可抵抗製程變異之高靈敏度電容式觸覺感測器

Design of a Highly Sensitive Capacitive Tactile Sensor with Compensation of Process Variations

吳典耕(Tien-Keng Wu)

指導教授 ： 蔡宗亨

國立中正大學/工學院/電機工程學系/碩士(2013年)

摘要

本論文實現一個高靈敏度電容式指紋感測器與一個機器人觸覺感測器，機器人觸覺感測器搭配感測電路去讀取感測器接收到的壓力訊號。這兩個感測器皆使用TSMC 0.35µm CMOS製程進行製作。為了讓電容式指紋感測器能夠取得清楚的指紋影像，利用CMOS製程中的Passivation層製作T型突出物於感測薄膜的表面，突出物能夠傳遞手指的力量到感測薄膜上，使得指紋感測器擁有高的靈敏度特性。兩種感測器皆由CMOS製程中的金屬層與介電層堆疊組合而成，並不需要額外的薄膜沉積，只需幾道簡單的後製程步驟即可完成。以全差動的相關雙取樣電容電壓轉換器做為感測電路，利用參考電容校正的機制來有效抵抗製程變異，大幅增加感測器對於製程變異的容忍度，感測電路的靈敏度為18mV/fF。

關鍵字

觸覺感測器 ； 微機電系統 ； 感測電路

並列摘要

This thesis presents a highly sensitive capacitive fingerprint sensor and a robotic tactile sensor with sensing circuit. Sensing circuit of the robotic tactile sensor is able to read pressure signal. Both of the sensors are fabricated by a TSMC 0.35µm CMOS technology. In order to detect clear fingerprint images, T-shaped protrusion is fabricated by the passivation layer in CMOS technology on the sensing membrane. The T-shaped protrusion is able to propagate force from the finger to sensing membrane. It makes the fingerprint sensor highly sensitive. Both of the sensors are constituted by the metal layer and the dielectric layer without extra thin film deposition, and can be completed with few simple post-processing steps. With the fully differential correlated double sampling capacitor-to-voltage converter (CDS-CVC) and reference capacitor correction, process variation is compensated. The sensitivity of the sensing circuit is 18mV/fF.

並列關鍵字

sensing circuit ； tactile sensor ； MEMS

參考文獻

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