Micro sensors for extreme conditions

Miniaturised sensors are nothing new, but ones made from a combination of silicon carbide (SiC) and the single-layer lattice of carbon atoms known as graphene certainly are. These new sensors are being designed to operate under the harshest of conditions.

Tiny structures etched into graphene-silicon carbide wafers, will be used in micro sensors for a variety of applications
Tiny structures etched into graphene-silicon carbide wafers, will be used in micro sensors for a variety of applications. Credit: QMF/GU

Research, led by the Australian National Fabrication Facility’s (ANFF) Queensland node at Griffith University, promises a new generation of tiny microelectromechanical system (MEMS) sensors that are sensitive to very low forces, can work at high frequencies and in extreme conditions—above 1,000°C or under an acceleration of several times g—and are resistant to chemical attack.

“We see applications in accelerometers and gyroscopes for aerospace and automotive uses, as well as in the harsh environments of mining and deep sea exploration,” says Dr Francesca Iacopi of the Queensland Micro and Nanotechnology Facility (QMF) at Griffith University. “There’s also potential for high-sensitivity biological sensors; for instance, blood monitoring and pressure sensing.”

The idea for the new graphene-SiC technology came out of an ANFF meeting with US Air Force scientists, and is founded on the “outstanding mechanical properties of graphene, the fact that graphene can be synthesised on SiC, and our capability of easily making microbeams and membranes with our silicon carbide-on-silicon technology, which is a core QMF capability,” says Francesca.

Research on the SiC MEMS began about two years ago, while the graphene-SiC MEMS work is only months old.

“The research is still in its early stages. If successful, however, it may get to market quite rapidly… five years as a rough estimate,” says Francesca.

ANFF has been instrumental in bringing together and leveraging the expertise, technologies and needs of Griffith University, QMF, the Queensland State Government and the US Air Force laboratories.

Photo: Tiny structures etched into graphene-silicon carbide wafers, will be used in micro sensors for a variety of applications.
Credit: QMF/GU

Queensland Micro and Nanotechnology Centre, Griffith University, Francesca Iacopi, Tel: +61 7 3735 8014, f.iacopi@griffith.edu.au, www.griffith.edu.au/engineering-information-technology/queensland-microtechnology-facility, www.griffith.edu.au/science-aviation/queensland-micro-nanotechnology-centre/staff/dr-francesca-iacopi