Closed-Loop Characterization of Noise and Stability in a Mode-Localized Resonant MEMS Sensor

TY - JOUR

T1 - Closed-Loop Characterization of Noise and Stability in a Mode-Localized Resonant MEMS Sensor

AU - Pandit, Milind

AU - Zhao, Chun

AU - Sobreviela, Guillermo

AU - Mustafazade, Arif

AU - Du, Sijun

AU - Zou, Xudong

AU - Seshia, Ashwin A.

N1 - Funding Information: Manuscript received September 29, 2017; accepted October 22, 2018. Date of publication October 26, 2018; date of current version January 14, 2019. This work was supported in part by Innovate, U.K. and in part by Natural Environment Research Council. This paper is an extended version of a conference paper presented at the 2017 European Frequency and Time Forum and International Frequency Control Symposium [1]. (Milind Pandit and Chun Zhao contributed equally to this work.) (Corresponding author: Milind Pandit.) M. Pandit, C. Zhao, G. Sobreviela, A. Mustafazade, S. Du, and A. A. Seshia are with the Nanoscience Centre, University of Cambridge, Cambridge CB3 0FF, U.K. (e-mail: mnp26. . .ac.uk; cz319. . .ac.uk; aas41. . .ac.uk). Publisher Copyright: © 1986-2012 IEEE.

PY - 2019/1

Y1 - 2019/1

N2 - This paper presents results from the closed-loop characterization of an electrically coupled mode-localized sensor topology including measurements of amplitude ratios over a long duration, stability, noise floor, and the bandwidth of operation. The sensitivity of the prototype sensor is estimated to be-5250 in the linear operation regime. An input-referred stability of 84 ppb with respect to normalized stiffness perturbations is achieved at 500 s. When compared to frequency shift sensing within the same device, amplitude ratio sensing provides higher resolution for long-term measurements due to the intrinsic common-mode rejection properties of a mode-localized system. A theoretical framework is established to quantify noise floor associated with measurements validated through numerical simulations and experimental data. In addition, the operating bandwidth of the sensor is found to be 3.5 Hz for 3-dB flatness.

AB - This paper presents results from the closed-loop characterization of an electrically coupled mode-localized sensor topology including measurements of amplitude ratios over a long duration, stability, noise floor, and the bandwidth of operation. The sensitivity of the prototype sensor is estimated to be-5250 in the linear operation regime. An input-referred stability of 84 ppb with respect to normalized stiffness perturbations is achieved at 500 s. When compared to frequency shift sensing within the same device, amplitude ratio sensing provides higher resolution for long-term measurements due to the intrinsic common-mode rejection properties of a mode-localized system. A theoretical framework is established to quantify noise floor associated with measurements validated through numerical simulations and experimental data. In addition, the operating bandwidth of the sensor is found to be 3.5 Hz for 3-dB flatness.

KW - Force sensitivity

KW - force sensor

KW - MEMS

KW - resonant sensor

KW - thermal noise

UR - http://www.scopus.com/inward/record.url?scp=85055717407&partnerID=8YFLogxK

U2 - 10.1109/TUFFC.2018.2878241

DO - 10.1109/TUFFC.2018.2878241

M3 - Article

C2 - 30371360

AN - SCOPUS:85055717407

SN - 0885-3010

VL - 66

SP - 170

EP - 180

JO - IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control

JF - IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control

IS - 1

M1 - 8510830

ER -