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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

The most common type of modern transistor, and the type of transistor used in integrated circuits, is called a field-effect transistor (FET). The FET is so named because it relies on an electric field to control the shape and hence the conductivity of a 'channel' (the charge carrier) in a semiconductor material. This field causes a second electrical current to flow across the semiconductor, identical to the first weak signal, but stronger.

Since the invention of the first transistor in 1947, the vast majority of electronic devices have been based on inorganic semiconductors, which in most cases has been silicon. Due to the demand for lightweight, flexible opto-electronic devices such as displays, solar cells and lasers, organic materials have become an important new class of semiconductor as they combine the virtues of plastics, which can be easily shaped, with those of semiconductors which are the basis of all microelectronics.

Source: http://www.nanowerk.com/spotlight/spotid=5168.php