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. 2022 Jul 18;65(9):1995–2006. doi: 10.1007/s11431-022-2074-8

Flexible hybrid electronics: Enabling integration techniques and applications

Hao Wu 1, YongAn Huang 1, ZhouPing Yin 1,✉
PMCID: PMC9302228  PMID: 35892001

Abstract

The conventional electronic systems enabled by rigid electronic are prone to malfunction under deformation, greatly limiting their application prospects. As an emerging platform for applications in healthcare monitoring and human-machine interface (HMI), flexible electronics have attracted growing attention due to its remarkable advantages, such as stretchability, flexibility, conformability, and wearing comfort. However, to realize the overall electronic systems, rigid components are also required for functions such as signal acquisition and transmission. Therefore, flexible hybrid electronics (FHE), which simultaneously possesses the desirable flexibility and enables the integration of rigid components for functionality, has been emerging as a promising strategy. This paper reviews the enabling integration techniques for FHE, including technologies for two-dimensional/three-dimensional (2D/3D) interconnects, bonding of rigid integrated circuit (IC) chips to soft substrate, stress-isolation structures, and representative applications of FHE. In addition, future challenges and opportunities involved in FHE-based systems are also discussed.

Footnotes

This work was supported by the Flexible Electronics Research Center of Huazhong University of Science and Technology (HUST) for providing experiment facility, the National Natural Science Foundation of China (Grant Nos. 51820105008, U2013213, and 92048302), and the Technology Innovation Project of Hubei Province of China (Grant No. 2019AEA171). We also thank YANG GanGuang, FANG Han, HUANG Xin, GUO Wei, QIU YuQi, and ZHENG QingYang for the assistance during the preparation of this paper.

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