As the structure formations are miniaturized into nanometer range, the instability properties become more and more important. The instabilities are triggered from a various kinds of sources. In our study, the instability factor caused by external electric field is studied. Electrohydrodynamic (EHD) instability has been studied in a variety of liquids. As an external electric field is applied, the polymer thin film will be polarized and the liquid/liquid or liquid/air interface where the free charges are present is perturbed consequently.
Here, the kinetic studies of the polymer column growth are investigated. The polymeric material, poly(methyl methacrylate) (i.e. PMMA), was chosen. Two parameters varied with electric field are the applied voltage U and the polymer film thickness l0. According to those parameters (i.e. U and l0), we investigated how they influenced the growth of the polymer films with different annealing times and obtained the morphology of the polymer surface from atomic force microscope (AFM). Because the viscosity of polymer is varied with the temperature, the annealing temperature is also considered as the factor influencing the growth of polymer pillars in the study. As annealing temperature elevates, the viscosity of polymer decreases that leads to the increase in mean height and growing rate of polymer pillars.

Contents
致謝 I
Abstract II
Contents III
Figure Captions V
List of Tables X
Chapter 1 Introduction 1
Chapter 2 Experiment 1
2.1 Materials.. 8
2.2 Sample Preparation. 8
2.2.1 Top Plate. 8
2.2.2 Bottom Plate. 10
2.3 Experimental Procedure 10
2.4 Differential Scanning Calorimeter (DSC) .. 11
2.5 Thermogravimetric Analysis (TGA) . 11
2.6 Contact Angle Measurement. 12
2.7 Atomic Force Microscope (AFM). 12
Chapter 3 Results and Discussion 21
3.1 Electrostatic Pressure 21
3.2 Evolution in Time 23
3.3 Mean Height Measurement 23
3.3.1 Applied Voltage Effect 24
3.3.2 Film Thickness Effect 25
3.3.3 Annealing Temperature Effect 26
3.4 Characteristic Wavelength Analysis 27
3.4.1 Applied Voltage Effect 29
3.4.2 Film Thickness Effect 29
3.5 Dewetting Effect 32
3.6 Discharge Effect 33
Chapter 4 Conclusions 64
References 65

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