Characterization and modification of carbon nitride films deposited by laser ablation under low energy ion‐beam bombardment

Carbon nitride thin films with N‐concentration about 41% were synthesized by YAG pulsed laser ablation of graphite under a low-energy (<50 eV)nitrogen ion-beam bombardment. The results of electron diffraction (ED) and X‐ray photoelectron spectroscopy (XPS) analyses suggested the existence of β‐C₃N₄ polycrystallite grains in the amorphous carbide matrix of the deposited films. Optical emission spectra of the laser produced graphite plasma using different output wavelengths of a Nd:YAG laser, 355, 532 and 1064 nm were studied. The emission spectra showed that the plasma produced by the 355 and 1064 nm laser ablation contained a high concentration of excited C₂ radicals while in the case of 532 nm ablation, a relatively higher concentration of excited atomic carbon radicals was found in the plasma. A post‐treatment of the deposited films using low‐energy (50 eV) nitrogen ion‐beam bombardment was carried out in order to improve the concentration of β‐C₃N₄ structures in the films. This revised version was published online in July 2006 with corrections to the Cover Date.