Optical and morphological propel-ties of laser photo-deposited hydrogenated CNx thin films

The optical and morphological properties of hydrogenated carbon nitride thi n films obtained by ArF excimer laser photodeposition (lambda = 193 nm) fro m different ammonia/acetylene mixtures were investigated. The optical prope rties of the films depend on the nitrogen content. The band gap deduced fro m measurements of the optical absorption coefficient in the UV-VIS spectrum is found to be superior to 2.3 eV. Film thicknesses and refraction indexes were investigated by m-lines spectroscopy The refraction index varies from 1.66 to 1.72. The microstructure of the deposited films as revealed by sca nning and transmission electron microscopy is discussed as a function of th e deposition parameters. 2000 Elsevier Science B.V. All rights reserved.