title: Lateral-field-excited bulk acoustic wave sensors on langasite working on different operational modes.
abstract: Lateral-field-excited (LFE) bulk acoustic wave sensors on langasite working on different operational modes are investigated and compared. Langasite LFE sensors on pure-LFE mode and pseudo-LFE mode are designed and fabricated. The sensitivities of the devices to changes in liquid electrical properties (e.g., conductivity or permittivity) and micro-mass changes on their surfaces were tested and compared. The experimental results show that compared with langasite pure-LFE devices, langasite pseudo-LFE devices have superior sensitivities to both liquid conductivity and liquid permittivity changes. For the micro-mass changes, the pure- LFE devices showed high sensitivity, whereas the pseudo-LFE devices do not, because they cannot resonate in air. On this basis, the physical interpretation of these results is discussed.
authors.forename: Tingfeng
authors.initials: T
authors.lastname: Ma
authors.forename: Ji
authors.initials: J
authors.lastname: Wang
authors.forename: Jianke
authors.initials: J
authors.lastname: Du
authors.forename: Lili
authors.initials: L
authors.lastname: Yuan
authors.forename: Zhenghua
authors.initials: Z
authors.lastname: Qian
authors.forename: Zhitian
authors.initials: Z
authors.lastname: Zhang
authors.forename: Chao
authors.initials: C
authors.lastname: Zhang