The Research Of SiCN Films Prepared By Magnetron Sputtering

SiCN is a new type of wide band-gap semiconductor materials, which has an excellent combination of optical, electrical and mechanical properties. Its compatibility with the silicon integrated circuits, unique luminescent properties and adjustable band gaps varying from UV to visible light range make SiCN thin films the optimized materials of optoelectronic integrated circuits.The SiCN thin films are prepared on the silicon and quartz substrate by RF reactive magnetron sputtering system. The high pure argon was used as sputtered gas, nitrogen as reacted gas, pure silicon and graphite as sputtering targets materials. The thickness, characteristics of composition, surface appearance, chemical bonding, crystal structure and photoluminescence of SiCN films were characterized by ellipsometer, X-ray photoelectron spectrometry, Fourier transform infrared spectroscopy, scanning electron microscopy, X-ray diffraction, ultraviolet-visible spectrophotometer and fluorescence spectrometry. This thesis also studies the impact of Si target sputtering power, C sputtering power, and the N2 flow rate on SiCN thin film relative systematacially.The research findings show that the SiCN thin films were constituted by elements of Si, C and N, and the structures were mainly formed of the Si-N, Si-C, Si-O, C-N, C=N, C-C and C=C bonds, which composed complex network. It is found that Si and C atoms occupy similar sites in the SiCN network, the improvement of Si (or C) target sputtering power helps increase Si (or C) content and reduce C (or Si) content. It will reduce Si content and increase C and N contents when enlarge the flow rate of N2. Due to surface oxidation and physical adsorption, a certain amount of the elements O are introduced to the films, and the content of O elements can indicate roughness. Meanwhile, the deposition rate of SiCN thin films will increase with the improvement of Si target sputtering power, C sputtering power or N2 flow rate. But an exorbitant target sputtering power was adverse to the deposition rate. SiCN films have good light transmission, and its optical band gap presents downward trend when C target power or N2 flow rate increases and rising trend when the Si target power increases. The origin of photoluminescence at 365nm,440nm/450nm,510nm/550nm respectively are amorphous silicon oxide defects, sp2 hybridization of C atoms and quantum confinement effect of β-SiC nanocrystals.