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Title: An Analytical Model for Dual Gate Piezoelectrically Sensitive ZnO Thin Film Transistors
Abstract Highly sensitive force sensors of piezoelectric zinc oxide (ZnO) dual‐gate thin film transistors (TFTs) are reported together with an analytical model that elucidates the physical origins of their response. The dual‐gate TFTs are fabricated on a polyimide substrate and exhibited a field effect mobility of ≈5 cm2V−1s−1,Imax/Iminratio of 107, and a subthreshold slope of 700 mV dec−1, and demonstrated static and transient current changes under external forces with varying amplitude and polarity in different gate bias regimes. To understand the current modulation of the dual‐gate TFT with independently biased top and bottom gates, an analytical model is developed. The model includes accumulation channels at both surfaces and a bulk channel within the film and accounts for the force‐induced piezoelectric charge density. The microscopic piezoelectric response that modulates the energy‐band edges and correspondent current–voltage characteristics are accurately portrayed by this model. Finally, the field‐tunable force response in single TFT is demonstrated as a function of independent bias for the top and bottom gates with a force response range from −0.29 to 22.7 nA mN−1. This work utilizes intuitive analytical models to shed light on the correlation between the material properties with the force response in piezoelectric TFTs.  more » « less
Award ID(s):
1728497
PAR ID:
10449872
Author(s) / Creator(s):
 ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Advanced Materials Technologies
Volume:
6
Issue:
8
ISSN:
2365-709X
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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