Journal cover Journal topic
Journal of Sensors and Sensor Systems An open-access peer-reviewed journal
Journal topic

Journal metrics

CiteScore value: 2.9
CiteScore
2.9
SNIP value: 1.056
SNIP1.056
IPP value: 1.38
IPP1.38
SJR value: 0.361
SJR0.361
Scimago H <br class='widget-line-break'>index value: 13
Scimago H
index
13
h5-index value: 13
h5-index13
Volume 4, issue 1
J. Sens. Sens. Syst., 4, 151–157, 2015
https://doi.org/10.5194/jsss-4-151-2015
© Author(s) 2015. This work is distributed under
the Creative Commons Attribution 3.0 License.

Special issue: 17th ITG/GMA-Conference on Sensors and Measurement Systems...

J. Sens. Sens. Syst., 4, 151–157, 2015
https://doi.org/10.5194/jsss-4-151-2015
© Author(s) 2015. This work is distributed under
the Creative Commons Attribution 3.0 License.

Review paper 14 Apr 2015

Review paper | 14 Apr 2015

Micro-structured electron accelerator for the mobile gas ionization sensor technology

C. M. Zimmer, K. T. Kallis, and F. J. Giebel C. M. Zimmer et al.
  • Intelligent Microsystems Institute, Faculty of Electrical Engineering and Information, Technische Universität Dortmund, Dortmund, Germany

Abstract. Mobile and economically priced gas monitoring and warning systems will become increasingly important for civil security, such as in fire brigade operations in undefined hazardous environments (Daum et al., 2006). Normally, photoionization detectors (PIDs) are used for the detection of gases. Hereby, the principle is based upon the ionization of the measured gas by photons, which are generated by a high-energetic gas discharge lamp with energy of 10–11 eV. Besides the detrimental unspecific gas detection because of the ionization of all gases with ionization potential (IP) below the provided photon energy, sensors also have a short lifetime combined with a high cost (http://www.intlsensor.com/pdf/photoionization.pdf).

This can be remedied by the concept of an electronic supported photoionization detector (ePID; Zimmer et al., 2012) consisting of a durable UV-LED with an above-positioned electron accelerator chip manufactured on a glass substrate by planar technology. Photoelectrons are extracted by UV illumination out of the bottom electrode and will be accelerated to an energy matching the ionization potential of the gas by a downstream acceleration grid. Thereby, the stable honeycomb-structured grid acts as a porous separator between the evacuated electron acceleration path due to nm scaling and the ionization area of the detector. To enhance the emitting area yielding a higher photoelectron current, the grid structure almost levitates, realized by the use of compatible planar technological processes such as reactive ion etching (RIE) and isotropic wet etching of sacrificial layers, which will be explained in detail in this paper. Furthermore, the tunability of the grid's acceleration voltage would enable a substance-specific determination of the gas composition, where the ionization of the analytes is clearly performed by photoelectrons instead of photons.

Publications Copernicus
Download
Citation