本論文設計了一個CMOS整合式單軸壓阻式加速度計，使用多晶矽作為壓阻，並且在符合Design Rule以及後製程需求的前提下盡可能降低懸臂樑的厚度以及寬度，從而使懸臂樑接收更大應力以增加感測度。並且在後製程的步驟中皆是使用濕蝕刻，能夠降低成本及複雜度。同時，CMOS整合可以帶來降低成本以及整合感測電路等優點，在結構尺寸縮小的同時保障高感測度。結構的尺寸上也測試了三種不同的質量塊尺寸，可對應至不同的應用場合。
本研究使用TSMC 0.35μm two-polysilicon-four-metal (2P4M) CMOS標準製程，晶片的大小為2.41 mm × 2.41 mm，經過一系列的後製程，實現單軸壓阻式加速度計，以達成與CMOS標準製程的高整合。三種結構主要是質量塊的尺寸不同，分別為200 μm × 200 μm、150 μm × 150 μm、100 μm × 100 μm。經過量測，共振頻率分別為2260 Hz、4015 Hz、8125 Hz。感測度分別為317.72 μV/g/V、96.71 μV/g/V、38.57 μV/g/V。溫度對於感測度的變化分別為-2.604 μV/g/V/ºC、-0.659 μV/g/V/ºC、-0.299 μV/g/V/ºC。加速度的解析度分別為18.125 mg、42.999 mg、117.46 mg。

This paper designs a CMOS integrated uniaxial piezoresistive accelerometer, using polysilicon as the piezoresistor. The thickness and width of the cantilever beam are minimized as much as possible in compliance with the Design Rule and post-processing requirements. This allows the cantilever beam to receive greater stress and enhances sensitivity. All the steps in the post-processing use wet etching, which can reduce cost and complexity. Simultaneously, CMOS integration brings advantages such as cost reduction and integrated sensing circuitry, ensuring high sensitivity while minimizing structural dimensions. Our study also tests three different mass block sizes, which can correspond to different application scenarios.
This study uses the TSMC 0.35μm two-polysilicon-four-metal (2P4M) CMOS standard process, and the size of the chip is 2.41 mm × 2.41 mm. After a series of post-processing steps, a single-axis piezoresistive accelerometer is realized, achieving high integration with the CMOS standard process. The three structures mainly differ in the size of the mass blocks, which are respectively 200 μm × 200 μm, 150 μm × 150 μm, and 100 μm × 100 μm. After measurement, the resonant frequencies are respectively 2260 Hz, 4015 Hz, and 8125 Hz. The sensitivities are respectively 317.72 μV/g/V, 96.71 μV/g/V, and 38.57 μV/g/V. The temperature changes with respect to sensitivity are respectively -2.604 μV/g/V/ºC, -0.659 μV/g/V/ºC, and -0.299 μV/g/V/ºC. The resolution of acceleration is respectively 18.125 mg, 42.999 mg, and 117.46 mg.

摘要 I
Abstract II
誌謝 III
目錄 IV
圖目錄 VI
表目錄 XI
第一章 緒論 1
1-1 前言 1
1-2 微加速度計的發展及應用 2
1-3 文獻回顧 2
1-3-1 壓電式加速度計 3
1-3-2 電容式加速度計 3
1-3-3 壓阻式加速度計 4
1-3-4 熱感應式加速度計 4
1-4 研究動機 6
第二章 加速度計設計與模擬 7
2-1 加速度計感測架構 7
2-2 加速度計結構設計 9
2-3 感測器結構模擬 14
2-3-1 共振模態模擬 14
2-3-2 懸臂樑應力及位移模擬 19
2-3-3 壓阻阻值變化模擬 23
2-4 感測器電路模擬 27
2-5 感測度推算 31
第三章 加速度計實現及後製程 33
3-1 佈局考量 33
3-2 後製程施作 40
3-3 電路板設計 47
第四章 量測結果與討論 49
4-1 結構量測 49
4-1-1 三維微觀量測 49
4-1-2 結構振頻量測 53
4-2 電路量測 56
4-3 加速度量測 59
4-3-1 感測度量測 60
4-3-2 溫度對感測度影響之量測 66
4-4 噪聲量測 73
4-4-1 頻譜噪聲量測 73
4-4-2 Allan方差量測 77
第五章 結論與未來 80
5-1 研究成果 80
5-2 未來工作 82
參考文獻 83

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