Super hydrophobic films synthesis by PECVD and mechanical &
chemical properties of the film
Joon S. Lee, Su B. Jin, Yoon S. Choi and In S. Choi, Jeon G. Han
Center for Advanced Plasma Surface Technology, Institute for Plasma-Nano Materials,
Sungkyunkwan University, 300 Chunchun-dong Jangan-gu, Suwon, Korea
e-mail: platinum87@skku.edu
Abstract
Super-hydrophobic surface has a contact angle greater than 150°. Due to the high
contact angle, very small amount of water droplet comes into contact with the surface.
So super-hydrophobic properties have attracted much interested for both fundamental
research and applications. The applications include self-cleaning, anti-fingerprint,
prevention of snow sticking, anti-fog, etc.
Designing and creating hydrophobic surfaces through adjusting the chemical
composition as well as the morphology of the surfaces has become a focus in the field
of material sciences. Hydrophobic properties of materials are usually obtained by
padding or coating processes using silicon or fluorine compounds. But current hurdle is
film deposition at low process temperature less than 100 C especially for polymer
treatment, because of the melting temperature of polymer is very low.
Hydrophobic film is deposited by PECVD process with RF plasma discharge which is
independently modulated for plasma parameter control.
Precursors which are
commercially available are used for film synthesis such as OMCTS, HMDSO, HMDS,
TEOS, etc. The typical film system for hydrophobic film synthesis on polymers
including PET and PC is comprised of interlayer coating of hard coating such as SiOx
and top coating of hydrophobic film. Surface chemistry is analyzed by FTIR. Surface
morphology change is analyzed by AFM. Hydrophobic property changes are evaluated
with boiling test at elevated salty water, pencil hardness test and cosmetic cream test etc.
Keywords: PECVD, hydrophobic film, HMDS precursor