Crystal Power: Creating Electricity Through Nanotech
Researchers have successfully embedded a complex, single-crystal material with “giant” piezoelectric properties onto silicon. This resulted in the production of low-voltage, almost nano-scale electromechanical devices.
Piezoelectric materials use mechanical energy to produce electricity. On the other hand, they can also be used to convert electrical energy to mechanical motion such as they can be used to produce high-frequency acoustic waves for ultrasound imaging.
Chang-Beom Eom, a UW-Madison professor of materials science and engineering and physics, and the team members worked on lead magnesium niobate-lead titanate, or PMN-PT, which is an advanced Piezoelectric material exhibiting "giant" piezoelectric response (i.e. it can give greater mechanical displacement with the same amount of electric field as given by traditional piezoelectric materials.) The research team used potential chemical reactions among the components to incorporate them onto a silicon “platform” to form very small scale devices.
A very thin layer of strontium titanate was added onto silicon “platform”. This combination worked as a structure of silicon. Then a layer of a layer of strontium ruthenate was placed on it and at the end single-crystal piezoelectric material PzMN-PT was added. This whole combination worked in the same way as was theoretically predicted to give piezoelectric response.
This device can improve high-resolution 3D imaging, communications, signal processing, energy harvesting, sensing and actuators for nanopositioning devices.
Image: Professor Chang-Beom Eom
Image Credit: Department of Materials Science and Engineering, University of Wisconsin-Madison