Developments to Watch
SHINE AND RISE: HOW TO GET RID OF CHIP DUST
Will levitation be high tech's next marvel? Could be. But you'll have to look closely to see it. Radiance Services Co., a Bethesda (Md.) supplier to the semiconductor industry, is developing levitation mainly for lifting microdust off silicon wafers.
The circuit lines printed on chips are so small that microscopic dirt specks can be as obliterating as a landslide on a mountain road. Despite cleanliness procedures that make hospitals seem like pig pens, semiconductor plants often toss out 10% to 30% of their chips because of contamination. Part of the reason is that today's cleaning techniques generally miss particles smaller than 0.3 microns, says Radiance President Donna R. Fitzpatrick.
To avoid such defects, she suggests putting microdust under a spotlight. Hitting it with the right wavelength of laser light excites enough atoms to make the particles quiver and break loose. Then they're whisked away on a flow of inert gas. A demonstration line is being installed at the Defense Dept.'s
Microelectronics Research Laboratory in Columbia, Md.EDITED BY OTIS PORT