In the nanotechnology realm, pocket change figures big.
Dan Pickard, a graduate student at Stanford University's electrical-engineering school, needed a diamond membrane for an e-beam lithography system that can be used to help create nanotech products.
The slides in the accompanying photo gallery chronologically demonstrate how, with the help of professor Fabian Pease and undergraduate Heyjin Park, Pikard extracted the membrane from a diamond chip with a focused ion beam, a probe and an electron microscope. The diamond chip is about a millimeter in diameter and about 20 microns thick. The membrane is about 20 microns a side and 200 nanometers to 500 nanometers thick.
An e-beam lithography system draws a pattern on the surface of a semiconductor wafer that eventually becomes transistors or areas where metals or carbon can be grown. The energy from the beam imprints a copy of a mask--a sort of stencil--onto the surface of the wafer, which consists of layers of silicon and metal. That imprint is then exposed through processes similar to those used in photographic development. In traditional chips, the result is transistors. In nanotechnology, the result might be particles of iron, which can serve as a catalyst for growing carbon.
The rise of nanotechnology has increased the importance of complex electrons and probes and made equipment makers some of the first beneficiaries of nanotechnology. FEI, which produced the equipment used in the images, reported fourth-quarter revenue of $145.2 million, an increase of 49 percent over revenue of $97.7 million a year ago. Net income rose to $8.4 million, more than the $3.3 million reported a year ago.
Although the resulting membrane in Pickard's work can be measured in microns, it's actually relatively large in nanotech terms. E-beam systems, meanwhile, are expected to play a large role in preparing surfaces for growing nanoparticles.
And what's up with the pocket change? It serves as a backdrop and workbench of sorts for the process depicted in the photos.