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 achi eve a smooth and clean surface, the diamond was polished in a hydrogen plasma at 870 degrees C. In contrast to previous work, the STM measur ement have been done on an etched and not on an overgrown diamond surf ace. After the hydrogen treatment the surface was free of any contamin ation, and we characterised the smoothing process with AFM and LEED. W hile the roughness of the surface was determined by AFM to be lower th an 0.8 nm (RMS) LEED showed a (2 x 1) reconstruction without any annea ling. UPS measurements revealed the surface to have a negative electro n affinity (NEA). STM at ambient conditions showed dimer rows of the ( 2 x 1) monohydride reconstructed surface. Large atomically flat terrac es (>17 mm x 17 nm) were found on the hydrogen-plasma treated surface, which is an indication of effective surface polishing.