陣列式垂直整合感測電極之CMOS-MEMS電容式觸覺感測器

Array-type Vertically Integrated Electrode Design for CMOS-MEMS Capacitive Tactile Force Sensor

謝孟霖(Meng-Lin Hsieh)

指導教授 ： 方維倫

國立清華大學/工學院/動力機械工程學系/碩士(2020年)

摘要

觸覺感測器的應用十分廣泛，於電子產業、機器人產業、與醫療產業中皆有龐大的應用商機。從目前觸覺感測器的文獻回顧中可見，廣泛使用的電容式觸覺感測器於設計時，許多團隊之研究使用各類方式，試圖提升元件的感測靈敏度。因此，本研究希望利用半導體的商用標準製程平台 (TSMC 0.18µm 1P6M) 的多重優勢，包括彈性的結構設計、多層的薄膜堆疊、次微米的線寬、強大的電性串聯能力，並透過結構設計來提升電容式觸覺感測器的靈敏度。在本研究中，垂直堆疊感測的電極在將間隙填入polydimethylsiloxane (PDMS) 後，可在相同的面積使用量下提升觸覺感測器的靈敏度。並且，故透過減小薄膜並陣列化之設計，可以大幅減少翹曲量所造成之問題。本研究將以陣列化之兩層電極堆疊之比較組以及三層電極堆疊之設計組，證實垂直整合感測電極對於元件性能之提升，約30% 的靈敏度提升 (4.28至5.46 fF/N)。另外，將對於陣列化後的電極進行翹曲以及受力之量測，來證實對翹曲之抑制。最後，由於研究中所使用的高分子材料所可能受溫度的影響，故元件亦在不同溫度下進行定量的性能分析。

關鍵字

CMOS-MEMS ； 電容式感測 ； 觸覺感測器 ； 垂直整合電極

並列摘要

Tactile sensors have a wide range of commercial applications, which include uses in the consumer electronics, robotics, and medical industry and many research is focused on improving sensitivity performance. Similarly, this study aims to leverage many benefits of the standard commercial semiconductor fabricating platform (TSMC 0.18µm 1P6M), to develop a capacitive tactile sensor for the enhancement of sensitivity through structural designs. In this research, the vertically integrated electrodes combined with the molded polydimethylsiloxane (PDMS) can enhance the sensitivity of the tactile sensor. However, the tactile sensor fabricated by the CMOS platform may suffer from problems arising for the warpage introduced by residual stress, therefore sensing membranes are reduced in size and arrayed to effectively reduce warpage issues. In this research, a reference type with two layers of sensing electrodes, and a design type with three vertically integrated electrodes were fabricated, and the sensitivity was enhanced by approximately 30% (from 4.28 to 5.46 fF/N). Furthermore, warpage by residual stress was inhibited by the reduction in sensor size. Lastly, due to the employment of polymer, quantitative analysis for the sensor under different working temperatures were conducted.

並列關鍵字

CMOS-MEMS ； capacitive ； tactile sensor ； vertical integration

參考文獻

[1] Apple Inc, “Earbuds with capacitive touch sensor”, United States Patent 10 003 881, June 19, 2018.

[2] M.H. Lee, “Tactile Sensing: New Directions, New Challenges,” The International Journal of Robotics Research, vol. 19, no.7 pp. 636-643, 2000.

[3] R.S. Dahiya and Maurizio Valle, Robotic Tactile Sensing, New York, Springer, 2013, pp. 9.

[4] Credence Research, Tactile Sensor Market Size, Share, Trend and Forecast to 2026, March 2019. Accessed on: November 11, 2019. [Online]. Available: http://www.credenceresearch.com/report/tactile-sensor-market.

[5] IndustryArc Analysis, Tactile Sensor Market – Forecast (2019-2014), July 10, 2018. Accessed on: November 11, 2019. [Online]. Available: http://industryarc.com/Report/16968/tactile-sensor-market.html.