本論文主要探討如何利用氣壓輔助接觸轉印與遮罩植入式微影技術(Air Pressure Assisted Contact-Transfer and Mask Embedded Lithography) 製作商業化的高頻表面聲波 (SAW) 元件。
理論部份採用B.P. Abbott所提出的模態耦合理論作為高頻表面聲波元件的表現模擬方法，其中主要的參數為波傳損失、反射係數、電性轉換係數、金屬薄膜電阻、單位長度電容及表面波速。
接觸轉印法主要是用來製作微機電製程中所需要的遮罩 (Mask)，而氣壓輔助法是利用氣壓可以均勻的施力於物體的表面上，即使是不平的表面，因此可以得到較佳的轉印效果，以厚度約50 nm的鉻金屬為遮罩，直接以氣壓輔助奈米壓印機轉印到已旋塗聚甲基丙烯酸甲脂樹脂(PMMA) 的壓電基板上，接著再利用反應式離子蝕刻機 (RIE)，以氧電漿蝕刻無覆鉻層的部份，再以電子束蒸鍍機鍍上作為電極用的鋁層，最後再以丙酮舉離 (lift off) 剩餘之PMMA及鉻層，便完成所需的高頻表面聲波元件。此外本文亦將討論模仁重覆使用之議題。
以向量式網路分析儀量測所製作之高頻表面聲波元件，並與理論求得之結果作比較。

This paper will discuss how to use “Air Pressure Assisted Contact-Transfer and Mask Embedded Lithography” method for fabrication of high frequency surface acoustic wave (SAW) devices that is already used in some communication module.
We will analyze the SAW devices by using “Coupling-of-Modes” (COM) theory that is presented by B.P. Abbott et al. The 6 major parameters: propagation loss, reflection coefficient, transduction coefficient, thin film resistance, distributed finger capacitance, and the surface acoustic wave velocity will be discussed.
The contact-transfer imprinting method is newly developed to fabricate the metal mask layer of the MEMS process in recent years. And the air assisted contact-transfer imprinting method will lead to a more stable and better result due to its uniform pressure while imprinting. First, we use 50 nm Cr layer for the mask. Then we use O2 plasma to etch the PMMA layer. Finally, we get the SAW devices by using acetone to lift off.
We will demo how to use network analyzer to verify the SAW devices and imprinting mold re-use method in this paper.

[1] 王誌麟，零組件雜誌，西元2009年8月號

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