表面微細加工（surface micromachining）是微機電系統（MEMS）中最重要的製造技術之一；它是利用半導體製程之薄膜沈積與蝕刻等相關技術，以矽晶片為基底（substrate），進行微結構的製作。其中，薄膜的機械性質會隨著製程條件而改變，不再像一般巨觀尺度下可視為定值。因此，如何得知結構實際的機械性質，就成為設計微結構時的重要課題。
本研究的目的在於設計一套簡便且準確方法來量測polysilicon的楊氏係數。主要以靜電驅動式微懸臂樑作為測試樣本，使用Vertical Scanning Interferometry的方式，量測樣本的吸附電壓（pull-in voltage）與變形量，最後藉由有限元素分析軟體ANSYS，進行靜電結構分析，以求取薄膜的實際E值。
在實驗過程中，我們以49%HF進行犧牲層之蝕刻，並成功的使微結構達到懸浮，其蝕刻時間約為65～70秒。另外，本文所使用的分析方式經證明可有效模擬微結構的靜電效應。

Surface micromachining is one of the most important manufacturing technologies in MEMS. It uses thin film deposition and etching technologies to fabricate microstructure. The mechanical properties of thin-films will change during process, and can’t be considered as constants as in macro-mechanics. Thus, how to measure the mechanical properties precisely is very important for microstructure design.
The objective of this study is to develop a simple and accurate method to predict Young’s modulus of polysilicon. The approach is to measure the pull-in voltage and deflection by using electrostatic-actuated cantilever beams. Substitute all the data into ANSYS and Young’s modulus of polysilicon can be obtained.
After release, the structure has suspended successfully. In addition, the analysis method presented in this thesis can simulate the electrostatic effect efficiently.

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