title: Love-mode surface acoustic wave devices based on multilayers of TeO2/ZnO(112¯0)/Si(100) with high sensitivity and temperature stability.
abstract: A multilayer structure of TeO2/interdigital transducers (IDTs)/ZnO(112¯0)/Si(100) was proposed and investigated to achieve both high sensitivity and temperature-stability for bio-sensing applications. Dispersions of phase velocities, electromechanical coupling coefficients K2, temperature coefficient of delay (TCD) and sensitivity in the multilayer structures were simulated as functions of normalized thicknesses of ZnO (hZnO/λ) and TeO2(hTeO2/λ) films. The fundamental mode of Love mode (LM) - surface acoustic wave (SAW) shows a larger value of K2and higher sensitivity compared with those of the first mode. TeO2film with a positive TCD not only compensates the temperature effect induced due to the negative TCD of ZnO(112¯0)/Si(100), but also enhances the sensitivity of the love mode device. The optimal normalized thickness ratios were identified to be hTeO2/λ=0.021 and hZnO/λ=0.304, and the devices with such structures can which generate a normalized sensitivity of -1.04×10-3m3/kg, a TCD of 0.009ppm/°C, and a K2value of 2.76%.
authors.affiliation: College of Physics and Energy, Shenzhen Key Laboratory of Sensor Technology, Shenzhen University, 518060, China; Faculty of Engineering and Environment, Northumbria University, Newcastle upon Tyne NE1 8ST, UK.
authors.forename: Jing-Ting
authors.initials: JT
authors.lastname: Luo
authors.affiliation: College of Physics and Energy, Shenzhen Key Laboratory of Sensor Technology, Shenzhen University, 518060, China.
authors.forename: Ao-Jie
authors.initials: AJ
authors.lastname: Quan
authors.affiliation: College of Physics and Energy, Shenzhen Key Laboratory of Sensor Technology, Shenzhen University, 518060, China.
authors.forename: Guang-Xing
authors.initials: GX
authors.lastname: Liang
authors.affiliation: College of Physics and Energy, Shenzhen Key Laboratory of Sensor Technology, Shenzhen University, 518060, China.
authors.forename: Zhuang-Hao
authors.initials: ZH
authors.lastname: Zheng
authors.affiliation: Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne NE2 4HH, UK.
authors.forename: Sami
authors.initials: S
authors.lastname: Ramadan
authors.affiliation: Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne NE2 4HH, UK. Electronic address: chen.fu@newcastle.ac.uk.
authors.forename: Chen
authors.initials: C
authors.lastname: Fu
authors.affiliation: Institute of Acoustics, Chinese Academy of Sciences, 100190 Beijing, China. Electronic address: lhl@mail.ioa.ac.cn.
authors.forename: Hong-Lang
authors.initials: HL
authors.lastname: Li
authors.affiliation: Faculty of Engineering and Environment, Northumbria University, Newcastle upon Tyne NE1 8ST, UK.
authors.forename: Yong-Qing
authors.initials: YQ
authors.lastname: Fu
keywords: Love wave; Multilayered structure; Surface acoustic wave; ZnO film