Next Article in Journal
A Finger Grip Force Sensor with an Open-Pad Structure for Glove-Type Assistive Devices
Previous Article in Journal
A Robust Real-Time Detecting and Tracking Framework for Multiple Kinds of Unmarked Object
Article

Maintaining Transparency of a Heated MEMS Membrane for Enabling Long-Term Optical Measurements on Soot-Containing Exhaust Gas

1
Department of Microelectronics, Faculty of EEMCS, Delft University of Technology, Mekelweg 4, 2628CD Delft, The Netherlands
2
Chalmers University of Technology, Department of Microtechnology and Nanoscience, EMSL, Kemivågen 9, 412 58 Gothenburg, Sweden
3
Research and Advanced Engineering, Ford Motor Company, Dearborn, MI 48121, USA
*
Author to whom correspondence should be addressed.
Sensors 2020, 20(1), 3; https://doi.org/10.3390/s20010003
Received: 18 November 2019 / Revised: 13 December 2019 / Accepted: 16 December 2019 / Published: 18 December 2019
(This article belongs to the Section Physical Sensors)
Ensuring optical transparency over a wide spectral range of a window with a view into the tailpipe of the combustion engine, while it is exposed to the harsh environment of soot-containing exhaust gas, is an essential pre-requisite for introducing optical techniques for long-term monitoring of automotive emissions. Therefore, a regenerable window composed of an optically transparent polysilicon-carbide membrane with a diameter ranging from 100 µm up to 2000 µm has been fabricated in microelectromechanical systems (MEMS) technology. In the first operating mode, window transparency is periodically restored by pulsed heating of the membrane using an integrated resistor for heating to temperatures that result in oxidation of deposited soot (600–700 °C). In the second mode, the membrane is kept transparent by repelling soot particles using thermophoresis. The same integrated resistor is used to yield a temperature gradient by continuous moderate-temperature heating. Realized devices have been subjected to laboratory soot exposure experiments. Membrane temperatures exceeding 500 °C have been achieved without damage to the membrane. Moreover, heating of membranes to ΔT = 40 °C above gas temperature provides sufficient thermophoretic repulsion to prevent particle deposition and maintain transparency at high soot exposure, while non-heated identical membranes on the same die and at the same exposure are heavily contaminated. View Full-Text
Keywords: optical automotive instrumentation; optical MEMS; heated silicon carbide window; suspended membranes; on-board diagnostics; surface regeneration from soot deposits; thermophoretic repulsion of soot optical automotive instrumentation; optical MEMS; heated silicon carbide window; suspended membranes; on-board diagnostics; surface regeneration from soot deposits; thermophoretic repulsion of soot
Show Figures

Graphical abstract

MDPI and ACS Style

Middelburg, L.M.; Ghaderi, M.; Bilby, D.; Visser, J.H.; Zhang, G.Q.; Lundgren, P.; Enoksson, P.; Wolffenbuttel, R.F. Maintaining Transparency of a Heated MEMS Membrane for Enabling Long-Term Optical Measurements on Soot-Containing Exhaust Gas. Sensors 2020, 20, 3. https://doi.org/10.3390/s20010003

AMA Style

Middelburg LM, Ghaderi M, Bilby D, Visser JH, Zhang GQ, Lundgren P, Enoksson P, Wolffenbuttel RF. Maintaining Transparency of a Heated MEMS Membrane for Enabling Long-Term Optical Measurements on Soot-Containing Exhaust Gas. Sensors. 2020; 20(1):3. https://doi.org/10.3390/s20010003

Chicago/Turabian Style

Middelburg, Luke M., Mohammadamir Ghaderi, David Bilby, Jaco H. Visser, Guo Q. Zhang, Per Lundgren, Peter Enoksson, and Reinoud F. Wolffenbuttel 2020. "Maintaining Transparency of a Heated MEMS Membrane for Enabling Long-Term Optical Measurements on Soot-Containing Exhaust Gas" Sensors 20, no. 1: 3. https://doi.org/10.3390/s20010003

Find Other Styles
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Back to TopTop