Toward a Compact Wireless Surface Acoustic Wave Pirani Microsensor with Extended Range and Sensitivity

Abstract

A wireless vacuum sensor based on the Pirani principle and Surface Acoustic Waves (SAW) has been designed, simulated and manufactured. The sensing unit is a heat conductivity gauge based on a passive SAW temperature sensor. The required heating energy is applied to the sensor by means of inductive coupling whereas the measurement signal is sent via a ceramic antenna. The sensor is a compact polymer cube containing all the units and operating completely wireless. Simulation was used to design and optimize the behavior of the sensor in vacuum and to predict the performances of the sensor. It was followed by the manufacturing and the assembly of a prototype. This communication presents the design, the simulation results and the manufacturing steps of the prototype.

Additional information

Funding

The authors would like to acknowledge the financial support provided by the EU network program H2020 under Grant MIGRATE No. 643095.

Notes on contributors

Sofia Toto

Sofia Toto is a Ph.D. student at the Karlsruhe Institute of Technology. Her thesis focuses on the development of a wireless vacuum SAW Pirani microsensors. She studied Mechanical Engineering at the Ecole Centrale de Nantes in France. In 2018, she was awarded the Elsevier Student Award for her research work during the European Vacuum Conference (EVC15) in Geneva. Her research interests include sensors, semiconductor technology and wireless telecommunications.

Pascal Nicolay

Pascal Nicolay received a B.S. degree in physics from Grenoble University in 1999, an Engineering Diploma from the Institut National Polytechnique de Lorraine in 2001 (ENSGSI), an M.S. degree in plasma physics, optics, electronics, and microsystems from Nancy University in 2004, and a Ph.D. degree in physics from Nancy University in 2007. From 2001 to 2004, he worked for the French Agency for Innovation (OSEO-ANVAR). He joined the LPMIA, Nancy, France as a Ph.D. student in 2004, where he worked on surface acoustic wave sensors, mainly for applications in the fields of high-temperature measurement and lowpressure monitoring. This work was made in collaboration with Doerler Mesures SA, in order to develop innovative and commercializable products. He is now with the Carinthia University of Applied Sciences, as a SAW researcher. He is currently interested in the modeling, design, and applications of electromechanical SAW components.

Gian Luca Morini

Gian Luca Morini graduated in Nuclear Engineering in 1992 and received a Ph.D. in Nuclear Engineering in 1996 from University of Bologna. He started as Assistant Professor at University of Ferrara in 1996. Since 2002 up to 2012, he was Associate Professor in Applied Thermal Engineering at the University of Bologna. Since 2005 he is Head of the Applied Thermal Engineering Laboratory of the DIN. He is author of 180 technical papers related to the Thermal Engineering and Heat Transfer.

Achim Voigt

Achim Voigt finished his degree as Diploma Engineer Physical Technology in 1991. He integrated the Karlsruhe Nuclear Research Center in 1992 and worked as Research and Development engineer for developing SAW based Gas and Bio Sensor Systems. Since 2006 he is at the Institute for Microstructure Technology (IMT) for engineering support of scientists and Ph.D. students. He took part to 10 KIT patents and owns one private patent.

Jan G. Korvink

Jan G. Korvink received his M.Sc. degree in mechanical engineering (specializing in computational mechanics) from the University of Cape Town, South Africa, in 1987, and his Ph.D. degree from the ETH-Zurich, Switzerland, in 1993. After completing graduation, he joined the Physical Electronics Laboratory, ETH Zurich. In 1997, he joined the University of Freiburg, Freiburg, Germany, as full professor for microsystems engineering. In Freiburg he co-directed the Freiburg Institute for Advanced Studies (FRIAS). In 2015 he joined the Karlsruhe Institute of Technology, where, besides directing the Institute of Microstructure Technology, he also acts as one of the speakers of the Helmholtz Program” Science and Technology of Nanosystems”. He is the author or coauthor of more than 200 technical publications in the broad area of microsystems. He is a founding Editor of Advanced Micro and Nanosystems, and the co-founder of two successful startup companies. His research interests include the development of ultralow-cost micromanufacturing methods, microsystem applications in the area of magnetic resonance imaging, and the design and simulation of micro- and nanosystems. He was the recipient of a Red Dot Design Concept Award in 2011, and a European Research Council Advanced Grant in the area of micro NMR metabolomics for the nematode C. elegans.

Juergen J. Brandner

Juergen J. Brandner studied Chemistry at University of Heidelberg and Electrical Engineering at Technical University of Karlsruhe (T.H.). He obtained his diploma in Electrical Engineering at the Technical University of Karlsruhe (T.H.) in cooperation with the Alternative Microstructuring Methods Research Group of the Karlsruhe Research Center. He obtained his Ph.D. in Mechanical Engineering from the Technical University of Karlsruhe (T.H.) with research on Fast Temperature Cycling of heterogeneously catalyzed gas phase reactions in microstructure devices. He is currently a lecturer for Micro Process Engineering at Dresden Technical University. He received his Habilitation and Venia legendi in Micro Process Engineering at Dresden Technical University.