Record-breaking transistor, robot.

In 40 years, computers have shrunk from the size of a room to that of a phone book. This miniaturization has been made possible by ever tinier components and ever more precise manufacturing technologies. Last month, scientists pushed the limits even further by introducing the world's smallest transistor and an extremely dexterous robot.

The new metal-oxide semiconductor field-effect transistor packs its active area -- 1/75,000 the cross-section of a human hair -- into a space 1/20 the size of any previous transistor, according to Clive M. Reeves and his colleagues at the IBM Thomas J. Watson Research Center in Yorktown Heights, N.Y. The largest memory chips today can store about 16 megabits of information, but this new transistor should enable engineers to pack 4 gigabits of memory into a single chip, the researchers reported in Orlando, Fla., at the 36th International Symposium on Electron, Ion and Photon Beams.

To make a robot that could build better computer packages and circuit boards, IBM's Ralph L. Hollis built a high-speed micro-robot hand that can position parts to within 0.2 micrometer, increasing robotic precision more than 100-fold. This "fine positioner" contains just one stationary part and one moving armature, which face each other. Compressed air keeps the two parts separate and allows the armature to move without rubbing against the stationary part. A computer-driven electromagnetic field then controls vertical, horizontal and rotational motion of tools held in the armature. IBM uses this robot at several factories, says Hollis, who described the new device at the IEEE International Conference on Robotics and Automation in Nice, France.