本文內容主旨是在研究矽基材料受到外力撞擊時之動態反應，配合有限元素模型模擬整個歷程，再將實驗結果分析並與有限元素模型比較。文中所用之感測器其材料為壓阻材料(poly-silicon)，以微製程將其直接製作於矽基材料上作為感測器，利用落錘方式撞擊矽基材料作低速撞擊實驗，由感測器量取應力波速度與應力值，同時檢驗感測器的正確性與適用性。
　　本論文主要是利用一維應力波理論來分析當材料受到撞擊時應力波之速度與接觸時間之狀況，將衝壓系統微小化並配合有限元素模型將撞擊歷程加以模擬，對矽基材料受到撞擊之行為進行分析，最後將實驗結果與數值結果作一互相比較，發現兩者在低速撞擊時第一次通過應變計之應力波應力值與理論與數值模擬值極為相符，誤差小於5%；而在波速的量測上也有相當的正確性，誤差小於10%；在相同製程下也提供了應變計參數上的參考值。

　　The purpose of this work is to study the dynamic material response of silicon wafer subjected to low-velocity impact loading. Transient finite element analysis is used to check the experimental result against the numerical solution. Good relationship between each other is observed. The micro-sensor is made of poly-silicon material utilizing the microfabrication techniques. A series of low-velocity impact experiment using the home-made drop-weight mini-tower tester are conducted. These tests are used to examine the accuracy and adequacy of the current poly-silicon strain sensor for stress-wave propagation application measurement.
　　In this thesis, we also use the one-dimensional wave propagation theory to compute the longitudinal wave speed and the contact stress level when the mini beam-type silicon substrate suffers an impact loading. It is concluded that present experimental results of measuring wave speed and stress level are correspond with either theoretical wave speed and stress level or numerical solution. The inaccuracy of wave speed is less than 10 percent and the inaccuracy of stress level will less than 5 percent. We also provide the gauge factor for consultation with the same fabrication.

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