有限元素模型在小型化石英振盪器改善干擾頻之設計分析

The Design and Analysis to Improve Spurious Frequency on Miniature Quartz Resonators Using the FEM Model

洪聖傑(Sheng-Jie Hong)

指導教授 ： 黃自貴

國立虎尾科技大學/工程學院/機械設計工程研究所/碩士(2013年)

https://doi.org/10.6827/NFU.2013.00075

摘要

隨著科學技術的迅猛發展，國內外石英振盪器性能優異，類型繁多，應用領域廣泛，皆遠非昔日可比。廣泛的應用領域，如長途和市話通訊，地面、航海和航空移動目標通訊，衛星雷達通訊，手錶手機運用等等。石英振盪器具有壓電效應，給予石英平板電極時，能產生激振振盪。石英晶體為異向性材料，因此不同的切割方式會產生不同的材料特性。但振盪過程中，出現不良的激振造成干擾頻影響基頻振盪，本研究主要藉由石英平板模型改良，改善干擾頻的不良振盪。
本研究針對於AT切面的石英晶體薄板振盪下所產的干擾頻進行改善。從二維模型中，將石英晶體薄板中間減薄、石英晶體薄板角落倒圓角與倒角 進行分析後，得知倒角 消除干擾頻效果最佳。再進一步三維模型中，針對二維倒角 模型三維化，增加 至 倒角模型進行分析。並且增加石英晶體薄板長度與寬度變化之效應。最後分析三維石英晶體薄板中加載金屬電極效應探討與分析。

關鍵字

石英振盪器 ； AT-cut ； 干擾頻 ； 基頻 ； 金屬電極效應

並列摘要

With the rapid development of science and technology, domestic and quartz oscillator performance, type of variety, wide range of applications, are far from comparable past. Wide range of applications, such as long-distance and local telephone communications, terrestrial, marine and aeronautical mobile target communications, radar, satellite communications, watch mobile phone use and so on. Quartz oscillator has a piezoelectric effect, giving quartz plate electrode, can generate excitation oscillation. Quartz crystal is anisotropic materials, so different cutting methods will produce different material properties. The oscillation process, adverse impact excitation cause spurious baseband frequency oscillation, this study mainly by quartz plate model improvement, improving poor oscillation frequency spurious.
Keyword : Quartz resonator、AT-cut、thickness shear mode、excitation vibration、dead vibration、temperature effect
This study of AT-cut quartz crystal plate oscillation frequency spurious produced under improvement. From the two-dimensional model, the intermediate thinning quartz plate, quartz crystal plate with chamfered corners rounded analysis, we find that the best results chamfered to eliminate spurious frequency. Further three-dimensional model, the three-dimensional model of the two-dimensional bevel, chamfer increased to model analysis. Quartz crystal plate and increase the length and width of the effects of changes. Final analysis of three-dimensional crystal thin metal electrode effect loaded discussion and analysis.

並列關鍵字

Quartz oscillator ； AT-cut ； spurious frequency ； baseband ； metal electrode effect

參考文獻

1.黃自貴,陳政宇,2011, “二維有限元素模型在小型化石英振盪器之設計分析”, 國立虎尾科技大學機械設計工程系碩士論文

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