Excimer laser ablation process characteristics for carbon nitride and diamond-like films preparation

We deposited diamond-like carbon (DLC) thin films and carbon nitride (CN) t hin films by KrF excimer laser ablation of graphite carbon target in helium , hydrogen, nitrogen and mixed nitrogen and hydrogen gas ambient conditions . We report spectroscopic properties of the laser plasma plume produced dur ing DLC and CN thin film deposition. Optical emission measurements at non-r eactive helium ambient gas showed the appearance of neutral and ionic speci es such as C and C+. Strong emission from molecules, CH, C-2 and CN produce d by the reaction in gaseous phase was observed with the ambient hydrogen a nd nitrogen gases. The properties of DLC and CN thin films are strongly aff ected by the laser plume dynamics. DLC and CN films were deposited on a qua rtz substrate and a single-crystalline Si(100) wafer at room temperature. T ypical deposited DLC and CN thin films had an optical band gap of similar t o 2.0 eV. (C) 1999 Elsevier Science Ltd. All rights reserved.