奈米壓印技術應用於表面聲波元件之研究

The Study of Nano Imprint Technology on Surface Acoustic Wave Device

張宇舜(Yu-Shun Chang)

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(2008年)

摘要

本論文的目的在於表面聲波元件的製程，由簡單的RTA-MOCVD系統，以不破真的方式成功地在sapphire基板上鍍製壓電層AlN(002)和電極層鋁膜，再以奈米接觸式壓印(nano-contact imprint)方式做出IDT結構以達低成本SAW Filter的製作。

首先，為了找出最佳條件，我們混合precursor 三甲基鋁(TMAL)和NH3以不同氣體流量比1:10~1:25，在溫度850℃~950℃、反應壓力0.6~4torr，在sapphire上鍍製氮化鋁薄膜，並且也使用TMAL當作source，在溫度500℃~600℃於SiO2上沉積鋁膜。我們由XRD、XPS、Auger分析可以得知氮化鋁和鋁膜的結晶特性、元素組成以及原子濃度百分比。

第二部份，我們備製線寬150nm和200nm其線寬與線距為1:1、1:10 的模仁，將aminosilance沾印在模仁上，然後使用奈米接觸式壓印技術將aminosilane轉印到鋁膜上。打O2 plasma在鋁膜上，以增強aminosilance和鋁膜之間的adhesion。使用Nanonex-2000機台，試以不同壓印壓力15~25psi，在溫度100℃、時間30sec的條件下來完成壓印技術。我們使用AFM和SEM來觀察轉印後aminosilance的圖形。

最後，我們使用aminosilance當蝕刻阻擋層，來定義鋁線圖形。使用RIE-200L，通入氣體Cl2、BCl3和N2做乾式蝕刻後，我們可以得到IDT奈米鋁線。藉由AFM和SEM量測，我們可以得到蝕刻後鋁線的寬度和高度。

關鍵字

奈米壓印技術 ； 表面聲波元件 ； 氮化鋁薄膜 ； 化學氣相沉積 ； 三甲基鋁

並列摘要

The object of this thesis is the fabrication process of SAW device. In order to fabricate low-cost SAW filter, we used a simple RTA-MOCVD system to successively deposit piezoelectric AlN(002) film and aluminum electrodes on sapphire substrate without breaking vacuum, and fabricated IDT structure by nano-contact imprint technique.
Firstly, the precursor TMAL is mixed with NH3 at various rate 1:10~1:25 with temperature 850℃~950℃ at operating pressure 0.6~4 torr to deposit aluminum nitride thin film on sapphire substrate and find out the optimal condition. TMAL is also used to deposit aluminum films on SiO2 at temperature 500℃~600℃. The aluminum nitride and aluminum films are analyzed from XRD、XPS、Auger in order to crystalline properties、film composition and atomic concentration percentage.
Secondly, we prepared line width:space=1:1 and 1:10 molds with line width=150、200nm to transfer ink aminosilance on the mold. The nano-contact printing technique was developed to transfer aminosilane on aluminum film. The O2 plasma was applied on Al film to enhance the adhesion between Al film and aminosilance. The imprint pressure 15~25psi at temperature 100℃ for 30sec by Nanonex-2000 was performed from contact printing process. AFM and SEM were used to observe the aminosilance transferred patterns.
Finally, we used aminosilance as the etching mask to pattern Al line. After dry etching with gas Cl2、BCl3 and N2 by RIE-200L we fabricated IDT Al nano-wire. The width and height of Al line was observed from AFM and SEM.

並列關鍵字

Nano Imprint Technology ； SAW ； AlN thin film ； CVD ； TMAL

參考文獻

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