Mode Analysis of Pt/LGS Surface Acoustic Wave Devices.
Sensors (Basel). 2020 Dec 11; 20(24)S

Abstract

Platinum (Pt) gratings on langasite (LGS) substrates are a widely used structures in high temperature surface acoustic wave (SAW) devices. Multiple modes can be excited in Pt/LGS SAW devices owing to the heavy weight of the Pt electrode and leaky waves in the LGS substrate. In this work, we report on a detailed mode analysis of Pt/LGS SAW devices, where three commonly used LGS cuts are considered. A three-dimensional (3D) finite element method (FEM) numerical model was developed, and the simulation and experiment results were compared. The experiment and simulation results showed that there are two modes excited in the Pt/LGS SAW devices with Euler angle (0°, 138.5°, 27°) and (0°, 138.5°, 117°), which are Rayleigh-type SAW and SH-type leaky wave, respectively. Only the Rayleigh-type mode was observed in the Pt/LGS SAW devices with Euler angle (0°, 138.5°, 72°). It was found that the acoustic velocities are dependent on the wavelength, which is attributed to the change of wave penetration depth in interdigital transducers (IDTs) and the velocity dispersion can be modulated by the thickness of the Pt electrode. We also demonstrated that addition of an Al2O3 passivation layer has no effect on the wave modes, but can increase the resonant frequencies. This paper provides a better understanding of the acoustic modes of Pt/LGS SAW devices, as well as useful guidance for device design. It is believed that the Rayleigh-type SAW and SH-type leaky waves are potentially useful for dual-mode sensing applications in harsh environments, to achieve multi-parameter monitoring or temperature-compensation on a single chip.

Links

PMC Free PDF

Authors+Show Affiliations

Xu H

Key Laboratory of Advanced Micro/Nano Electronic Devices & Smart Systems of Zhejiang, College of Information Science and Electronic Engineering, Zhejiang University, Hangzhou 310027, China. Hangzhou Global Scientific and Technological Innovation Center, Zhejiang University, Hangzhou 310018, China.

Ministry of Education Key Laboratory of RF Circuits and Systems, Hangzhou Dianzi University, Hangzhou 310018, China.

Xuan W

Hangzhou Global Scientific and Technological Innovation Center, Zhejiang University, Hangzhou 310018, China. Ministry of Education Key Laboratory of RF Circuits and Systems, Hangzhou Dianzi University, Hangzhou 310018, China.

Huang S

Shi L

Luo J

Pub Type(s)

Journal Article

Language

eng

PubMed ID

33322434

Citation

Xu, Hongsheng, et al. "Mode Analysis of Pt/LGS Surface Acoustic Wave Devices." Sensors (Basel, Switzerland), vol. 20, no. 24, 2020.

Xu H, Jin H, Dong S, et al. Mode Analysis of Pt/LGS Surface Acoustic Wave Devices. Sensors (Basel). 2020;20(24).

Xu, H., Jin, H., Dong, S., Song, X., Chen, J., Xuan, W., Huang, S., Shi, L., & Luo, J. (2020). Mode Analysis of Pt/LGS Surface Acoustic Wave Devices. Sensors (Basel, Switzerland), 20(24). https://doi.org/10.3390/s20247111

Xu H, et al. Mode Analysis of Pt/LGS Surface Acoustic Wave Devices. Sensors (Basel). 2020 Dec 11;20(24) PubMed PMID: 33322434.

* Article titles in AMA citation format should be in sentence-case

TY - JOUR T1 - Mode Analysis of Pt/LGS Surface Acoustic Wave Devices. AU - Xu,Hongsheng, AU - Jin,Hao, AU - Dong,Shurong, AU - Song,Xinyu, AU - Chen,Jinkai, AU - Xuan,Weipeng, AU - Huang,Shuyi, AU - Shi,Lin, AU - Luo,Jikui, Y1 - 2020/12/11/ PY - 2020/11/21/received PY - 2020/12/05/revised PY - 2020/12/09/accepted PY - 2020/12/16/entrez PY - 2020/12/17/pubmed PY - 2020/12/17/medline KW - langasite KW - mode analysis KW - platinum KW - surface acoustic wave KW - velocity dispersion JF - Sensors (Basel, Switzerland) JO - Sensors (Basel) VL - 20 IS - 24 N2 - Platinum (Pt) gratings on langasite (LGS) substrates are a widely used structures in high temperature surface acoustic wave (SAW) devices. Multiple modes can be excited in Pt/LGS SAW devices owing to the heavy weight of the Pt electrode and leaky waves in the LGS substrate. In this work, we report on a detailed mode analysis of Pt/LGS SAW devices, where three commonly used LGS cuts are considered. A three-dimensional (3D) finite element method (FEM) numerical model was developed, and the simulation and experiment results were compared. The experiment and simulation results showed that there are two modes excited in the Pt/LGS SAW devices with Euler angle (0°, 138.5°, 27°) and (0°, 138.5°, 117°), which are Rayleigh-type SAW and SH-type leaky wave, respectively. Only the Rayleigh-type mode was observed in the Pt/LGS SAW devices with Euler angle (0°, 138.5°, 72°). It was found that the acoustic velocities are dependent on the wavelength, which is attributed to the change of wave penetration depth in interdigital transducers (IDTs) and the velocity dispersion can be modulated by the thickness of the Pt electrode. We also demonstrated that addition of an Al2O3 passivation layer has no effect on the wave modes, but can increase the resonant frequencies. This paper provides a better understanding of the acoustic modes of Pt/LGS SAW devices, as well as useful guidance for device design. It is believed that the Rayleigh-type SAW and SH-type leaky waves are potentially useful for dual-mode sensing applications in harsh environments, to achieve multi-parameter monitoring or temperature-compensation on a single chip. SN - 1424-8220 UR - https://www.unboundmedicine.com/medline/citation/33322434/Mode_Analysis_of_Pt/LGS_Surface_Acoustic_Wave_Devices_ DB - PRIME DP - Unbound Medicine ER -

Tags

Mode Analysis of Pt/LGS Surface Acoustic Wave Devices.Sensors (Basel). 2020 Dec 11; 20(24)S