Electrical properties of pulsed UV laser irradiated amorphous carbon

Amorphous carbon films containing no hydrogen were irradiated with a pulsed UV laser in vacuum. Raman spectroscopy indicates an increase in the quantity of sp(2) clustering with the highest laser energy density and a commensurate reduction in resistivity. The reduction of resistivity is explained to be associated with thermally induced graphitization of amorphous carbon films. The high field transport is consistent with a Poole-Frenkel type transport mechanism via neutral trapping centers related to sp(2) sites which are activated under high fields. Decreasing the resistivity is an important feature for use of carbon as an electronic material. (C) 2008 American Institute of Physics.</p