Electric Conductivity of Diamond Films

The so-called surface conductivity was studied extensively. For films saturated with hydrogen it is about arising from a concentration of charge 

However, this is only true for hydrogenated surfaces. With the diamond featuring a different surface structure, other effects come to the fore. Reconstructed surfaces, for instance, bear tt-bonds that may be arranged in various ways on the main crystallographic faces (Section 6.2.2). The surface dimers present on the (lOO)-plane, for example, cause the respective orbitals to split into a n- and a n - 

Nanocrystalline diamond films also frequently show remarkable conductivity that is primarily attributable to the large portion of atoms situated in grain boundaries. The sp -hybridized carbon atoms generate electronic states within the diamond s bandgap. These lead, for instance, to the so-caHed hopping conductivity, that is, a conductance arising from a successive hopping from one state to the next. 

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