TiC contacts on B-doped polycrystalline diamond were studied. The as-deposited TiC formed rectifying contacts with a reverse leakage current of 0.4 μA at 5 V. After the contacts had been annealed at 850 C at a vacuum of approximately 1 × 10-8 Torr, the current-voltage (I-V) characteristics of the contacts changed little and the rectifying nature was retained. The primary observable change was that the leakage current at 5 V reverse bias increased from 0.4 to 0.7 μA. The thermal stability of the rectifying contacts was attributed to the chemically non-reactive interface between the diamond and TiC. © 1993.