Impact of EUV mask absorber defect with pattern-roughness on lithographic images

摘要

Impact of EUV mask absorber defect with pattern-roughness on lithographic images was studied. In order to reduce systematic line width roughness (LWR) of wafer printed pattern, mask making process was improved; and in order to reduce random LWR, low line edge roughness (LER) resist material and a CD averaging method of multiple exposure shots were introduced. Then by using a Small Field Exposure Tool (SFET), mask induced systematic printed LWR was quantified and estimated at 32nm HP and 28nm HP. The measurement results of the critical mask absorber defect size were compared with simulation; and the results are then discussed.