Atmospheric pressure PECVD of SiO 2 thin film at a low temperature using HMDS/O 2/He/Ar

Abstract

SiO 2-like thin films were deposited at a low temperature (< 50 °C) by a remote-type, atmospheric pressure plasma enhanced chemical vapor deposition (AP-PECVD) using a pin-to-plate-type, dielectric barrier discharge with gas mixtures containing hexamethyldisilazane (HMDS)/O 2/He/Ar. The film characteristics were investigated according to the HMDS and O 2 flow rates. To obtain a more SiO 2-like thin film, an adequate combination of HMDS and oxygen flow rates was required to remove the –(CH 3) x bonding in the HMDS and to oxidize the Si in HMDS effectively. At the optimized flow rates, the surface roughness of the SiO 2-like thin film was also the lowest. By using HMDS (50 sccm) and O 2 (500 sccm) flow rates in the gas mixture of HMDS/O 2/He (2 slm)/Ar (600 sccm), SiO 2-like thin films with a low impurity (< 6.35% C) were obtained at a deposition rate of approximately 10.7 nm/min.