32 x 32 CMOS 微機電電容式觸覺感測器之開發

Development of 32 x 32 CMOS MEMS Capacitive Tactile Sensors

黃子祐(Tzu-Yu Huang)

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(2022年)

摘要

隨著機器人產業的快速發展，使得觸覺感測的研究也越來越熱門，透過CMOS標準製程來設計電容式觸覺感測晶片，能同時有體積小和成本低的優勢，此外，本論文在設計上不同於一般靜態量測，電路使用高頻操作以利動態訊號量測。
本研究提出一種CMOS電容式觸覺感測晶片，利用硫酸濕蝕刻、反應離子蝕刻等後製程步驟來產生32×32感測陣列，每個感測元件由金屬層和介電層組合而成，結構分為上下電極，上電極用來接觸外力做感測，下電極為固定電極連接電路，晶片的面積大小為6760μm×4600μm，觸覺感測陣列面積為4800μm×2400μm，在實驗時，透過自製印章以及探針可以分別做靜態和動態的量測。
本感測晶片透過將電極形狀設計為八角形來提高晶片的有效感測面積，模擬上最大量測壓力為1.5kPa；在量測上，結構感測度為8.161 fF/kPa，在4 MHz訊號積分時間下，輸出訊號感測度為 27.2mV/kPa。在動態量測方面，可以得到針和印章碰撞到晶片表面的連續變化結果。

關鍵字

電容感測 ； 觸覺感測 ； 靜態感測 ； 動態感測

並列摘要

With the rapid development of the robotics industry, the research on tactile sensing has become more and more popular. The design of capacitive tactile sensing chips through the CMOS standard process can simultaneously have the advantages of small size and low cost. In addition, this paper is different from general static measurement, the circuit uses high frequency operation to facilitate dynamic signal measurement.
This research proposes a CMOS capacitive touch sensor chip, which uses sulfuric acid wet etching, reactive ion etching and other post-process steps to produce a 32×32 sensing array. Each sensing element is composed of CMOS metal layer and inter-metal dielectric layers. The structure is divided into upper and lower electrodes. The upper electrode is used for sensing external force, and the lower electrode is a fixed electrode connecting to the sensing circuit. The area of the chip is 6760μm×4600μm, and the area of the tactile sensing array is 4800μm×2400μm. In the experiment, the self-made seal and the probe can be used for static and dynamic measurements.
This sensor chip promotes the effective sensing area of the chip by designing the electrode shape as an octagonal shape. The maximum measurement pressure is 9000Pa , and the measurement result is 8.161fF/kPa. Under the 4MHz signal integration time, the output signal sensitivity is 27.2mV/kPa. In terms of dynamic measurement, it can be obtained that the probe and the self-made seal hit the chip surface as a result of continuous changes.

並列關鍵字

Capacitive ； Tactile sensing ； Static measurement ； Dynamic measurement

參考文獻

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