抓式致動器 (SDA)由於其高操作頻寬、高輸出力、工作範圍廣與單位步進制御能力佳，而在微光電系統與微組裝應用中具有潛力。然而，抓式致動器之致動原理受到其幾何尺寸的影響很大，如何精確預測抓式致動器之單位步進距離，是目前缺乏但在設計時卻迫切需要的。本文提出一有限元素模型以建立幾何尺寸的設計規範，並與過去研究之實驗數據比對，以證實模型的可信度。幾何尺寸對於模擬分析結果顯示較小的抓式致動器板長、板寬，適當的板厚與較大的軸襯高度，可以得到較大的單位步進距離設計。此外，為了驗證模型之可信度，本文設計一包含檢視單位步進距離、長距離操作、高頻操作與輸出力之測試晶片，並利用TSMC CMOS 0.35 um 兩層多晶矽四層金屬 3.3V/5V製程，以金屬層作為主結構完成抓式致動器之設計。透過分析，在峰值電壓為100伏特的操作下，板長為52 um、板寬為75 um、板厚為0.64 um與板寬為3.33 um為能提供最大的單位步進距離，高達192.6 nm。後製程則將利用高選擇比的乾蝕刻與溼蝕刻完成抓式致動器的結構釋放。

　　Scratch drive actuator (SDA) has been proposed in microsystem applications. However, analysis of precise stepwise displacement is critical to the design of scratch drive actuator. A finite element model is developed in this work. The simulation results have been verified by comparing with the experiment data reported previously. The geometry effects of the SDA plate length, plate width, plate thickness, and bushing height have been found through the finite element model. The model is shown to be compatible with various material properties in different fabrication process. Design of the SDA has been implemented under TSMC (Taiwan semiconductor manufacturing company) CMOS (complementary-metal-oxide- semiconductor) 0.35 μm Mixed Signal 2P4M Polycide 3.3V/5V (2P4M) fabrication process. Analysis shows that the stepwise displacement is 192.6 nm for SDA of 52 um in plate length, 75 um in plate width, 0.64 um in plate thickness, and 3.33 um in bushing height under the 100 volt peak voltage. Post-CMOS by dry etch process and wet etch process for high selectivity etching are also developed for releasing the SDA structure.

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