Dutch and Belgian scientists from Imec and Holst Centre have developed a new sensor for detecting particle per million (PPM) concentrations of gases. The device uses polymer-coated microbridges in high-density arrays packed into a microchip only 9mm x 9mm in size.
From the announcement:
Imec and Holst Centre have developed a new generation of microbridges with embedded individual piezoelectric “shakers” in a high-density array with very high fabrication yield. The novel design allows for rapid coating of a range of absorbents on individual microbridges using commercial inkjet printing technology. The suspended structures vibrate individually, and changes in their modes of vibration (resonances) are monitored as an indication of vapor absorption in their coatings. Due to the very high length-to-thickness ratio of the microbridges, imec and Holst Centre’s novel gas sensor chip has a high sensitivity to low-concentration vapors. Moreover, by implementing integrated piezoelectric read-out schemes, ultra-low power operation could be demonstrated.
Current work is ongoing to integrate the structures with low-power analog read-out circuits and to demonstrate simultaneous measurements from multiple structures. This truly low-power miniaturized implementation of an e-nose technology can be used in current applications such as wine and cheese monitoring, but could in the future also help sniff-out human conditions such as asthma, lung cancer, and kidney diseases.
Images: Top: The scanning electron microscope image of a complete sensor chip (9mm x 9mm) consisting of 160 unique individually addressable micromechanical resonators, with aspect ratios (length/thickness) ranging from 140-1,500. Bottom: Closely-packed array of individually vibrated microbridge resonators can be used for separation of gases upon application of specific coatings.
Press release: Imec and Holst Centre report gas sensor chip paving the way to autonomous e-nose…
