KrF lithography for 130 nm

As ArF lithography continues to mature, it can be expected that, KrF lithography combined with reticle and illumination enhancements will be preferred techniques, for cost- effective 130-nm node, in particular for low-end microprocessors, random logic and DRAM designs. There are tow main enhancement routes to extend KrF lithography. The first one entails the use of alternating phase shift masks.