According to foreign media reports, recently, scientists of kaust company developed a micron level and low-power pressure sensor, which has potential application prospects in vacuum environment.
Nowadays, sensors are the interface between automation systems such as computers and robots and their environment. Sensors measure light, temperature, motion, mass, pressure, position, etc. at present, the demand for sensors in the market and applications is to make them smaller so that they can be integrated into portable products. For example, pressure sensors can be used in industrial control, medical care, medical testing and meteorology. According to different applications, these pressure sensors need to be sensitive to small changes, respond quickly to these changes, and work in a large pressure range.
Now, nouha alcheikh, Amal hajjaj and Mohammad Younis have developed a sensitive pressure micro sensor based on a silicon vibrating beam, which is only 800 microns long, 25 microns wide and 1.5 microns thick. “We have developed a scalable and sensitive micro pressure sensor that can work in a larger pressure range in nanosystems,” alcheikh said
In the experimental study, the suspension beam will vibrate at resonant frequency, which is determined by its mass, length, density and stiffness. When an electric current passes through the vibrating beam, it becomes hotter and begins to bend. This increased curvature increases the stiffness of the vibrating beam, thereby moving the resonant frequency. The air around the vibrating beam cools it: the higher the pressure, the more air, and the better the cooling effect. Therefore, the resonance frequency of the vibrating beam that can be measured electrically is related to the pressure. The device manufactured by the team works in a wide pressure range, from 0.038 torr to 200 Torr (atmospheric pressure is 760 Torr), and the sensitivity of the pressure sensor is 2689 x 10-6 / Torr.
The research team also showed that the pressure micro sensor can adapt to specific applications by changing the thickness of the vibrating beam. They simulated the operation of the vibrating beam to prove that the sensitivity becomes higher for the thinner micro vibrating beam, but the thicker vibrating beam consumes more energy. Therefore, the optimal thickness of the optimal sensitivity under low pressure or high pressure can be calculated according to the target environment of the device.
“Thanks to kaust’s state-of-the-art facilities, we are lucky to be able to explore some new ideas, such as this novel pressure sensor. I hope to continue to use this opportunity to commercialize this device concept,” alcheikh said