WEST LAFAYETTE, Ind. A new research platform uses a laser to measure the "nanomechanical" properties of tiny structures undergoing stress and heating, an approach likely to yield insights to improve designs for microelectronics and batteries.
This new technique, called nanomechanical Raman spectroscopy, reveals information about how heating and the surface stress of microscale structures affect their mechanical properties. Researchers have discussed the merits of surface-stress influence on mechanical properties for decades. However, the nanomechanical Raman spectroscopy has offered the first such measurement, said Vikas Tomar, an associate professor in Purdue's School of Aeronautics and Astronautics.
Surface stress is similar to the surface tension that allows small insects to walk on water, makes water drops spherical, and causes human skin to initially resist a needle's penetration. On the relatively large scale of ordinary, everyday machines, surface stress is negligible, but it becomes critical for micro- and nanostructures, he said.
Recent findings are potentially important because silicon structures measured on the scale of micrometers and nanometers form essential components of semiconductor processors, sensors and an emerging class of miniscule machines called microelectromechanical systems.
"The functioning of such devices has been found to be highly affected by their operating temperature," Tomar said. "Such densely packaged devices generate considerable heat during operation. However, until now we have not been able to measure how heating and surface stress contribute to mechanical properties."
Information about the platform and new research findings were detailed in three papers published this year. The most recent appeared Aug. 15 in the Journal of Applied Physics. Tomar has led the research with former doctoral student Ming Gan, who has graduated and is now working in industry, and current doctoral student Yan
|Contact: Emil Venere|