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Recently, at Arizona State University's Biodesign Institute, N.J. Tao and collaborators have found a way to make a key electronic component on a phenomenally tiny scale. Their single-molecule diode is described in this week's online edition of Nature Chemistry.

In the electronics world, diodes are a versatile and ubiquitous component. Appearing in many shapes and sizes, they are used in an endless array of devices and are essential ingredients for the semiconductor industry. Making components including diodes smaller, cheaper, faster and more efficient has been the holy grail of an exploding electronics field, now probing the nanoscale realm.

Smaller size means cheaper cost and better performance for electronic devices. The first generation computer CPU used a few thousand transistors, Tao says noting the steep advance of silicon technology. "Now even simple, cheap computers use millions of transistors on a single chip."

Source: http://www.sciencedaily.com/releases/2009/10/091013110042.htm

Most chemical elements become superconducting at low temperatures or high pressures, but until now, copper, silver, gold, and the semiconductor germanium, for example, have all refused superconductivity. Scientists at the Forschungszentrum Dresden-Rossendorf (FZD) research center were now able to produce superconducting germanium for the first time. Furthermore, they could unravel a few of the mysteries which come along with superconducting semiconductors.

Superconductors are substances that conduct electricity without losses when cooled down to very low temperatures. Pure semiconductors, like silicon or germanium, are almost non-conducting at low temperatures, but transform into conducting materials after doping with foreign atoms. An established method of doping is ion implantation (ions = charged atoms) by which foreign ions are embedded into the crystal lattice of a semiconductor.

To produce a superconducting semiconductor, an extreme amount of foreign atoms are necessary, even more than the substance would usually be able to absorb. At the FZD, germanium samples were doped with about six gallium atoms per 100 germanium atoms. With these experiments, the scientists could prove indeed that the doped germanium layer of only sixty nanometers thickness became superconducting, and not just the clusters of foreign atoms which could easily form during extreme doping .

Source: http://www.sciencedaily.com/releases/2009/05/090528092520.htm

Researchers at the National Institute of Standards and Technology (NIST) have set the stage for building the “evolutionary link” between the microelectronics of today built from semiconductor compounds and future generations of devices made largely from complex organic molecules. In an upcoming paper in the Journal of the American Chemical Society,* a NIST team demonstrates that a single layer of organic molecules can be assembled on the same sort of substrate used in conventional microchips.

The ability to use a silicon crystal substrate that is compatible with the industry-standard CMOS (complementary metal oxide semiconductor) manufacturing technology paves the way for hybrid CMOS-molecular device circuitry—the necessary precursor to a “beyond CMOS” totally molecular technology—to be fabricated in the near future.

Source: http://www.eurekalert.org/pub_releases/2008-03/nios-ntp031808.php