Department of Chemical Engineering , Hanyang University , Seoul 04763 , Republic of Korea.
Department of Mechanical Engineering, School of Engineering , Kyung Hee University , Yongin 17104 , Republic of Korea.
ACS Appl Mater Interfaces. 2018 Sep 19;10(37):31472-31479. doi: 10.1021/acsami.8b09840. Epub 2018 Sep 5.
The development of a highly sensitive artificial mechanotransducer that mimics the tactile sensing features of human skin has been a big challenge in electronic skin research. Here, we demonstrate an ultrasensitive, low-power oxide transistor-based mechanotransducer modulated by microstructured, deformable ionic dielectrics, which is consistently sensitive to a wide range of pressures from 1 to 50 kPa. To this end, we designed a viscoporoelastic and ionic thermoplastic polyurethane (i-TPU) with micropyramidal feature as a pressure-sensitive gate dielectric for the indium-gallium-zinc-oxide (IGZO) transistor-based mechanotransducer, which leads to an unprecedented sensitivity of 43.6 kPa, which is 23 times higher than that of a capacitive mechanotransducer. This is because the pressure-induced ion accumulation at the interface of the i-TPU dielectric and IGZO semiconductor effectively modulates the conducting channel, which contributed to the enhanced current level under pressure. We believe that the ionic transistor-type mechanotransducer suggested by us will be an effective way to perceive external tactile stimuli over a wide pressure range even under low power (<4 V), which might be one of the candidates to directly emulate the tactile sensing capability of human skin.
开发一种能够模拟人类皮肤触觉传感特性的高灵敏度人工机械换能器一直是电子皮肤研究中的一大挑战。在这里，我们展示了一种基于氧化物晶体管的超灵敏、低功耗机械换能器，该换能器由微结构、可变形离子电介质调制，能够持续感应从 1 kPa 到 50 kPa 的广泛压力范围。为此，我们设计了一种具有微金字塔特征的粘弹性和离子热塑性聚氨酯（i-TPU）作为压力敏感栅介质，用于基于铟镓锌氧化物（IGZO）晶体管的机械换能器，这导致了前所未有的 43.6 kPa 的灵敏度，比电容式机械换能器高 23 倍。这是因为压力诱导的离子在 i-TPU 介电层和 IGZO 半导体界面的积累有效地调制了导电通道，这有助于在压力下提高电流水平。我们相信，我们提出的离子晶体管型机械换能器将是一种在低功率（<4 V）下有效感知宽压力范围外部触觉刺激的有效方式，它可能是直接模拟人类皮肤触觉感知能力的候选方案之一。
