Information / Electronics & Computing

Photolithography for Chips

Light-sensitive resist and a mask let engineers print tiny transistor patterns onto silicon; Bell Labs adapts it in 1955.

Jules Andrus and Walter Bond at Bell Labs applied Kodak photoresist to semiconductor wafers in 1955, and Lathrop and Nall at the US Army developed it for transistors in the same years. All chip patterns are printed in this way, only with ever shorter light.