THE WAY TO ONE QUARTER MICROMETER PHOTOLITHOGRAPHY

To investigate the way to achieve 250nm photolithography, aerial image simulations are performed. Simulation results show that expected depth of focus will be very shallow even using KrF(248nm) wavelength with conventional illumination system. To enlarge the depth of focus, progress of resist performances, resolution enhancement technologies and mask biases are required. In this paper, we will outline the importance of resist performance and mask bias, and explain the influence of Resolution Enhencement Technologies.