氣膠沉積法應用於微型壓電揚聲器之開發與設計

The Development and Design of Piezoelectric Micro Speakers Based on Aerosol Deposition Method

許程翔(Cheng-Hsiang Hsu)

指導教授 ： 吳文中

國立臺灣大學/工學院/工程科學及海洋工程學研究所/碩士(2021年)

https://doi.org/10.6342/NTU202100470

摘要

隨著科技的日新月異，消費性電子產品逐漸盛行，其中包含了智慧型攜帶裝置如手機及平板，甚至到尺寸更小的耳機、助聽器等，除此之外，通訊軟體及相關產業也隨其蓬勃發展，使得人與人之間透過電子產品的溝通逐漸頻繁。而現今電子產品有微小化的趨勢，微小化除了可以降低功耗以外，同時具備低成本、可大量生產以及重量輕等優勢，因此市場對於低功耗、體積小的微型揚聲器的需求日益提升。
本研究以設計低功耗之微型壓電揚聲器為目標，沿用本奈米生醫微機電實驗室過去所研發的氣膠沉積法作為壓電層的沉積方法，輔以不鏽鋼框進行10微米不鏽鋼基板之高品質壓電厚膜金屬微機電(Metal-MEMS)製程，製作出以不鏽鋼為基材之微型壓電揚聲器。本研究採用壓電致動器推拉振膜的結構，設計出不同形狀的壓電層鋪設圖形之揚聲器並探究其輸出表現上的差異。
經由實際量測，在自由音場之表現方面，本研究之壓電圖形內縮設計雖然會降低整體聲壓的輸出，但是足以讓低頻之聲壓提升;在封閉音場之表現方面，此壓電圖形內縮設計之揚聲器在低頻段之輸出優於未內縮設計之揚聲器。

關鍵字

微型壓電揚聲器 ； 金屬微機電製程 ； 氣膠沉積法 ； 不鏽鋼

並列摘要

With the rapid development of technology, consumer electronics have gradually become popular causing the rise of smart portable devices such as mobile phones, tablets or even smaller-scaled devices like earphones and hearing aids, etc. Communication software and related industries are booming, making communication between people through electronic products more frequent. Nowadays, electronic products are gradually miniaturized. In addition to reducing power consumption, miniaturization also has the advantages of low cost, mass production, and light weight. Therefore, the market demand for small and low-power micro speakers is increasing.
The goal of this research is to design low-power micro piezoelectric speakers based on aerosol deposition method developed in the past by Nano-Bio MEMS laboratory. The design is fabricated with high quality PZT thick-film Metal-MEMS process on 10-micrometer-thicked stainless steel-framed substrate. In this research, a piezoelectric actuator is used to push and pull the diaphragm. This research also shows the design of speakers with different shapes and patterns of piezoelectric layers and discusses the differences between their output performances.
The measurement of the sound pressure in the free field reveals that although the piezoelectric layer graphic design reduces the overall sound pressure output, it can still increase the sound pressure in the low frequency region; and as for in the enclosed field, the deigned PZT layer also shows a better performance of output in the low frequency region.

並列關鍵字

piezoelectric micro speaker ； Metal-MEMS ； aerosol deposition method ； stainless steel

參考文獻

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