A Flexible Film Bulk Acoustic Resonator Based on β-Phase Polyvinylidene Fluoride Polymer
Ting Wu,
Hao Jin,
Shurong Dong,
Weipeng Xuan,
Hongsheng Xu,
Leihe Lu,
Zijing Fang,
Shuyi Huang,
Xiang Tao,
Lin Shi,
Shuting Liu,
Jikui Luo
Affiliations
Ting Wu
Key Lab. of Advanced Micro/Nano Electronic Devices and Smart Systems of Zhejiang, College of Information Science and Electronic Engineering, Zhejiang University, Hangzhou 310027, China
Hao Jin
Key Lab. of Advanced Micro/Nano Electronic Devices and Smart Systems of Zhejiang, College of Information Science and Electronic Engineering, Zhejiang University, Hangzhou 310027, China
Shurong Dong
Key Lab. of Advanced Micro/Nano Electronic Devices and Smart Systems of Zhejiang, College of Information Science and Electronic Engineering, Zhejiang University, Hangzhou 310027, China
Weipeng Xuan
Ministry of Education Key Laboratory of RF Circuits and Systems, Hangzhou Dianzi University, Hangzhou 310018, China
Hongsheng Xu
Key Lab. of Advanced Micro/Nano Electronic Devices and Smart Systems of Zhejiang, College of Information Science and Electronic Engineering, Zhejiang University, Hangzhou 310027, China
Leihe Lu
Key Lab. of Advanced Micro/Nano Electronic Devices and Smart Systems of Zhejiang, College of Information Science and Electronic Engineering, Zhejiang University, Hangzhou 310027, China
Zijing Fang
Key Lab. of Advanced Micro/Nano Electronic Devices and Smart Systems of Zhejiang, College of Information Science and Electronic Engineering, Zhejiang University, Hangzhou 310027, China
Shuyi Huang
Key Lab. of Advanced Micro/Nano Electronic Devices and Smart Systems of Zhejiang, College of Information Science and Electronic Engineering, Zhejiang University, Hangzhou 310027, China
Xiang Tao
Key Lab. of Advanced Micro/Nano Electronic Devices and Smart Systems of Zhejiang, College of Information Science and Electronic Engineering, Zhejiang University, Hangzhou 310027, China
Lin Shi
Key Lab. of Advanced Micro/Nano Electronic Devices and Smart Systems of Zhejiang, College of Information Science and Electronic Engineering, Zhejiang University, Hangzhou 310027, China
Shuting Liu
Key Lab. of Advanced Micro/Nano Electronic Devices and Smart Systems of Zhejiang, College of Information Science and Electronic Engineering, Zhejiang University, Hangzhou 310027, China
Jikui Luo
Key Lab. of Advanced Micro/Nano Electronic Devices and Smart Systems of Zhejiang, College of Information Science and Electronic Engineering, Zhejiang University, Hangzhou 310027, China
This paper reports a novel flexible film bulk acoustic resonator (FBAR) based on β -phase polyvinylidene fluoride (PVDF) piezoelectric polymer. The proposed device was simulated and evaluated; then, a low-temperature photolithography process with a double exposure method was developed to pattern the electrodes for the device, which enabled the device to retain the piezoelectric properties of the β -phase PVDF film. Results showed that the β-phase PVDF FBARs had a resonant frequency round 9.212 MHz with a high electromechanical coupling coefficient ( k 2 ) of 12.76% ± 0.56%. The device performed well over a wide bending-strain range up to 2400 μ ε owing to its excellent flexibility. It showed good stability as a strain sensor with a sensitivity of 80 Hz / μ ε , and no visible deterioration was observed after cyclic bending tests. The PVDF FBAR also exhibited an exceptionally large temperature coefficient of frequency (TCF) of −4630 ppm / K , two orders of magnitude larger than those of other FBARs based on common inorganic piezoelectric materials, extraordinarily high sensitivity for temperature sensing. All results showed that β -phase PVDF FBARs have the potential to expand the application scope for future flexible electronics.