STM investigations with atomic resolution on the (2x1) monohydride natural doped diamond (100) surface

We investigated natural p-doped (100) diamond by means of STM. To achieve a smooth and clean surface, the diamond was polished in a hydrogen plasma at 870 degrees C. In contrast to previous work, the STM measurement have been done on an etched and not on an overgrown diamond surface. After the hydrogen treatment the surface was free of any contamination, and we characterised the smoothing process with AFM and LEED. While the roughness of the surface was determined by AFM to be lower than 0.8 nm (RMS) LEED showed a (2 x 1) reconstruction without any annealing. UPS measurements revealed the surface to have a negative electron affinity (NEA). STM at ambient conditions showed dimer rows of the (2 x 1) monohydride reconstructed surface. Large atomically flat terraces (>17 mm x 17 nm) were found on the hydrogen-plasma treated surface, which is an indication of effective surface polishing.