Progress and outlook of lithography for semiconductor IC

Progress of lithography from the lensless type to lens-based systems using different kinds of photon and electron beams is reported here. The stages of lithography development with their physical principles are linked to the corresponding impacts to IC designers to help them understand the reasons they are more and more restricted. From this vantage point, we look at the prospects of the lithography systems that will handle patterning for 32-nm half pitch and beyond in feasibility and cost.