氮化鎵上氮化鋁之表面聲波振盪器對環境紫外光感測之特性研究

Fabrication study of UV sensors made of AlN/GaN SAW oscillator

林岳霆(Yueh-Ting Lin)

指導教授 ： 高慧玲

中原大學/工學院/電子工程研究所/碩士(2006年)

https://doi.org/10.6840/cycu200600234

摘要

近年來，由於一般民用產業及國防工業都需使用更好的紫外光感測器，以用於半導體製程監控(微影儀器校正)、太空通訊、臭氧層的破洞監測、紫外光天文學、火焰感測器、飛彈偵測以及空對空安全通信等應用，這些應用皆需具有高緊密度、高敏感度、高精密性、低功率耗損及高穩定性等特點。
現今的表面聲波元件已被廣泛地應用在各通訊產業上，另外也因為其高靈敏度適用在各類感測器上，而在製作紫外光感測器上，因為氮化鎵與氮化鋁具有寬能隙、低暗電流及高響應度等特性而倍受矚目，本文利用迴旋濺鍍系統在氮化鎵基板上沉積氮化鋁薄膜以製作表面聲波元件，由於氮化鋁薄膜與氮化鎵間晶格不匹配較小（~2.4%），因此能在氮化鎵基板上沉積結晶性較佳的氮化鋁薄膜，並且能改善氮化鎵表面聲波元件之特性，並與半導體、光電產業做結合。本文以此結構製成表面聲波振盪器，探討紫外光之波段及強度對頻率響應及直流特性上之影響，由實驗結果得知，本實驗室所成長之氮化鋁薄膜具有低暗電流（2.58×10-10 A,在10V偏壓下），而表面聲波振盪器具有可偵測波長365nm光源強度之能力。

關鍵字

紫外光偵測器 ； 表面聲波振盪器 ； 迴旋濺鍍系統 ； 氮化鋁 ； 表面聲波元件 ； 氮化鎵

並列摘要

In recent year, ultraviolet (UV) sensors are attractive due to various civil and military applications, such as semiconductor fabrication (lithography) monitoring、satellite communications、ozone layer monitoring、UV astronomy、flame detection、missile warning and space-to-space communications. High durability、high sensitivity、high compactness、low power and high reliability are critical requirements.
The surface acoustic wave (SAW) device has been used in modern communication. In addition, it suits to be sensors for its high sensitivity. In the region of UV sensors, GaN and AlN are most popular materials because of their wide bandgap、low dark current and high responsivity. In this thesis, AlN thin films were deposited on GaN/Sapphire at the low temperature of 300aC for SAW devices by using Helicon sputtering system. Due to the small lattice mismatch between AlN and GaN, epitaxial AlN films can be obtained on GaN. Superior SAW characteristics have been observed and demonstrated by depositing AlN on GaN. The thin film layered structure for SAW devices, with the combination of AlN and GaN may, in future, bring about the development of high frequency components which integrate and utilize their semiconducting, optoelectronic properties. The thesis presents a SAW oscillator using this structure. The output frequency of oscillator and the characteristic DC responded to the UV illumination with various wavelengths and intensity will be explored.

並列關鍵字

SAW oscillator ； ultraviolet sensor ； Helicon sputtering system ； Surface acoustic wave (SAW) ； GaN ； AlN

參考文獻

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