在本論文中，透過現有之TSMC 0.35μm CMOS製程實現了CMOS-MEMS共振閘極電晶體(RGFET)，與現有傳統的電容式微機電共振器相比較，RGFET透過電晶體固有的增益，可以進一步放大共振器的運動電流訊號。在共振閘極部分採取了雙端固定樑的設計，並且與浮閘式電晶體結合形成RGFET，如此的設計可以同時得到具有高品質因數的共振器與高W/L值的元件。透過對元件的行為理解並推導出其模型，此外，我們亦設計適當的製程流程以得到次微米空氣間隙，將共振器的運動阻抗降低到10 kΩ。
為了達到微機電震盪器的設計，利用同樣的製程平台，將元件改成陣列式架構以降低運動阻抗，在陣列設計的助益下，共振器的運動阻抗降低到5 kΩ，同時其power handling亦得到改善，使所形成的震盪器在遠端相位雜訊有了相當好的呈現。在陣列式雙端固定樑的設計中，我們採取了高剛性機械組合樑，以確保陣列設計可以得到最大的效益，此外，我們亦將固有的增益模型，從單根推展至陣列的型態，其等效震盪器電路模型也一併呈現。從實驗的量測結果來看，陣列的設計除了可以實現Pierce震盪器，也直接的改善了相位雜訊。
在本論文的最後，我們提出了利用電洞能帶穿隧的充電方法，取代之前所使用的手動充電方法，此方法可以提供元件一個更加長效穩定的操作偏壓。同時，我們更進一步改善元件整體設計，同時從機械結構以及電晶體著手，實驗量測結果得知，此共振器具有品質因數1,800以及目前領域中最低的運動阻抗1.1 kΩ。在各特性都獲得改善的情形下，其所形成的微機電震盪器，其相位雜訊呈現可以分別在近端達到-96 dBc/Hz和遠端的-122 dBc/Hz。

A charge-biased CMOS-MEMS resonant gate field effect transistor (RGFET) composed of a metal/oxide composite resonant-gate structure and an FET transducer has been demonstrated utilizing the TSMC 0.35 μm CMOS technology. As compared to the conventional capacitive-type MEMS resonators, the proposed CMOS-MEMS RGFET features an inherent transconductance gain (gm) offered by the FET transduction capable of enhancing the motional signal of the resonator and relaxing the impedance mismatch issue to its succeeding electronics or 50 Ω-based test facilities. In this work, we design a clamped-clamped beam (CC-beam) resonant-gate structure right above a floating gate FET transducer as a high-Q building block through a maskless post-CMOS process to combine merits from the large capacitive transduction areas of the wide-width beam resonator and the high gain of the underneath FET. An analytical model is also provided to simulate the behavior of the charge-biased RGFET. Thanks to the deep-submicron gap spacing enabled by the post-CMOS polysilicon release process, the proposed resonator under a purely capacitive transduction already attains the motional impedance less than 10 kΩ.
To further improve the performance of RGFET, the arrayed RGFET is proposed. A CMOS-MEMS arrayed RGFET fabricated by a standard 0.35 μm CMOS-MEMS platform is implemented to enable a Pierce-type oscillator. The proposed arrayed RGFET exhibits low motional impedance of only 5 kΩ and decent power handling capability. With such features, the implemented oscillator shows impressive phase noise of -117 dBc/Hz at the far-from-carrier offset (1 MHz). In this work, we design a clamped-clamped beam (CCB) arrayed resonator utilizing a high-velocity mechanical coupling scheme to serve as the resonant-gate array. To understand the behavior of the proposed arrayed device, an equivalent circuit model consisting of the resonant unit and FET is also provided. To verify the effects of the post-CMOS process on device performance, a conventional MOS ID current measurement is carried out. Finally, a CMOS-MEMS arrayed RGFET oscillator is realized by utilizing a Pierce oscillator architecture, showing decent phase noise performance that benefits from the array design to alleviate the nonlinear effect of the resonant gate.
In the end, a novel band-to-band tunneling bias scheme is employed for the proposed CMOS-MEMS RGFET without the need of manual switch charging or complicated biasing circuits. With the mechanically coupled array approach and deep submicron gap spacing, the proposed resonator with Q of 1,800 under purely capacitive transduction achieves the record-low motional impedance Rm of 1.1 kΩ among all CMOS-MEMS resonators. By using the FET readout, a CMOS-MEMS arrayed RGFET oscillator is realized through a closed-loop configure uration, demonstrating phase noise performance of -96 dBc/Hz at 1 kHz offset and -122 dBc/Hz at far-from-carrier offset, respectively.

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