Silicon-microbeam chemical microsensors to monitor air quality and detect explosives.
Project: Silicon-microbeam chemical microsensors to monitor air quality and detect explosives.
Establishments: Laboratory of Integration from Materials to Systems - University of Bordeaux.
Research themes: Safety
For the duration of: 2007/2009
Project leader: Sébastien Tétin, project student.
Link: www.ims-bordeaux.fr
Descriptive: This project involved developing a dedicated autonomous handheld system using chemical MEMS (Micro Electro Mechanical System) micro sensors, which detect a wide variety of analytes.
The sensing platform's design involves using silicon microbeams paired with sensitive layers to selectively retain targets (sensor selectivity depends on the target application).
These systems can be used in applications such as early chemical or bacteriological pollution detection. In gas-detecting systems, a layer senses target gas molecules that alter the beam's behavior. The options to detect surface density encompass limiting sources of noise and increasing sensitivity.
This study has shown that it was possible to optimize beam design to improve sensitivity to variation (in fluid density, in particular).
This principle can therefore be used on a system to monitor fluid density, which can branch into several applications, namely:
- Producing constant-density gas or other fluid mixes
- Using fluid density to ascertain concentration of one component in a binary mixture (provided both components are known)
Interview:
« Le projet financé par la Fondation EADS a donné lieu à ma soutenance de thèse. Ila permis d'étudier des micropoutres en tant que microcapteurs et de définir différents modes d'utilisation. Avec ou sans couche sensible, l'utilisation de ces microcapteurs repose sur des principes différents. Je pense que ce type de capteurs chimiques prendra une place importante dans le futur. La Fondation a suivi le déroulé du projet et le suivi de ma thèse ».
Sébastien Tetin, project student.