AVS 53rd International Symposium
    Plasma Science and Technology Tuesday Sessions
       Session PS3-TuP

Paper PS3-TuP2
Formation of Ultra Water-Repellent Thin Films in Organosilane Plasma by PECVD Method

Tuesday, November 14, 2006, 6:00 pm, Room 3rd Floor Lobby

Session: Advanced Plasma Deposition Poster Session
Presenter: Y.S. Yun, Nagoya University, Japan
Authors: Y.S. Yun, Nagoya University, Japan
T. Yoshida, Nagoya University, Japan
N. Shimazu, Nagoya University, Japan
Y. Inoue, Nagoya University, Japan
N. Saito, Nagoya University, Japan
O. Takai, Nagoya University, Japan
Correspondent: Click to Email
Ultra water-repellent films, inspired by water-repelling lotus leaves, have been attracted over the last few years to both fundamental research and practical applications. We have succeeded in fabricating ultra water-repellent thin films at room temperature by microwave plasma enhanced CVD using organosilicon compounds as raw materials. However, activated reactions in the PECVD process are too complicated to make clear its deposition mechanism. In this study, we investigated reactions in organosilane plasma by using optical emission spectroscopy and mass spectrometry in order to understand the formation reaction of ultra water-repellent thin films in the PECVD process. Surface morphology, chemical composition and bonding states of the films were analyzed. From the results, we found that there are several stages in formation of ultra water repellent thin films. That is, at the first stage of the growth, the nano-clusters seem to fall randomly on the surface. These clusters probably originate from a polymerization process in the gas phase and deposit on the substrate. When the film was deposited for several tens of seconds, the nano-clusters show a tendency to form chains or islands, which means the clusters must have a spatial preference. Finally, these films have particular nano-textures with nano-scale pores of a few hundreds nanometer in size among the cancellous web-like structure of the nano-cluster agglomerates. The rough surface of the films results in the water contact angles greater than 150 degree.