隨著微機電系統科技的發展，微小裝置（如微感測器（micro-sensor）、微型致動器（micro-actuator）等）的製作需確定其可靠度及其使用壽命，才能將之運用於實際場合。由於微型結構的材料機械性質（如強度、楊氏係數（Young’s modulus）、浦松比（Poisson ratio）…等）受到製程的參數影響，不同的製作參數，製作的結構將表現出不同的機械性質，故在作微結構之設計時，不能以相同材料在大尺寸下之機械性質為設計參數，需瞭解在微小尺寸下之機械性質後方可運用，故需對於微小試件進行研究及實驗。

　　目前的微機電或微光機電系統及其組件之製作，通常都含有多種材料或材料的組合而成，以具體展現出感測或致動上所需的各種功能。由於微結構的材料行為會明顯的受到製程技術的影響，微結構的材料性質不能直接由大尺寸試件的結果依比例推算而來，因此，必須直接對微小試件作測試，以了解其在承受負載時之機械行為。

　　由於單軸向拉伸之力學模型最為單純，也最為準確，故本文利用單軸向拉伸試驗，將試件外型設計為一狗骨頭狀，並設計一夾頭及六軸位置微調機構，可輕易將微小試件精確定位並夾持固定，並以壓電致動器（Piezo）對試件進行拉伸，再以測力計（Load Cell）量得試件之受力，以圖控式控制軟體（Labview）將其整合，成為一自動量測系統，可自動操作實驗儀器並紀錄實驗數據，再自動計算出微結構之機械性質。

　　為進一步得知微結構之動態性質，將試件製成懸臂樑之模式，以訊號產生器（Function Generator）控制一激振器（Shaker）對試件進行激振，再以電子斑點干涉術（ESPI）之光學量測方法配合顯微鏡對微結構之動態性質進行分析及量測，其自然頻率及振動模態與理論值相比較，誤差低於10%，為可接受之誤差範圍。

　Along with the development in MEMS technology, the mechanical properties of miniature materials should be confirmed to insure the reliability and durability. The mechanical properties of micro-structures affect the performance and reliability of MEMS devices such as micro sensors and actuators. Understanding the mechanical behaviors by directly testing the micro samples becomes indispensable The performance of miniature materials is different from that in large size. The main theme of this paper is to develop a measurement system to measure the mechanical properties such as elastic tensile property, Poisson ratio, natural frequencies, and mode shapes of miniature materials. We present an automatic uni-axial tensile testing system to measure the mechanical properties of a miniature specimen that was developed. The tensile specimens are “dog-bone” shaped of different sizes and ending in a large “paddle” for convenient gripping by the tester. By employing the PZT actuator and the load cell, the system records the force-displacement history and automatically evaluates the Young’s modulus of the specimen under test. Application of the system to test various sizes of specimens is demonstrated. The bending stress caused by the active force location on specimen is easily ignored. This could cause large experimental error. The size effect of mechanical properties on miniature specimen is found. This research provides a method of measuring the mechanical properties of copper and silicon thin film and indicates some factors such as loading position that should be noted.

　Additionally, we provided a real time optical measurement method to evaluate the natural frequency, mode shape, and Young’s modulus of miniature specimen. The method was carried out using Electronic Speckle Pattern Interferometry (ESPI), which could be applied to detect the natural frequencies and to visualize the mode shapes of vibrating object. In addition, the Young’s modulus was determined by experiment results. ESPI is convenient to study small and weak objects because of non-contact and full field. It was successfully applied to study cantilever micro-beams. Measured results are agreement well with theoretical solutions, error less than 10%, and lead to the determination of Young’s modulus of miniature specimens.

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