Conference paper
Combined Colorimetric and Gravimetric CMUT Sensor for Detection of Phenylacetone
Department of Micro- and Nanotechnology, Technical University of Denmark1
MEMS-AppliedSensors, Department of Micro- and Nanotechnology, Technical University of Denmark2
Surface Engineering, Department of Micro- and Nanotechnology, Technical University of Denmark3
Colloids and Biological Interfaces, Department of Micro- and Nanotechnology, Technical University of Denmark4
The detection of phenylacetone is of interest as it is a common precursor for the synthesis of (meth)amphetamine. Resonant gravimetric sensors can be used to detect the mass and hereby the concentration of a gas while colorimetric arrays typically have an exceptional selectivity to the target analyte if the right colorimetric dyes are chosen.
We present a sensor system consisting of a Capacitive Micromachined Ultrasonic Transducer (CMUT) and a colorimetric array for detection of phenylacetone. The CMUT is used as a resonant gravimetric gas sensor where the resonance frequency shift due to mass loading of the plate. A single Local Oxidation of Silicon (LOCOS) step was used to define the cavities which were sealed with a Si3N4 plate with a thickness of 100nm, resulting in a resonance frequency of 38:8MHz and a theoretical mass sensitivity of 28:3 zg/Hz·μ2.
The CMUTs were functionalized with the same dyes used to fabricate colorimetric arrays. While both the CMUTs and the colorimetric arrays showed selectivity to phenylacetone, the best selectivity was achieved by the colorimetric array. Furthermore, the mass of the phenylacetone was found as a function of time.
Thus, the combination of the colorimetric array and the CMUT results in a good selectivity and a quantitative value for the mass.
| Language: | English |
|---|---|
| Publisher: | IEEE |
| Year: | 2017 |
| Pages: | 1-1 |
| Proceedings: | 2017 IEEE International Ultrasonics Symposium |
| ISBN: | 1538633825 , 1538633833 , 1538633841 , 9781538633823 , 9781538633830 and 9781538633847 |
| ISSN: | 19485727 |
| Types: | Conference paper |
| DOI: | 10.1109/ULTSYM.2017.8091676 |
| ORCIDs: | Mølgaard, Mathias Johannes Grøndahl , Thygesen, Ida Lysgaard , Jakobsen, Mogens Havsteen , Andresen, Thomas Lars and Thomsen, Erik Vilain |
(meth)amphetamine Cavity resonators Coatings Color Drugs Government LOCOS step Resonant frequency Sensitivity Si-Si<sub>3</sub>N<sub>4</sub> Silicon Substrates Time-frequency analysis capacitance measurement capacitive micromachined ultrasonic transducer capacitive sensors colorimetric CMUT sensor colorimetric array colorimetric dyes colorimetry density measurement elemental semiconductors frequency 8.0 MHz gas sensors gravimetric CMUT sensor local oxidation of silicon step mass detection micromachining microsensors organic compounds oxidation phenylacetone detection resonance frequency shift resonant gravimetric gas sensor sealing sensor arrays silicon silicon compounds size 100.0 nm ultrasonic transducer arrays weighing
