Nanostructured sensors have uses in safety, environmental monitoring, fire detection, and security.
Standard microfabrication techniques can be implemented and scaled to help assemble nanoscale microsensors. Currently nanostructures are often deposited onto materials primarily by adding them to a solution, then applying the solution in a thin film. This results in random placement of the nanostructures with no controlled order, and no way to accurately reproduce the placement. This method changes the means by which microsensors with nanostructures are fabricated. The fundamental advantage to this approach is that it enables standard microfabrication techniques to be applied in the repeated manufacture of nanostructured sensors on a microplatform.
This buries the contacts of the nanostructures that are bridging the fingers between two layers of metal. The result is a microsensor fabricated using microfabrication techniques with aligned nanostructures bridging the electrodes and buried electrical contacts.
Possible applications include emissions monitoring, leak detection, engine monitoring, security, fire detection, extravehicular-activity (EVA) applications, personal health monitoring, and environmental monitoring. Because this process is compatible with low temperatures and thin-film supports, it can be used in thin films for conductive coatings requiring electrical connections.
A proof-of-concept of this approach was demonstrated using alumina as the substrate, metals such as platinum as the bottom electrode and titanium as the top metal layer, and both multiwalled carbon nanotubes and metal oxide nanowires as the nanostructured material.
This work was done by Gary W. Hunter, Randall L. VanderWal, Laura J. Evans, and Jennifer C. Xu of Glenn Research Center. For more information, download the Technical Support Package (free white paper) at www.techbriefs.com/tsp under the Manufacturing & Prototyping category.
Inquiries concerning rights for the commercial use of this invention should be addressed to NASA Glenn Research Center, Innovative Partnerships Office, Attn: Steve Fedor, Mail Stop 4–8, 21000 Brookpark Road, Cleveland, Ohio 44135. Refer to LEW-18418-1.