title: Piezoelectric potential gated field-effect transistor based on a free-standing ZnO wire.
abstract: We report an external force triggered field-effect transistor based on a free-standing piezoelectric fine wire (PFW). The device consists of an Ag source electrode and an Au drain electrode at two ends of a ZnO PFW, which were separated by an insulating polydimethylsiloxane (PDMS) thin layer. The working principle of the sensor is proposed based on the piezoelectric potential gating effect. Once subjected to a mechanical impact, the bent ZnO PFW cantilever creates a piezoelectric potential distribution across it width at its root and simultaneously produces a local reverse depletion layer with much higher donor concentration than normal, which can dramatically change the current flowing from the source electrode to drain electrode when the device is under a fixed voltage bias. Due to the free-standing structure of the sensor device, it has a prompt response time less than 20 ms and quite high and stable sensitivity of 2%/microN. The effect from contact resistance has been ruled out.
authors.affiliation: School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, USA.
authors.forename: Peng
authors.initials: P
authors.lastname: Fei
authors.forename: Ping-Hung
authors.initials: PH
authors.lastname: Yeh
authors.forename: Jun
authors.initials: J
authors.lastname: Zhou
authors.forename: Sheng
authors.initials: S
authors.lastname: Xu
authors.forename: Yifan
authors.initials: Y
authors.lastname: Gao
authors.forename: Jinhui
authors.initials: J
authors.lastname: Song
authors.forename: Yudong
authors.initials: Y
authors.lastname: Gu
authors.forename: Yanyi
authors.initials: Y
authors.lastname: Huang
authors.forename: Zhong Lin
authors.initials: ZL
authors.lastname: Wang