title: Investigation of the frequency shift of a SAD circuit loop and the internal micro-cantilever in a gas sensor.
abstract: Micro-cantilever sensors for mass detection using resonance frequency have attracted considerable attention over the last decade in the field of gas sensing. For such a sensing system, an oscillator circuit loop is conventionally used to actuate the micro-cantilever, and trace the frequency shifts. In this paper, gas experiments are introduced to investigate the mechanical resonance frequency shifts of the micro-cantilever within the circuit loop(mechanical resonance frequency, MRF) and resonating frequency shifts of the electric signal in the oscillator circuit (system working frequency, SWF). A silicon beam with a piezoelectric zinc oxide layer is employed in the experiment, and a Self-Actuating-Detecting (SAD) circuit loop is built to drive the micro-cantilever and to follow the frequency shifts. The differences between the two resonating frequencies and their shifts are discussed and analyzed, and a coefficient α related to the two frequency shifts is confirmed.
authors.affiliation: Department of Precision Instruments and Mechanics, Tsinghua University, Beijing 100084, China. guanl04@mails.tsinghua.edu.cn
authors.forename: Liu
authors.initials: L
authors.lastname: Guan
authors.forename: Jiahao
authors.initials: J
authors.lastname: Zhao
authors.forename: Shijie
authors.initials: S
authors.lastname: Yu
authors.forename: Peng
authors.initials: P
authors.lastname: Li
authors.forename: Zheng
authors.initials: Z
authors.lastname: You
mesh_terms: D004581:Electronics; D005740:Gases / Q000032:analysis*
chemical_list: D005740:Gases