Piezotronics based on piezoelectric fine wires have show diverse of potential applications [1-3]. A piezotronic device is normally characterized by its capable of output pulsed piezoelectrical signals upon a load of strain. Strain sensor or tactile sensor could be a promising application for piezotronic devices [1, 2]. This field is pioneered by Zhong Lin Wang’s group. Zhong Lin Wang’s group has just demonstrated a tactile imaging device based on an array of piezotronic transistors [1]. This work opened a broad range of potential applications such as human-electronic interfacing, smart skin and micro- and nanoelectromechanical systems. The unique thing of this type of tactile sensor is that its function mechanism is similar with that of tactile sensing of human beings, which is essentially a bio-piezo effect. In this report, we demonstrate a horizontally aligned piezotronic component based on a ZnO piezoelectric fine wire bridging between two copper electrodes. We integrate a fiber across the ZnO piezoelectric fine wire and so it forms a ridge across the piezotronic component after PDMS packaging. The ridge over the piezotronic component serves as a strain introducing component mimic human being finger prints. The devices are used to touch (press and slide on) a series of objects with period textures on the surface. The output piezoelectric pulses are recorded and correlated to the period textures of the objects been touched.

This work was financially supported by the National Natural Science Foundation of China (Grant Nos. 61172041, 91123018, 61172040), and the Fundamental Research Funds for the Central Universities. The authors also thank Prof. Yong Qin for his valuable comments on the device fabrications.

References:

[1] Wenzhuo Wu, Xiaonan Wen, Zhong Lin Wang, Taxel-Addressable matrix of vertical-nanowire piezotronic transistors for active and adaptive tactile imaging, Science 340, 952 (2013).

[2] Rusen Yang, Yong Qin, Liming Dai and Zhong Lin Wang, Power generation with laterally packaged piezoelectric fine wires, Nature Nanotechnology, 4, 34-39 (2009).

[3] Jun Zhou, Yudong Gu, Peng Fei, Wenjie Mai, et al., Flexible Piezotronic Strain Sensor, Nano Lett. 8, 3035-3040 (2008).

Liu Weihua

Xi'an Jiaotong University

Appearances