Solutions for 22-nm node patterning using ArFi technology

ArF immersion lithography will be the main candidate for lithography patterning at the 22nm node. For both logic and memory type applications, double patterning techniques have to be applied to reach design pitches well below 70nm. In the lithography this combines aggressive imaging at low k1 (0.28... 0.31) and aggressive absolute CDU requirements (approximately 6-10% of nominal CD) of 1.5..2nm 3σ. We will look into the lithography requirements to achieve such aggressive CDU numbers and will discuss solutions for achieving the required level of intra-field, inter-field, waferto- wafer and scanner-to-scanner CD variations