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Tian et al. Soft Sci 2023;3:30 Soft Science
DOI: 10.20517/ss.2023.21

Review Article Open Access

Flexible pressure and temperature sensors towards

e-skin: material, mechanism, structure and
fabrication

Shengrui Tian, Yilin Wang, Haitao Deng, Yan Wang, Xiaosheng Zhang *

School of Integrated Circuit Science and Engineering, University of Electronic Science and Technology of China, Chengdu 611731,
Sichuan, China.
* Correspondence to: Prof. Xiaosheng Zhang, School of Integrated Circuit Science and Engineering, University of
Electronic Science and Technology of China, Chengdu 611731, Sichuan, China. E-mail: zhangxs@uestc.edu.cn
How to cite this article: Tian S, Wang Y, Deng H, Wang Y, Zhang X. Flexible pressure and temperature sensors towards e-skin:
material, mechanism, structure and fabrication. Soft Sci 2023;3:30. https://dx.doi.org/10.20517/ss.2023.21

Received: 10 May 2023 First Decision: 16 Jun 2023 Revised: 1 Jul 2023 Accepted: 10 Jul 2023 Published: 7 Aug 2023
Academic Editor: Zhifeng Ren Copy Editor: Lin He Production Editor: Lin He

Abstract
Electronic skin (E-skin) has gained significant attention due to its potential applications in the Internet of Things
(IoT), artificial intelligence (AI), and flexible multi-sensing systems. Mimicking human skin, e-skin sensing devices
can be employed in various scenarios. Among the most important sensing elements for tactile e-skin sensors are
pressure and temperature sensors, which have increasingly garnered research interest over the past few decades.
However, the design and fabrication of advanced pressure and temperature sensors can be challenging owing to
complications such as signal interference, complex mechanism integration, and structural design issues. This
review provides an overview of flexible pressure and temperature sensors used in e-skin, covering four main
perspectives: material selection, mechanism integration, structural design, and manufacturing methods. The
materials of different elements in the entire sensing system are comprehensively discussed, along with single and
compound mechanisms of pressure and temperature sensing. Pressure and temperature sensors are divided into
two types based on their electric output signals, which are exemplified in detail. The manufacturing methods used
to fabricate these sensors, including printing methods, are outlined. Lastly, a summary of the future challenges
faced by flexible pressure and temperature sensors used in e-skin is presented.

Keywords: Flexible electronics, electronic skin, printed sensors, MEMS, human-machine interaction

© The Author(s) 2023. Open Access This article is licensed under a Creative Commons Attribution 4.0
International License (https://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, sharing,
adaptation, distribution and reproduction in any medium or format, for any purpose, even commercially, as
long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and
indicate if changes were made.

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