Everything electronic gets smaller, including sensors. Sensors are the devices that gauge your car’s tire pressure. They feel your fingers pinching an iPhone screen. They’re everywhere in modern technology, and soon they will be ultrasensitive and all but invisible – as nanosensors. There are many companies and academic laboratories working on the incorporation of nanotechnology into the realm of sensors. One recently announced development comes from Tel Aviv University (Israel), where they are working on sensors that use carbon nanotubes.

The innovation is the ability to align the nanotubes – like tiny standing strands of hair (however, only 1/100,000 the size of hair) – as the sensitivity element attached to a much larger (though still almost microscopic) MEMS (microelectromechanical system) device. The nanotubes are created in a methane atmosphere at high temperature, which creates small deformities in the crystalline structure of the tubes that have great sensitivity to movement – movement as small as a few atoms. The MEMS device is like a packaging to add the electronic inputs and outputs necessary to turn the sensitivity of the nanotubes into electronic signals. The complete package remains very small.

Another focus of the research was to make sure the nanotube/MEMS combination was easy to manufacture. This is often one of the stumbling blocks of nanotechnology. In fact, most previous nanosensors required hand-crafting techniques. This nanosensor can be manufactured with automatic systems and should be able to scale (ramp up production numbers) to meet the needs of a variety of industries.

The market for MEMS devices, which take mechanical signals and convert them into electrical impulses, is estimated to be worth billions. “The main challenge facing the industry today is to make these basic sensors a lot more sensitive, to recognize minute changes in motion and position. Obviously there is a huge interest from the military, which recognizes the navigation potential of such technologies, but there are also humanitarian and recreational uses that can come out of such military developments,” Prof. Hanein [Professor Yael Hanein, Engineering Faculty] stresses. More sensitive MEMS could play a role in guided surgery, for example.

[Source: Tel Aviv University]

The Tel Aviv University team is working on increasing the sensitivity of their current device.