表面聲波振盪器之設計與應用

The Design and Application of Surface Acoustic Wave Oscillator

吳宗騏(Chun-Chi Wu)

指導教授 ： 鄭湘原

中原大學/工學院/電子工程研究所/碩士(2005年)

https://doi.org/10.6840/cycu200500794

摘要

摘要

自英國物理學家雷利 (Lord Rayleigh)於西元1885年發現表面聲波以來，因西元1965年指叉電極轉換器(Interdigital Transducer)的發明才使得表面聲波元件普遍地被應用在電子設備中，例如頻率濾波器、諧振器、感測器等。在表面聲波感測器的應用上包括有溫度、溼度、氣體、壓力等量測。表面聲波感測器通常是由表面聲波元件及放大電路所組成的振盪器，可由振盪器的頻率偏移量得知感測的結果。當溫度、氣體等外在條件影響表面聲波元件的特性時，會改變表面聲波振盪器的頻率。
本文利用皮爾斯(Pierce)振盪電路架構設計振盪器，其中選擇使用台灣積體電路公司0.35微米金氧半導體製程設計振盪器的放大電路，其供給電壓為3伏特，搭配雙埠表面聲波延遲線元件，組成一個酒精氣體感測器，希望實現低成本、低電壓、離散元件少的表面聲波氣體感測器。
關鍵字：表面聲波元件、指叉電極轉換器、振盪器、感測器

關鍵字

感測器 ； 振盪器 ； 表面聲波元件 ； 指叉電極轉換器

並列摘要

ABSTRACT

Surface acoustic wave (SAW) was discovered by Load Rayleigh in 1885 and the surface acoustic wave (SAW) device has led to widespread use in electron devices due to Interdigital Transducer (IDT) was invented in 1965. These devices include frequency filters, resonators, and sensors. The applications of the SAW sensor are including temperature sensor, humidity sensor, gas sensor, and pressure sensor, etc. SAW sensors are typically constructed as SAW device and placed in the feedback loop of an amplifier, resulting in an oscillator. The oscillation frequency depends on the surface condition of SAW device and conveys information about the result of measurement. Any changes in extrinsic variables such as temperature and gas can produce a frequency shift in SAW oscillator.
The design of SAW oscillator has used Pierce oscillator circuit and two-port SAW delay line device. A CMOS amplifier is developed in a TSMC 0.35μm 2P4M CMOS semiconductor process under 3V power supply. In the end, the SAW delay line oscillator using MOS transistor as an amplifier will be applied in Alcohol gas sensor. The approaches are low price, low power, and less components in this design.

Keyword: Surface acoustic wave, Interdigital Transducer, sensor

並列關鍵字

sensor ； Surface acoustic wave ； Interdigital Transducer

參考文獻

5. 邱佳松, 高頻聲波振盪器之研究與應用, 中原大學碩士論文, 2002.

27. 蔡大進等,表面聲波氣體感測器之研究與應用, 2003.

1. Lord Rayleigh, “On waves propagating along the plane surface of an elastic solid”, Proc. London Math. Soc., Vol.17, pp.4-11, 1885.

2. R. M. White and F. M. Voltmer, “Direct piezoelectric coupling to surface elastic waves”, Appl. Phys. Lett., Vol.7, pp.314-316, 1965.

3. A. Viktorov, Rayleigh and Lamb Waves, Plenum, New York, 1967.