AT&T; to Share Key Element in Semiconductor

AT&T; signed an agreement Monday to share a key ingredient used to make advanced semiconductors under the auspices of Sematech, the consortium of computer chip makers formed to boost U.S. semiconductor competitiveness.

Under the agreement, American Telephone & Telegraph Co. will allow a division of Olin Corp. to make and sell a chemical used to etch extremely detailed electronic circuitry on chips.

The chemical, called “deep UV resist,” allows chip designers to pack a greater number of circuits on chips than with current technologies. In making chips, circuitry is etched on silicon wafers using a light-sensitive chemical--or resist--and a “mask,” whose function is similar to that of a negative in photography.

AT&T; Bell Laboratories of Murray Hill, N.J., has invented a version of the chemical that is used with ultraviolet light instead of the visible light now used.

UV resist can produce highly complex computer chips with circuits as thin as 0.3 micrometers, or about 400 times smaller than a human hair, AT&T; said.

Circuitry on most chips today is 1.0 to 1.2 microns wide; they reach 0.8 microns in advanced chips.