Abstract
We report the use of atomic layer deposition (ALD) to produce the gas-sensitive tin dioxide film in a microhotplate gas sensor. The performance of the device was demonstrated using ethanol, acetone and acrylonitrile as model analytes. Fast response times and low drift rates of the output signal were measured, indicating a structurally stable tin dioxide film and reflecting the capabilities of ALD in gas sensor applications. Fabrication of the microhotplate using tungsten metallization and plasma deposited silicon dioxide dielectrics is also detailed.
| Original language | English |
|---|---|
| Pages (from-to) | 227-232 |
| Journal | Sensors and Actuators B: Chemical |
| Volume | 148 |
| Issue number | 1 |
| DOIs | |
| Publication status | Published - 30 Jun 2010 |
| MoE publication type | A1 Journal article-refereed |
Funding
The authors acknowledge the financial support from the Nordic Innovation Centre (project Threatgården of the “Everyday Nano” project portfolio of the Nordic MINT initiative), the Academy of Finland, and support for G.N. and D.C. from the European Social Fund via Itä-Suomen Lääninhallitus under project S 10148. Antti J. Niskanen received his Master’s degree in Chemical Engineering in 2002 from the Helsinki University of Technology, on the subject of liquid phase deposition of silicon dioxide thin films. He currently works in the Microfabrication Group of the Department of Micro and Nanosciences, and is working on his doctoral thesis. He has worked on the fabrication aspects of microhotplate gas sensors, and his current research interests center around thin film technology for electrochemiluminescent sensors. Aapo Varpula received his Master’s degree with distinction in Engineering Physics and Mathematics in 2006 from the Helsinki University of Technology (HUT) in Espoo, Finland. Since the beginning of 2006 he has been working on his doctoral thesis on metal-oxide based gas sensors in the Electron Physics Group of Department of Micro and Nanosciences at HUT, where he obtained his L.Sc. in 2009. His main research interests are the physical and chemical modelling of metal-oxide based gas sensors, development of measurement techniques of sensors, impedance spectroscopy, and characterization of sensor materials. Mikko Utriainen , Doctor of Science and Technology (chemical engineering, Helsinki University of Technology 1999). Current position: Senior Technology Adviser at Tekes, Finnish Funding Agency for Technology and Innovation (since 2008) and in Employment and Economic Development Centre for North Savo, Kuopio that provides Tekes’s services in North Savo region. His specialty is research, technology and innovations in the field of security and safety. Before current position Mikko was R&D manager in Environics Oy 2000–2008 specializing in sensor technology development for CBRNE security area. Before Environics he was carrying out solid state chemical sensor research in the Helsinki University of Technology and wrote his D.Sc. thesis of the same topic. Gomathi Natarajan received her Master’s degree in Materials Science in the year 2002 from PSG College of Technology, Coimbatore, India. In 2007, she received her Ph.D. from Dublin City University, Ireland on “Novel UV emitting layers lattice matched with Si”. Her research interests include deposition and analysis of functional thin films. She is presently working as a Humboldt guest scientist at RWTH Aachen University, Germany. David Cameron obtained his bachelor’s degree in Electronics and Electrical Engineering in 1972 from the University of Glasgow. After working in industry, he returned to the University of Glasgow and received his Ph.D. in 1980. He was a Senior Research Fellow at the Royal Signals and Radar Establishment (UK) before joining the School of Electronic Engineering of Dublin City University in 1982 where he became Associate Professor. He joined Lappeenranta University of Technology as Professor of Materials Technology in 2004. His research has been in thin film deposition: magnetron sputtering, atomic layer deposition and plasma CVD. Sergey Novikov received his Master degree in Physical chemistry from Leningrad Institute of Technology (USSR) in 1982. He obtained his Ph.D. from the A. F. Ioffe Institute (St. Petersburg, Russia) in 1994 on the growth and characterization of the alkali-earth fluorides on silicon and gallium arsenide. Since 1995 he is working in the Helsinki University of Technology, where he is currently the senior research scientist. His main field of interest is growth of II–IV compounds and epitaxial oxides. Veli-Matti Airaksinen is the Director of the Nanofabrication Centre of Aalto University at Micronova, Finland’s leading research centre in microelectronics and nanotechnology. Dr. Airaksinen obtained his M.Sc. in Technical Physics at Helsinki University of Technology and Ph.D. in Electrical Engineering at Glasgow University. Between 1987 and 1995 he worked at the Department of Electrical Engineering of Helsinki University of Technology, studying mainly the epitaxial growth of III–V semiconductors. From 1995 to 2003 he worked for Okmetic Oyj as a Senior Scientist, developing epitaxial silicon wafers. He has held his current position since 2003. Juha Sinkkonen (M.Sc. 1967, D.Sc. 1976) has been Professor in the Electron Physics Group of Department of Micro and Nanosciences, Helsinki University of Technology (Finland) since 1984. He is specialized in semiconductor and device physics. Currently he is interested in physico-chemical characterization of semiconductor surfaces and interfaces. Sami Franssila studied physics and chemistry at the University of Helsinki and obtained B.Sc. and M.Sc. degrees in 1985 and 1986. His Ph.D. degree is from Helsinki University of Technology, School of Electrical Engineering (1995) with a thesis on plasma etching. He worked as a research scientist at VTT Microelectronics from 1986 till 1998, with 1993–1994 at IMEC, Belgium, and since 1998 at Helsinki University of Technology. He has worked on CMOS, MEMS and microfluidic devices and has published 80 peer reviewed journal articles and a textbook “Introduction to Microfabrication”. He is currently a Professor of Materials Science, with research interests in materials and fabrication technologies for fluidic, bio, chemical and thermal devices, and flexible electronics.
Keywords
- Atomic layer deposition
- Metal-oxide gas sensor
- Microhotplate gas sensor
- Tin dioxide