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 (∼3.4% per reflection at 5000 ${\mathrm{cm}}^{\mathrm{-}1}$) were observed in the multiple-internal-reflection infrared spectrum of a diamond (110) surface upon surface chemical modification. Larger changes in reflectivity were observed for s than for p polarization, consistent with a reflectivity change that resulted from modification of the surface. The effect of surface termination on the electrical conductivity of the diamond (110) surface was measured in vacuo. The bare surface was most conductive (<1.7×${10}^7$ Ω/□), followed by the hydrogenated surface (∼6.0×${10}^7$ Ω/□), and the highly insulating oxidized surface (≳${10}^{12}$ Ω/□). The internal reflectance of diamond decreases as the surface becomes more conductive.