Single-Atom Transistor Built

We have come a long way since Alexander Graham Bell.  Now, we are working with things that the naked eye can’t even see.  This week, the smallest working transistor ever made has been created by a team of Australian and American physicists from a single atom of phosphorus. A transistor is a tiny device that controls the flow of electric current in radios,television sets, computers, and almost every other kind of electronic equipment. By switching between “on” and “off,” transistors physically simulate the 1′s and 0′s that represent digital information. Like the transistors used in virtually all modern computer chips, the atom-sized transistor was etched into a crystal of silicon. However, significant additional development is needed before a single-atom transistor could be used in practical microprocessors because it requires temperatures well below freezing.

Since the 1960′s, chipmakers have managed to shrink transistors in half roughly once every 18 months–a trend known as Moore’s law. Microprocessors from the 1970′s had a few thousand transistors.  Modern fingernail-sized computer chips may contain billions of microscopic transistors. Such transistors may be less than a hundred atoms thick.

However, transistors and other computer components can only shrink so far–namely, to the size of an atom. Transistors work by switching electric current on and off. An electric current consists of a flow of electrons–negatively charged subatomic particles that move from atom to atom. Building a transistor from electrons would be impossible for much the same reason that building a faucet from water molecules would be impossible.

If Moore’s law holds, computer chip transistors will reach the atomic-scale limit within a few decades. Scientists believe that radically different designs are necessary to shrink computer components smaller than the atomic scale.

There’s more waiting for you at World Book Online. Share this and other science encyclopedia set with your friends and family, click here to read more about this topic from our encyclopedia set.

2 thoughts on “Single-Atom Transistor Built

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s