EFFECT OF SURFACE TERMINATION ON THE ELECTRICAL-CONDUCTIVITY AND BROAD-BAND INTERNAL INFRARED REFLECTANCE OF A DIAMOND(110) SURFACE

Large variations in the broad-band reflectance (similar to 3.4% per re flection at 5000 cm(-1)) were observed in the multiple-internal-reflec tion infrared spectrum of a diamond (110) surface upon surface chemica l modification. Larger changes in reflectivity were observed for s tha n for p polarization, consistent with a reflectivity change that resul ted from modification of the surface. The effect of surface terminatio n on the electrical conductivity of the diamond (110) surface was meas ured in vacuo. The bare surface was most conductive (<1.7 x 10(7) Omeg a/square), followed by the hydrogenated surface (similar to 6.0 x 10(7 ) Omega/square), and the highly insulating oxidized surface (>10(12) O mega/square). The internal reflectance of diamond decreases as the sur face becomes more conductive.