Optical and structural properties of silicon nitride thin films prepared by ion-assisted deposition

✍ Scribed by Shih-Liang Ku; Cheng-Chung Lee

• Publisher: Elsevier Science
• Year: 2010
• Tongue: English
• Weight: 484 KB
• Volume: 32
• Category: Article
• ISSN: 0925-3467
• DOI: 10.1016/j.optmat.2010.01.032

✦ Synopsis

Silicon nitride (SiN x ) films were prepared by ion-assisted deposition process. The films were analyzed by measurement of scanning electron microscopy (SEM), Fourier transform infrared spectrometry (FTIR), Xray photoelectron spectrometry, spectrophotometer, and ellipsometer measurements. The effects of Nion current density (J) on the structural and optical properties of SiN x thin films were investigated. The SEM studies revealed that films deposited at a higher value of J had highly condensed structure. FTIR analysis indicated an extremely low hydrogen content in the IAD films. It was found that the N/Si ratio of films increased when J increased. The optical constants and the optical band gap of films were determined. The stoichiometric Si 3 N 4 thin film was obtained with a high refractive index of 2.073 (at a wavelength of 400 nm), an extinction coefficient less than 6 Â 10 À4 , and an optical band gap of 4.57 eV.