IBM researchers at Yorktown Heights, New York say they have made and tested the world’s fastest silicon circuits using the company’s new one tenth-micron geometry transistors. The experimental supercooled parts switch in just 13 picoseconds, more than twice as fast as the best previously reported for a silicon transistor – against arounbd 150pS or so for the fastest ECL circuits in use today. IBM warns that many complex problems remain to be solved before entire chips can be made using the new transistors. The chips need to be cooled to minus 196o in liquid nitrogen, but significantly close the speed gap between silicon and Gallium Arsenide – the fastest GaAs parts switch in about 5pS. The parts are NMOS field-effect transistors, etched using electron beam lithography, and the next step will be the building of more complex CMOS parts.