Simple and Robust Microfabrication of Polymeric Piezoelectric Resonating MEMS Mass Sensors

• Main Authors: Cretu, E. (Author), Ge, C. (Author)
• Format: Article
• Language: English
• Published: MDPI 2022
• Subjects: adhesive lamination; Adhesive lamination; Adhesives; Costs; laser micromachining; Laser micro-machining; Laser-micromachining; mass sensor; Mass sensor; Microfabrication; Microsensors; Natural frequencies; piezoelectric MEMS; Piezoelectric MEMS; Piezoelectricity; Pollution control; polymeric thin-film MEMS; Polymeric thin-film MEMS; Polymeric thin-films; PVDF-TrFE; resonating MEMS; Resonating MEMS; Simple++; Water quality
• Online Access: View Fulltext in Publisher

 Resonating MEMS mass sensors are microdevices with broad applications in fields such as bioscience and biochemistry. Their advantageous surface-to-volume ratio makes their resonant frequency highly sensitive to variations in their mass induced by surface depositions. Recent global challenges, such as water quality monitoring or pandemic containment, have increased the need for low-cost (even disposable), rapidly fabricated microdevices as suitable detectors. Resonant MEMS mass sensors are among the best candidates. This paper introduces a simple and robust fabrication of polymeric piezoelectric resonating MEMS mass sensors. The microfabrication technology replaces the traditional layer-by-layer micromachining techniques with laser micromachining to gain extra simplicity. Membrane-based resonant sensors have been fabricated to test the technology. Their characterization results have proven that the technology is robust with good reproducibility (around 2% batch level variations in the resonant frequency). Initial tests for the MEMS mass sensors’ sensitivity have indicated a sensitivity of 340 Hz/ng. The concept could be a starting point for developing low-cost MEMS sensing solutions for pandemic control, health examination, and pollution monitoring. © 2022 by the authors. Licensee MDPI, Basel, Switzerland.