Electrophysical parameters of Au-Ti ohmic contacts to polycrystalline diamond

Ohmic contacts to polycrystalline diamond thin films were formed using Au-Ti metal structure. The current-voltage characteristics of all contacts are linear and symmetric. Measured values of contact resistivity are less than 1 % of semiconductor resistivity. Essential variation of electrophysical parameters was not observed after rapid thermal annealing at 800 °C with 60 seconds duration. The thermionic emission was determined as dominant current transport mechanism through metal-diamond interface at temperatures above 190 K. The structure study was conducted by Auger profiling and X-ray diffraction analysis. The ability of using such type of ohmic contacts as temperature detectors on heat sink was discussed.