Lasers in lithography: A race against time

R. Winn Hardin, Senior News Editor

In the 1970s, the scientific community believed that optical lithography could not create microcircuits on semiconductors with features smaller than 1.25 mm. It was wrong.
Today, with the help of excimer lasers and improved multielement lens designs, Intel's Pentium Pro series has critical feature dimensions of 0.25 mm. Motorola Semicondcutor produces 0.18-mm channels on microchips for the latest Macintosh computers and expects to go to 0.15 mm next year.
Below 0.15 mm, new laser systems await improvements to multielement optical systems that do not absorb deep UV radiation. Even further away, approximately seven short years, scientists and manufacturers question whether optical lithography will be able to produce feature sizes of 0.1 mm and below.