High precision lithography for submicron VLSI fabrication

In order to accomplish submicron VLSI lithography using a variable shaped electron beam direct writing technology, a novel mark detection method and a linewidth compensation technique using newly developed submicron resists have been developed. This method and technique have been applied to the submicron VLSI manufacturing process with 0.6µm minimum pattern size, aiming at mega bit level d-RAM fabrication. Accuracy of ±0.1µm for overlay and 0.05µm deviation in linewidth have been achieved.