Electrostatic force microscopy study of electrical conductivity of hydrogen-terminated CVD diamond films

Abstract

Electrostatic force microscopy (EFM) has been used to probe the conducting properties of the hydrogen-terminated (H-terminated) surface of CVD diamond films. Two parallel electrodes, separated by a distance of 100 mu m, are fabricated on the sample surface. EFM images the voltage distribution over a current-carrying H-terminated diamond film. The almost linear voltage drop in highly conductive H-terminated diamond surface layers indicates that the layers behave as diffusive conductors with a well-defined value of the sheet resistance. On the other hand, conductive as well as insulating regions are observed to coexist for H-terminated diamond surfaces with poor electric conductivity. (C) 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.