Study Of Polystyrene Film Swell/Shrink Process By In-Situ Ellipsometry

Spectroscopic ellipsometry (SE) is an optical technology which study on the surface, interface and thin film analysis. According to the change of polarization before the reflection of polarized light at the sample surface and after, the structural information were obtained. The application of SE is not limited to measure material thickness and characteristics, it has also been developed to control the process of information collection, geometry, anisotropy, defects and quantum confinement effect of nano structures.The study will be carried out as follow:(Ⅰ) Studying the swell/shrink behavior of polystyrene film by in situ ellipsometry. Using of a home-made sample cell, the polystyrene film with silicon wafer as substrates swell in the atmosphere of THF, and then shrink in the atmosphere of ethanol, using single-wavelength ellipsometry tracking the dynamic changes of thin-film structures, describing the swell/ shrink behavior.(Ⅱ) The multi-wavelength ellipsometry gave the information of film in different states. Surface morphology characterized by AFM(atomic force microscope) and PM(polarization microscope). The results illustrate that the film thickness growth and reduction are non-linear. Maxim swelling ratio and thickness variation curve depend on the initial thickness of film and the intensity of atmosphere.(Ⅲ) Studying the phase transition behavior of poly-octyl fluorene by in situ ellipsometry.