November 9, 2011 — National Institute of Standards and Technology (NIST) and the University of Virginia (UVA) have demonstrated that electron microscope beams can be used to move around nanoscale objects, raising the possibility of positioning and assembling nanoelectronics.
The tool is an electron-beam version of "optical tweezers:" laser-based manipulation tools used in biology, physics, and other fields. Electron beams could offer a thousand-fold improvement in sensitivity and resolution.
The "electron tweezers" effect was discovered during observation of aluminum-silicon alloys transitioning to a molten state. The researchers saw that their electron beam was being followed around by the solid core of the AlSi particle when they moved or tilted the beam or microscope stage.
The discovery was "unexpected," said NIST metallurgist Vladimir Oleshko, because of the drawbacks of working with electrons. Future applications could include fine manipulation of particles or even atoms; electron beams are three orders of magnitude smaller than photon beams. The "electron tweezers" would require a vacuum still.
Results are published here: V.P. Oleshko and J.M. Howe. Are electron tweezers possible? Ultramicroscopy (2011) doi:10.1016/j.ultramic.2011.08.015. Access the journal at http://www.journals.elsevier.com/ultramicroscopy/.
The National Institute of Standards and Technology (NIST) is an agency of the U.S. Department of Commerce. Learn more at www.nist.gov.