SICXNY THIN-FILMS ALLOYS PREPARED BY PULSED EXCIMER-LASER DEPOSITION

In this work, thin films of SiCN have been deposited by pulsed laser d eposition on silicon substrates by KrF (248 nm) excimer laser ablation of a SIC sintered target in a vacuum system at room temperature. To o btain various stoichiometries, molecular nitrogen is introduced in the deposition chamber in the 5 to 500 mTorr pressure range. The resultan t SiCxNy films are compared to the one prepared in a high vacuum envir onment (no N-2 gas). The film growth was monitored by real-time kineti c ellipsometry at a single photon-energy (2.5 eV). The film was analyz ed by spectro-ellipsometry in the photon-energy range of 1.5 < hv < 5. 0 eV at the end of the deposition process. Tauc's plots are used to es timate the optical band-gap of the films as a function of the N-2 gas pressure. High resolution in situ X-ray photoelectron spectroscopy cha racterization was performed on every film. The bonding character of th e elements in the films is obtained by deconvoluting the XPS peaks. Th e ellipsometric and XPS results suggest that a new phase alloy is pres ent in the SiCxNy films. (C) 1998 Elsevier Science B.V.