Silicon-based micromembranes with piezoelectric actuation and piezoresistive detection for sensing purposes in liquid media

• Published in: Journal of micromechanics and microengineering 2010-07, Vol.20 (7), p.075014-075014
• Main Authors: Alava, T, Mathieu, F, Mazenq, L, Soyer, C, Remiens, D, Nicu, L
• Format: Article
• Language: English
• Subjects: Actuation; Applied sciences; Electronics; Exact sciences and technology; Instruments, apparatus, components and techniques common to several branches of physics and astronomy; Liquids; Mechanical engineering. Machine design; Mechanical instruments, equipment and techniques; Media; Microelectronic fabrication (materials and surfaces technology); Micromechanical devices and systems; Multiplexing; Physics; Piezoelectricity; Precision engineering, watch making; Quality factor; Resonant frequencies; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices
• ISSN: 0960-1317; 1361-6439
• DOI: 10.1088/0960-1317/20/7/075014

In this paper, the authors report for the first time the physical cointegration of piezoelectric actuation and piezoresistive detection on resonating micromembranes dedicated to microgravimetric biosensing applications. The micromembranes are oscillated by a reverse piezoelectric phenomenon provided by a PbZrxTi1-xO3 46/54 thin layer. The oscillation amplitudes are read-out by measuring the resistance change of piezoresistors precisely located on the clamped edges of each micromembrane. The detection of the micromembranes' resonant frequencies is reported in air and deionized water. A dedicated electronic set-up operating the micromembranes in a closed-loop configuration is described. The set-up enables multiplexed tracking of four micromembranes' resonant frequencies in liquid media while enhancing the corresponding quality factors' values. Increases up to 11-fold of the micromembranes' quality factors in liquid is reported for the (0,1) vibration mode. A quality factor of up to 417 is reported in fluid.