Effects of plasma power on the properties of transparent SiOCH, plasma-polymerized methylcyclohexane and multi-layer films deposited by using the one-chamber low-temperature plasma deposition process

In this work, SiOCH and plasma-polymerized methylcyclohexane (pp-MCH) films and pp-MCH/SiOCH multi-layers for applications to transparent diffusion barrier layers were deposited by using low-temperature plasma-enhanced chemical-vapor deposition (PECVD). In particular, onechamber plasma processing was applied for multi-stack layer deposition using hexamethyldisiloxane (HMDSO)/O₂/Ar gas and methylcyclohexane (MCH)/Ar gas mixtures for SiOCH and pp-MCH layers, respectively. Increasing the RF plasma power enhanced the dissociation of HMDSO and MCH precursors, leading to an enhanced deposition rate and less incorporation of organic groups into the films. Even though the optical transmittance values measured by using ultraviolet-visible spectroscopy at shorter wavelength of less than 400 nm were decreased more with increasing RF power, the deposited films showed good transmittance (≥9 %) in the visible region. Increased protective efficiencies of SiOCH and pp-MCH films up to maximum values of 99.84 % and 99.57 % at 700 W, respectively, with increasing RF power are attributed to the enhanced formation of SiO₂ and C=C bonding configurations for each film.