Morphological and electrical characterization of FIB implanted diamond surfaces

We report on the realization of amorphous diamond films obtained by means of Ga+ focused ion beam at different ion dose. We implemented a novel methodology, which combines a selective removal of amorphous carbon material and atomic force microscopy to collect topographic maps and height data. The procedure allowed for a precise measurement of the resistivity of amorphous carbon film by using actual film thickness values instead of data obtained from simulations or theoretical calculations. Large area Ti contacts overlapping the amorphous carbon layer surface were used for current-voltage measurements. An ohmic behavior characterized by a low contact resistance was found. Conversely, the local probing of the amorphous diamond surface with the conductive tip of a C-AFM evidenced an inhomogeneous conductive behavior, ranging from nearly ohmic to nearly rectifying, and a dose dependent surface conduction. (C) 2015 Elsevier B.V. All rights reserved.