Department of Chemical Engineering, Stanford University, Stanford, California 94305, USA.
Department of Materials Science and Engineering, Stanford University, Stanford, California 94305, USA.
Nature. 2018 Mar 1;555(7694):83-88. doi: 10.1038/nature25494. Epub 2018 Feb 19.
Skin-like electronics that can adhere seamlessly to human skin or within the body are highly desirable for applications such as health monitoring, medical treatment, medical implants and biological studies, and for technologies that include human-machine interfaces, soft robotics and augmented reality. Rendering such electronics soft and stretchable-like human skin-would make them more comfortable to wear, and, through increased contact area, would greatly enhance the fidelity of signals acquired from the skin. Structural engineering of rigid inorganic and organic devices has enabled circuit-level stretchability, but this requires sophisticated fabrication techniques and usually suffers from reduced densities of devices within an array. We reasoned that the desired parameters, such as higher mechanical deformability and robustness, improved skin compatibility and higher device density, could be provided by using intrinsically stretchable polymer materials instead. However, the production of intrinsically stretchable materials and devices is still largely in its infancy: such materials have been reported, but functional, intrinsically stretchable electronics have yet to be demonstrated owing to the lack of a scalable fabrication technology. Here we describe a fabrication process that enables high yield and uniformity from a variety of intrinsically stretchable electronic polymers. We demonstrate an intrinsically stretchable polymer transistor array with an unprecedented device density of 347 transistors per square centimetre. The transistors have an average charge-carrier mobility comparable to that of amorphous silicon, varying only slightly (within one order of magnitude) when subjected to 100 per cent strain for 1,000 cycles, without current-voltage hysteresis. Our transistor arrays thus constitute intrinsically stretchable skin electronics, and include an active matrix for sensory arrays, as well as analogue and digital circuit elements. Our process offers a general platform for incorporating other intrinsically stretchable polymer materials, enabling the fabrication of next-generation stretchable skin electronic devices.
皮肤般的电子产品，可以无缝地贴合人体皮肤或内部，非常适合健康监测、医疗治疗、医疗植入物和生物研究等应用，也适用于人机界面、软机器人和增强现实等技术。使这些电子产品变得柔软和具有弹性，就像人类的皮肤一样，会让它们更加舒适，并且通过增加接触面积，极大地提高从皮肤获取信号的保真度。刚性无机和有机器件的结构工程已经实现了电路级的可拉伸性，但这需要复杂的制造技术，并且通常会导致器件阵列中的器件密度降低。我们认为，所需的参数，如更高的机械可变形性和鲁棒性、更好的皮肤兼容性和更高的器件密度，可以通过使用具有内在可拉伸性的聚合物材料来提供。然而，具有内在可拉伸性的材料和器件的生产仍处于起步阶段：已经有报道称具有内在可拉伸性的材料，但由于缺乏可扩展的制造技术，功能齐全的、具有内在可拉伸性的电子产品尚未得到展示。在这里，我们描述了一种制造工艺，该工艺可从各种具有内在可拉伸性的电子聚合物中实现高产量和均匀性。我们展示了一个具有前所未有的器件密度（每平方厘米 347 个晶体管）的具有内在可拉伸性的聚合物晶体管阵列。这些晶体管的平均载流子迁移率与非晶硅相当，在经受 100%应变 1000 个循环时仅略有变化（在一个数量级内），并且没有电流-电压滞后。因此，我们的晶体管阵列构成了具有内在可拉伸性的皮肤电子产品，包括用于感应阵列的有源矩阵，以及模拟和数字电路元件。我们的工艺为整合其他具有内在可拉伸性的聚合物材料提供了一个通用平台，使下一代可拉伸皮肤电子设备的制造成为可能。
