本研究開發三維奈米碳管與高分子整合製程，及利用此製程及設計製作撓性電容式感測元件，分別為應變感測，彎曲曲率感測，觸覺感測及近接感測。此研究利用奈米碳管結合高分子的複合材料當作電容式的指叉電極，因奈米碳管成長高度約為50 ~100□m，故會有較大的感測面積及感測電容值。另外透過在矽基材上成長不同的三維奈米碳管的圖形分佈，再藉由簡單的高分子翻膜技術，便可以製作出三維奈米碳管結合高分子材料的感測電極和電路，並以高分子材料當做電容感測器的基材增加其可撓性。相較於金屬電極沉積在高分子基材上，利用奈米碳管結合高分子的複合材料，可以避免感測電極和高分子基材黏著性不佳的問題。本研究成功利用本文開發之製程平台，實現多種撓性電容式感測元件，並且對於應變感測，彎曲曲率感測，觸覺感測及近接感測進行性能的分析及探討，最後整合觸覺感測和近接感測。未來可朝向陣列式的發展，並將感測電路和控制系統做整合，應用於機械手臂及穿戴式智慧裝置系統。

This study reports a novel approach to implement 3D carbon nanotubes (CNTs) interdigitated finger electrodes on flexible polymer, and the detection of strain, bending curvature, tactile force, and proximity distance are demonstrated. The merits of presented design are as follows, (1) employing the aligned CNTs (~70□m in height) as interdigitated finger electrodes to increase sensing area and initial capacitance; (2) 3D interdigitated finger electrodes and anchor structures are naturally formed by the use of anisotropically-etched silicon mold; (3) the 3D CNTs electrodes and electrical routings are batch-fabricated on the silicon substrate, and are transferred to the flexible polymer substrate by polymer molding; (4) the CNTs-polymer composites as sensing electrodes and electrical routing are more robust and can avoid the problem of delamination; (5) the integration of 3D polymer structure can be further adopted as flexible sensors with multi-functional sensing. Preliminary fabrication results demonstrate a flexible capacitive sensor with 50□□m high CNTs interdigitated electrodes on poly-dimethylsiloxane (PDMS) substrate. The tests show that its typical capacitance change is several dozens of fF and the gauge factor ranges 4.6~6.5 for strain and bending curvature measurement; the sensitivity of tactile force is 1.11%/N; the proximity distance can be detected up to 1500□m away from the sensor.

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