微機電系統（Micro-Electro-Mechanical System，簡稱MEMS）是當前科技界公認本世紀最具發展潛力的研究領域之一。當今微機電技術的發展可歸功於半導體製程技術的蓬勃發展，卻因此而更加發揚光大，不再限於電的特性，更兼顧了機械、光學、熱力學、流體力學等特性，逐漸的發展出不同性質的產品，其中行動通訊領域更是其中一項應用。平日最常用的行動通訊系統首推行動電話，它在短短幾年中成為全球發展最快速的展業，原因乃是因為電信的自由化與其使用學習門檻很低。
行動通訊的要求越輕、越小、越省電，希望將大多數的元件整合在一起，以減低元件數量，降低製造成本，但是到目前為止，仍不會缺少的元件包括：低雜訊放大器（LNA）、表面聲波濾波器（SAW Filter）、多工器（Duplexer）、電壓控制震盪器（VCO）、調解電壓器（Mod/Demodulator）及訊號處理單元。

本文的目的乃是利用鑽石薄膜沈積技術，製作鑽石薄膜表面聲波濾波器，用來改進目前以線寬不斷縮小的方法，來達到較高頻段濾波效果的設計，多加入了鑽石薄膜，其聲波傳遞速率以倍數成長，如此一來，當元件需求往高頻段發展時，受其限制會因此減低。並利用當前常用的分析模型，從壓電基板觀點、交指叉電極能量觀點，以達到其最佳設計之目標，再加上製程部分的整合，與高頻元件量測機台的配合，期望能以目前微機電技術製作出一高Q值、高訊號/雜訊比、且濾波效果良好之輕薄短小的鑽石薄膜表面聲波濾波器。

Micro-Electro-Mechanical System (MEMS) is one of the potential research topics in this century and has rapidly grown in many different kinds of products, including communication. The advantages of the portable communication are lighter, smaller, and power-saved. It is until now the SAW devices are essential in mobile phone as the other devices are integrated in a chip. This study analyzes and designs a basic diamond film surface acoustic wave filter to obtain higher frequency filtering effect by reducing the line width of the electrodes. Since the diamond has the highest speed of the acoustic wave in all materials, the process limitation of the line width of electrode is not restricted if the higher frequency devices are required.
The effective surface permittivity method is successfully used in this study to estimate the values of the electromechanical coupling coefficient for bulk materials and multi-layer structures. The theoretical analyses of the three models show that the frequency responses of the different SAW devices can be simulated through specifying the parameters of each device. Furthermore, it shows that the simulation results agree well with the experimental results.

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