Properties of SiOxNy Thin Films Deposited with a Single Molecular Precursor by Using RF PECVD

Abstract

We have deposited SiOxNy thin films on both Si(100) and glass substrates by using a tetraethyl orthosilicate (TEOS) single precursor at nitrogen flow rates of 0 ∼ 100 sccm by using a radiofrequency Plasma Enhanced Chemical Vapor Deposition (PECVD) method. The film growth orientation and microstructural characteristics were analyzed by scanning electron microscopy (SEM) and atomic force microscopy (AFM). Deposition at higher nitrogen flow rates results in finer clusters with smaller grain sizes. Moreover, we used UV/Vis and FT-IR spectroscopy and ellipsometry to investigate the optical properties for various nitrogen flow ratios. As-deposited SiO2 films showed an amorphous structure, but samples annealed in an O2 ambient at 900 ◦C showed increased crystallinity. Also, the leakage current densities of the SiO2 and the SiOxNy films annealed at 900 ◦C in an O2 ambient were about 4.0 × 10−8 and 1.5 × 10−7 A/cm.