Highly miniaturized pressure sensors have been fabricated by scientists at The University of Manchester with the help of graphene membranes capable of detecting small changes in pressure with high sensitivity, over an extensive range of operating pressures.
Writing in Nanoscale, Dr. Aravind Vijayaraghavan and recently graduated PhD student Dr. Christian Berger have demonstrated the possibility of making a one atom thin membrane of graphene float only nanometers above the surface of a silicon chip.
When pressure pushes this membrane closer to the chip’s surface, the subsequent change in capacitance is then measured in order to read out the change in pressure. A device can be developed with incredibly high sensitivity to pressure changes by fabricating thousands of the afore mentioned floating membranes close to each other.
Graphene is considered to be the world’s first two-dimensional material. The design takes advantage of its surprising thinness, incorporated with its great flexibility and the highest strength of any known material; such a technology is important to bring about a unique combination of superlative properties.
We use this graphene membrane in conjunction with a very thin polymer support layer, which allows us to produce thousands of floating graphene membranes closely packed into a small area, resulting in this highest performance pressure sensor. Despite its amazing strength, a single atomic layer thin graphene membrane is impossible to grow and handle without causing cracks and pin-holes, which would lead to the failure of the device. In order to overcome this, we use this graphene membrane in conjunction with a very thin polymer support layer, which allows us to produce thousands of floating graphene membranes closely packed into a small area, resulting in this highest performance pressure sensor.
Dr. Aravind Vijayaraghavan, The University of Manchester
Dr. Vijayaraghavan and Dr. Berger have together established a spinout company, Atomic Mechanics, as they aim to commercialize this technology. Recently, Dr. Berger and Daniel Melendrez-Armada, fellow PhD student, were also awarded the Eli and Britt Harari Graphene Enterprise award for their concept on the touch interface based on this pressure-sensor technology.
Dr. Berger said: “Our sensor can find a range of applications, such as in engines, industrial plants and even household Heating, ventilation, and air conditioning (HVAC) systems, which offers us a large market. The technology can also be used to develop next-generation touch screens for consumer electronics and in new types of medical devices.”