隨著近年工業物聯網(Industrial Internet of Things，IIoT)快速發展，使全球製造業開始往高度自動化及智慧化轉型，因此對於感測器的需求逐漸增加，其中加速規(accelerometer)為被廣泛應用於監控設備運作的慣性運動感測器，因此該元件的開發非常重要。而眾多種類的加速規當中又以MEMS無鉛壓電加速規具有低功耗、體積小、使用環保材料、高性能等多項優點，因此本研究著手進行開發無鉛壓電材料與MEMS無鉛壓電加速規等壓電材料與元件兩大項目。
材料開發的部分為採用Mo摻雜來提升AlN薄膜的壓電特性，並且透過EDS、XRD、SEM、AFM、PFM等材料分析來探討壓電特性優化的機制與找尋最佳製程參數，其中以AlN:Mo(3.46%)為最佳參數，該材料的壓電係數d33達到7.33pm/V，與未摻雜的AlN相比提升了82.79%，並且產生了鐵電特性，其殘留極化量Pr為0.319 μC /cm2。
元件開發的部分為設計一款可同時應用於低頻與高頻環境感測的方形MEMS無鉛壓電加速規，透過結構公式與ANSYS軟體模擬該元件的振動模態與共振頻率來進行結構設計，以及採用MEMS製程完成元件的製作，該元件的共振頻率為1740Hz、Z軸靈敏度為1.96mV/g、橫向靈敏度比為0.6%。並且成功實際應用於低頻機械手臂與高頻渦輪幫浦等機台運作狀態感測。

This study uses Mo doping to improve the piezoelectric properties of AlN film, and through material analysis to explore the mechanism of piezoelectric properties optimization and find the best process parameters. Among them, AlN:Mo (3.46%) is the best parameter. The piezoelectric coefficient d33 reaches 7.33 pm/V, which is 82.79% higher than that of undoped AlN, and it has ferroelectric characteristics, and its residual polarization Pr is 0.319 μC/cm2.
This study also designed a square MEMS lead-free piezoelectric accelerometer that can be used for both low-frequency and high-frequency environmental sensing. The structural formula and ANSYS software are used to simulate the vibration mode and resonance frequency of the device for structural design, and the use of MEMS The process completes the production of the device. The performance of square MEMS piezoelectric accelerometer is that the resonance frequency is 1740Hz (The simulation error is only 3.3%), the Z-axis sensitivity is 1.96mV/g, and the transverse sensitivity ratio is 0.6%. And successfully applied to low-frequency robotic arm and high-frequency turbo pump and other machine operating status sensing.

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