當今隨著「工業4.0」概念的提出，智慧工廠（Intelligent Plant）、智慧機械（Intelligent Machine）與全球物聯網（Internet of Things, IoT）系統也迅速發展，加速規也扮演著其中重要的一環。MEMS壓電式三軸加速規具有小、輕、應用範圍非常廣等優點，其中壓電材料中的PZT具有高壓電係數、高介電常數、低損耗等優點，因此常被用於製作壓電式元件。
於本論文中，我們利用溶膠凝膠法，並將壓電厚膜應用於微機電系統(Micro Electro Mechanical Systems, MEMS)加速規。加速規的好壞取決於靈敏度大小，本研究將探討材料影響元件靈敏度的各種參數，並針對結構做設計、模擬和優化，再到最後的MEMS製程，並在其中帶入一些數學模型，同時兼具材料、設計、模擬、製程、優化、驗證等流程。
本研究發現，材料影響靈敏度的重點為材料的(d∙E)/ε值，在Pb過量20%和Nb 摻雜1%時有著最好的乘積，以此材料參數代入ANSYS做模擬和設計。經過一些數學模型的推導和參考，最後設計出一個在期望頻寬內高靈敏度和低軸相干擾的MEMS三軸壓電式加速規，且以新的指叉形當作電極圖案。加速規模擬出來之三軸共振頻率分別為(X, Y, Z) = (12.6, 31.6, 11.8)kHz，靈敏度為(X, Y, Z) = (6.11, 5.44, 8.85)mV/g，且有著低於15%的軸相干擾。

In this research, PZT piezoelectric thick films were fabricated using the sol-gel method and applied to MEMS accelerometers. Our findings indicate that the key material parameter affecting sensitivity is (d∙E)/ε, where the optimal value was achieved with 20% Pb excess and 1% Nb doping. These material parameters were used in ANSYS simulations for device modeling and design. Based on theoretical derivations and simulations, we designed a triaxial piezoelectric MEMS accelerometer with high sensitivity and low cross-axis interference within the target frequency bandwidth, employing a novel interdigitated electrode (IDE) pattern.The simulated resonant frequencies of the three axes were (X, Y, Z) = (12.6, 31.6, 11.8) kHz, and the corresponding sensitivities were (6.11, 5.44, 8.85) mV/g. The cross-axis interference was less than 15%, demonstrating the effectiveness of the proposed design.

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