A More Sensitive Sensor

Electro-mechanical sensors tell the airbag in your car to inflate and rotate your iPhone screen to match your position on the couch. Now a research group of Tel Aviv University's Faculty of Engineering is making the technology even more useful.

Prof. Yael Hanein, Dr. Slava Krylov and their doctoral student Assaf Ya'akobovitz have set out to make sensors for microelectromechanical systems (MEMS) significantly more sensitive and reliable than they are today. And they're shrinking their work to nano-size to do it.

More sensitive sensors means more thrilling videogames, better functioning prosthetic limbs, cars that can detect collisions and dangerous turns before they occur, and — in the defense industry — missiles that can reach a target far more precisely.

Miniscule earthquakes

Able to "feel" and sense the movement of individual atoms, the researchers' new MEMS sensing device uses small carbon tubes, nano in size — about one-billionth of a meter long. Creating these tiny tubes using a process involving methane gas and a furnace, Prof. Hanein has developed a method whereby they arrange themselves on a surface of a silicon chip to accurately sense tiny movements and changes in gravity.

In the device developed by Prof. Hanein's and Dr. Krylov's team, a very tiny nanometer scale tube is added onto much larger micrometer-scale MEMS devices. Small deformities in the crystal structure of the tubes register a change in the movement of the nano object, and deliver the amplitude of the movement through an electrical impulse. "It's such a tiny thing," Prof. Hanein says. "But at our resolution, we are able to feel the motion of objects as small as a few atoms."

"Originally developed mainly for the car industry, miniature sensors are all around us," says Prof. Hanein. "We've been able to fabricate a new device where the nano structures are put onto a big surface — and they can be arranged in a process that doesn't require human intervention, so they're easier to manufacture. We can drive these nano-sensing tubes to wherever we need them to go, which could be very convenient and cost-effective across a broad spectrum of industries." ...

via American Friends of Tel Aviv University: A More Sensitive Sensor.