EUV Patterning Strategy compensating EUV Shot Noise

Abstract

It is reported that EUV shot noise has become fundamental issues to deteriorate LWR (Line Width Roughness) and CDU (CD Uniformity). But progress of EUV source power is delayed and not sufficient, we need to develop EUV patterning technology to overcome EUV shot noise. Currently there are four technological strategies and we are investigating them. ; These are (1) resist upgrade, (2) additional LWR / CDU mitigation process, (3) EUV NTD (Negative Tone Development) and finally (4) blend DSA (Directed Self Assembly) rectification. Resist upgrade and additional LWR / CDU mitigation process is matured more or less, so we are using some effects from them already. But EUV NTD and blend DSA rectification is new and potential technology which is introduced recently, so we expect these will become break-through technologies against EUV shot noise.