on (0001) n-GaN were ohmic with high resistivity in the as-deposited condition, but the resistivity decreased sharply in response to annealing. The TiN/GaN interface was examined by transmission electron microscopy to provide correlations between changes in microstructure and electrical behavior.