Year: 2025
Type: article
Abstract: Bulk acoustic wave (BAW) resonators, with their exceptional high-frequency performance and excellent quality factor, have become a key driver of advances in sensing technology. This study reports the fabrication and characterization of a force sensor based on a solid mounted resonator (SMR) structure. This SMR device utilizes a high resonance frequency of 2.257 GHz as its core sensing element. The operational mechanism involves the application of an external load inducing localized downward mechanical deformation in the SMR film at the pin contact region, thereby generating significant in-plane compressive stress within the piezoelectric layer. The applied strain modifies the intrinsic elastic and piezoelectric constants of the film, thereby changing both the acoustic phase velocity and the electromechanical coupling coefficient (Kt2), which ultimately leads to a measurable shift in the resonance frequency. The experimental results reveal a deterministic and robust correlation between the resonance frequency shift and the applied load, which forms a precise function relationship enabling the device to achieve a high sensitivity of 37.79 MHz/N. This indicates that it may possess good application and development potential in various complex industrial fields.
Source: Sensors
DOI: 10.3390/s25237288
Authors: Wanqing Zuo, Xiyu Gu, Tingting Yang, Qinwen Xu, Haiyang Li, Yao Cai, Chengliang Sun
Institutions: Hong Kong Polytechnic University, Wuhan University
Language: English
Subfield: Biomedical Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $3,137
Awards: G486004951, G6514514836
OpenAlex ID: W4417050462