The world’s smallest particle sensor

In Europe alone, more than 400,000 people die each year due to exposure to fine particulate matter. A tiny, energy-efficient measuring sensor for mobile devices could save lives over the long term.

The world’s smallest sensor is the size of two one-cent coins stacked on top of each other. It is a feature that makes it something more than simply very energy efficient. With dimensions of 12 mm by 9 mm by 3 mm, it fits nicely into smartphones, smartwatches and fitness bracelets. For the very first time, the devices can continuously monitor ambient air and immediately react if the amount of fine particulate matter reaches dangerous levels. Joggers and individuals headed to work could then avoid the most problematic areas.

The sensor could be used in a similar way in local applications at home or during outdoor activities, times when the device can provide an unheard of amount of data. This data could also serve as the basis for other regulatory measures and raise people’s awareness levels about the problem of fine particulate matter.

Low priced and tiny

Paul Maierhofer is the expert behind this “puny” innovation. He developed it while working on his dissertation at the Technical University of Graz in Austria along with specialists from the semiconductor maker ams and researchers at Silicon Austria Labs (SAL). The “Graz” particle sensor fills a gap. Until its invention, tightly meshed, national monitoring of air quality was foundering, the victim of the size, complexity and cost of measuring sensors available at the time.

In their project, the researchers drew on the well-known processes used in conventional measuring equipment as well as state-of-the-art production and integration methods. At this degree of miniaturization, the sensor has bumped up against the limits of the physically and technically feasible. The price sought by the semiconductor maker ams should be significantly below that of currently available products.