. | . |
Researchers create tiny sensor using 'white graphene' by Brooks Hays Washington (UPI) Jun 28, 2017 Researchers have developed a new method for creating tiny mechanical sensors using "white graphene." The sensor is made by placing white graphene, a 2D atomic sheet of hexagonal boron nitride, over the minuscule holes in a silicon substrate. Scientists say the material could serve as tiny gas and pressure sensors inside electronics. The hexagonal structure of white graphene is similar to that of regular graphene, but the atomic layer is made up of boron nitride, the compound of boron and nitrogen, instead of carbon. Graphene is prized for its conductive qualities, but hexagonal boron nitride, or h-BN, works as an insulator. White graphene is also more chemically and electrically stable than graphene, allowing it to function under more extreme circumstances, like in space. Until, scientists have struggled to develop a scaleable way to make 2D layers of h-BN. Layers of graphene are easily exfoliated from graphite, but h-BN layers stick to one another. "There are only two or three institutions in the world that can produce single, two-dimensional layers of white graphite, and the University of Cambridge is one of them," lead researcher Santiago J. Cartamil-Bueno said in a news release. "This project is a success thanks to our effective collaboration with them." Cambridge scientists used a method called chemical vapor deposition to deposit single layers of hexagonal boron nitride on a sheet of iron foil. Scientists at Delft University of Technology in the Netherlands used the white graphene layers from Cambridge to build the miniature sensors. By placing the white graphene over tiny cavities in a silicon substrate, researchers created tiny drums that work like mechanical resonators. During the sensor-production process, scientists realized the drums were being contaminated by the polymer, making each drum-turned-sensor behavior slightly differently. Precision and consistency are essential to mechanical sensors. Researchers found that by treating the drums with ozone, they could rid the sensors of imperfections. "Fortunately, this problem can be solved by only using organic substrates while transferring the sheet of white graphite onto the cavities," said Cartamil-Bueno. Researchers detailed their breakthrough this week in the journal Nature. The next step is for scientist to incorporate the tiny sensors into actual electronics.
Washington DC (SPX) Jun 28, 2017 Modulating the amplitude and phase of light is a key ingredient for many of applications such as wavefront shaping, transformation optics, phased arrays, modulators and sensors. Performing this task with high efficiency and small footprint is a major challenge for the development of optoelectronic devices. In a recent paper published in Nature Photonics, ICFO researchers Dr. Achim Woessner ... read more Related Links Carbon Worlds - where graphite, diamond, amorphous, fullerenes meet
|
|
The content herein, unless otherwise known to be public domain, are Copyright 1995-2024 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. All articles labeled "by Staff Writers" include reports supplied to Space Media Network by industry news wires, PR agencies, corporate press officers and the like. Such articles are individually curated and edited by Space Media Network staff on the basis of the report's information value to our industry and professional readership. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. General Data Protection Regulation (GDPR) Statement Our advertisers use various cookies and the like to deliver the best ad banner available at one time. All network advertising suppliers have GDPR policies (Legitimate Interest) that conform with EU regulations for data collection. By using our websites you consent to cookie based advertising. If you do not agree with this then you must stop using the websites from May 25, 2018. Privacy Statement. Additional information can be found here at About Us. |