- 學位論文
頻閃白光干渉儀應用在微元件之動態分析
Development of Detecting Dynamic Characteristic in MEMS Using Stroboscopic Interferometry
摘要
本論文旨在發展白光干涉顯微量測系統，並加入一微機電元件之干涉動態量測方法，包含主動式與非主動式自然頻率動態量測功能，以建構一完整之動、靜態干涉顯微量測系統，應用於微動件或其他生醫元件之模態表徵與動態特性量測。主動式共振頻率掃描主要是給定樣品一與頻閃光源同步的弦波訊號源，並驅動受測樣品產生振動，在藉由系統量測物體之共振頻譜。而非主動式共振頻率掃描之特點為振動樣品之驅動源為一待求未知之參數，與頻閃光源不同歩之信號，當樣品之自然頻率在此一信號之頻寬範圍內，則樣品產生振動，此時利用非主動式共振頻率掃描得到樣品之共振頻率。 在動態三維輪廓量測中，本系統是使用頻閃法來獲得動態物體之表面輪廓，但當頻閃光源之工作週率過大時會造成干涉條紋影像之對比下降；由於系統所攫取到之干涉訊號是與光源訊號褶積後之訊號對比下降結果，為解決此對比下降之問題，本研究利用訊號處理之方式，使用反褶積的方法來增強原本訊號對比下降之白光干涉訊號。 本研究已研製出一套閃頻式光干涉顯微動態量測儀之實驗系統，具備全域式動、靜態表面輪廓量測以及主動式與非主動式微元件之共振頻率量測之功能。
並列摘要
A dynamic 3-D profilometer with nano-scale measurement resolution was successfully developed using stroboscopic illumination and white-light vertical scanning techniques. In view of this need, previous theory of various optical interferometric systems and technologies for dynamic 3-D surface profilometry were carefully investigated. Furthermore, a microscopic prototype based on white-light stroboscopic interferometry using vertical scanning principle was developed to achieve dynamic full-field profilometry and characterization of MEMS devices. In this project, an innovative method of automatic resonant mode detection employing non-conventional stroboscopic interferometry was successfully developed for nano-scale dynamic characterization of microstructures. Considering that a tested microstructure having an individual vibrating excitation source cannot be analyzed directly by the traditional stroboscopic method, an optical microscopy based on new stroboscopic interferometry was established to achieve resonant mode detection and full-field vibratory out-of-plane surface profilometry of microstructures. An AFM micro cantilever beam was measured to verify the system capability. We also employed ANSYS to perform the dynamic simulation analysis of the theory. Some experimental results have indicated that the developed method is capable of detecting passive-type resonant frequency of MEMS. In view of this need, a novel deconvolution algorithm using correction of the light response was established to remove the potential image blurs caused by the unavoidable vibration of the tested parts. With this technical advance, the bandwidth of dynamic measurement can be significantly increased without sacrificing measurement accuracy.