CMOS 微靜電力掃描探針之設計與製作

Design and Fabrication of CMOS micromachined cantilevers for Electrostatic Force Microscopy

洪士傑(Shi-Jie Hung)

指導教授 ： 盧向成

國立清華大學/電機資訊學院/電子工程研究所/碩士(2007年)

摘要

本研究目的在於製作新型非接觸振動式微探針靜電力掃描，而目標將設定在以微機電技術設計並製造新穎、具高性能的靜電力微探針，並結合CMOS積電電路製程完成整合型感測器晶片。希望藉由直接電路整合降低寄生電容所帶來的訊號衰減及電路噪聲放大。利用不同的靜電力使懸臂樑的自然頻率偏移，期望達到微小化且能精確感測微靜電力的新型感測器。
本論文將介紹以懸臂樑為結構之CMOS MEMS 微靜電感測器的設計概念、製作流程以及其特性分析與量測結果探討。我們設計以CMOS標準製程製作整合型晶片，在CMOS晶片上以乾蝕刻釋放金屬鋁及介電質二氧化矽兩材料堆疊之懸臂樑。以驅動電極驅動懸臂樑，並於上電極板施加調制訊號源將驅動頻率調制到高頻，以達到降低雜訊的優點。而電容式感電路能直接量測懸臂樑的頻率響應，以便找出結構共振頻率。我們成功的量測到約18KHz的結構共振頻率，並在不同的靜電力下，得到頻率響應的變化與品質因子的變化。
本研究論文很重要的意義在於設計製造符合標準製程，也因此更有機會結合其他應用而量產應用於市場。

關鍵字

靜電力掃描 ； 懸臂樑 ； 電容式感測 ； CMOS MEMS

並列摘要

In this thesis, we present the design, fabrication, and characterization of CMOS micromachined cantilevers for noncontact electrostatic force microscopy (EFM). The cantilevers consisting of multiple metal and dielectric layers are fabricated after completion of the convention CMOS process by dry etching steps. The cantilevers are electrostatically actuated to resonance in the out-of-plane direction. The frequency shift due to different electrostatic force is detected capacitively with on-chip circuitry, in which the modulation technique is used to eliminate the capacitive feedthrough from the driving port, and to lessen the effect of flicker noise. The resonant frequency of the cantilever is measured at about 18 KHz and the quality factor of 12.71 with different electrostatic force.
The important purpose of this thesis is that the design and fabrication can be realized in a to the convention CMOS process.

並列關鍵字

Electrostatic Force Microscopy (EFM) ； Cantilever ； Capacitive sensing ； CMOS MEMS

參考文獻

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