表面聲波元件的製程

Fabrication process of SAW devices

黃柏翔(Bo-Siang Huang)

指導教授 ： 葉鳳生

國立清華大學/電機資訊學院/電子工程研究所/碩士(2007年)

摘要

本論文的目的在於表面聲波元件的製程，我們主要分成三個部分：第一部份，我們使用實驗室自行組裝的LP-MOCVD系統，沈積鋁以及氮化鋁膜，並且找出其最佳的沈積條件。第二部份，我們利用μ-contact printing 技術將aminosilane轉印到鋁膜上。最後，我們利用金屬反應式蝕刻方式製作transducer fingers。
首先，我們沈積鋁膜於Si和SiO2基板上以及沈積氮化鋁薄膜於SiO2和sapphire基板上，去了解substrate dependent of CVD aluminum and aluminum nitride thin films。在溫度400~600℃、Ar流量100~200sccm、反應壓力0.6~2torr條件下成功的在SiO2基板上沈積出鋁膜。在溫度850~950℃、 NH3:Ar=10:1~30:1、反應壓力0.6~4torr條件下成功的在sapphire基板上沈積出氮化鋁膜。然後我們利用μcontact printing技術在壓力10~200psi、溫度100℃、時間1min的條件下在鋁膜上轉印出線寬2μm、高度190~260nm的圖形。最後，我們利用金屬反應式離子蝕刻方式製作線寬1μm的鋁線。

關鍵字

表面聲波

並列摘要

Abstract
In this thesis, our object is the fabrication process of SAW device, we divided our work into three parts： First, we used the LP-MOCVD system to deposited aluminum and aluminum nitride thin films, and found out the optimum deposited condition. Secondly, we used μ-contact printing technique to transfer aminosilane on aluminum substrate. At last, we fabricated the transducer fingers by using RIE.
First at all, we deposited aluminum thin films on Si and SiO2 substrate and aluminum nitride on SiO2 and sapphire substrate to understand substrate dependent of CVD aluminum and aluminum nitride thin films. The aluminum thin film was successfully deposited on SiO2 substrate with temperature 400~600℃、Ar flow 100~200sccm、reactive pressure 0.6~2torr. The aluminum nitride thin film was successfully deposited on sapphire substrate with temperature 850~950℃、NH3 : Ar =10 :1~30 :1、reactive pressure 0.6~4torr.
Secondly, we transfer aminosilane wire width of 2μm on aluminum substrate with imprinting pressure 10~200psi、temperature100℃、imprinting time 1 min by μ-contact printing technique. The altitude of aminosilane was 190~260nm.
At least, we fabricated the aluminum wire line of 1μm by metal-reactive ion etching system.

參考文獻

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