Influence of ion-beam energy and substrate temperature on the synthesis ofcarbon nitride thin films by nitrogen-ion-assisted pulsed laser deposition

Carbon nitride thin films were deposited on silicon wafers by pulsed KrF ex cimer laser (wavelength 248 nm, duration 23 ns) ablation of graphite with a ssistance of nitrogen ion beam bombardment. X-ray photoelectron spectroscop y, Raman spectroscopy, and ellipsometry were used to identify the binding s tructure, nitrogen content, and optical properties of the deposited thin fi lms. The influence of the nitrogen ion beam energy on the compositional, el ectronic, and optical properties of the deposited thin films was investigat ed. The thin films deposited with nitrogen ion bombardment had an N/C ratio of 0.43. Raman spectroscopy measurements indicated the formation of CN tri ple bonds in the deposited thin films. The optical band gap E-opt was obser ved to decrease with the nitrogen ion energy. A nitrogen ion energy between 50 and 100 eV was deduced to be the optimal condition for depositing the c arbon nitride thin films. (C) 1999 American Institute of Physics. [S0021-89 79(99)01521-2].