GROWTH AND CHARACTERIZATION OF CARBON NITRIDE THIN-FILMS PREPARED BY LASER-ABLATION

Rutherford Backscattering Spectrometry (RBS) has been systematically a pplied to determine the composition of carbon nitride thin films prepa red by laser ablation at different substrate temperatures, The films w ere deposited onto silicon and aluminium substrates by irradiating a g lassy graphite target with an ArF excimer laser (193 nm) in a reactive ammonia atmosphere. The characterization was completed with the addit ional analysis techniques Energy Dispersive X-ray Spectroscopy (EDS). Fourier Transform Infrared Spectroscopy (FTIR) and profilometry. The r ole of the substrate processing temperature on the film growth and pro perties is investigated. RES measurements indicate that the concentrat ion of nitrogen decreases from 23 to 9 at.%, as the temperature is inc reased up to 300 degrees C. The infrared analyses show that nitrogen i s bonded to carbon in different configurations (1300-1650 cm(-1)) and the presence of hydrogen in the layers forming CHx and NHx groups. For this new material. several calibration diagrams for often-used techni ques, such as EDS and FTIR, are presented. The inverse absorption cros s section of the C=N vibration mode, as well as the calculation of the apparent activation energy of the process are reported. (C) 1998 Else vier Science B.V.