本研究為應用電濕潤（electro-wetting on dielectrics, EWOD）原理驅動斜面上之微液滴，並透過改變電濕潤的驅動頻率，研究不同的驅動頻率對液滴於斜面上的動態行為所造成的影響。主要實驗設計為利用共平面式（coplanar）不對稱（asymmetric）之電極設計理論以及微機電製程加工技術來驅動微液滴於電極表面上做特定方向的驅動。
　　液滴於斜面運動的影響因素之一為振動效應，本研究透過對球缺液滴進行共振頻率(Resonant Frequency)及共振模態對液滴動態行為的探討，經本研究的分析後發現液滴在共振模態時會以Stick-Slip的行為在運動。
而Stick-Slip的動態行為會與一般的電濕潤驅動不完全相同，造成此種運動狀態的原因是電濕潤效應的反應時間與共振模態所致。經由分析n=2之共振模態液滴於斜面上的運動狀態後，除了證明振動對液滴的移動速度具有影響力外，液滴的共振模態與其內流場也會影響液滴的運動行為，使液滴產生Stick-Slip的動態行為及具有較大的移動速度。

　In this study, the dynamic behaviors of a droplet driven by EWOD (electro-wetting on a dielectrics) device with varying input frequencies on an inclined plane are investigated. New triangular coplanar EWOD electrodes fabricated by using MEMS technology are designed to generate driving force on a droplet. When a square wave signal is applied, the EWOD device generates asymmetric electro-wetting force that can drive a droplet to move in a specific direction.
　One of the main factors that affects droplet dynamic motion is the droplet oscillation behaviors. In this study, different resonant mode frequencies of a sessile droplet are first analyzed. It is found that the resonant modes that can happen on horizontal or inclined planes are the even number modes only for EWOD actuation. Odd number modes cannot exist. The droplet moving speed on an inclined plane has been also studied. The droplet moving speeds at resonant modes are higher than those not at resonant modes. In addition, the highest sliding velocity and the droplet dynamic “Stick-Slip” motion are found at the resonant mode n=2. By analyzing the droplet motion on a plane with inclined angle of 25°. This study proves that resonant dynamics of a droplet significantly affects behaviors of the droplet movement, as well as its sliding velocity.

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