Defectivity and CD uniformity improvement in resist coating and developing process in EUV lithography process

Extreme ultraviolet lithography (EUVL) technology is getting closer to high volume manufacturing phase every year. In order to enhance the yield of EUV lithography processing, further improvement of defectivity and CD uniformity is required at the moment. In our previous report in 2017, we have exhibited the defectivity reduction by applying our new rinse and dispense system to a 24nm contact hole (CH) pattern. On the basis of the knowledge received through that evaluation, further study for improvement of the defectivity has been investigated in this paper. As a result of further optimization of the rinse process, 83 % further reduction of residue defect from the result reported previously is achieved. Also, CD uniformity control is a very crucial factor towards EUVL manufacturing phase. We have exposed 15 wafer batches continuously for both line/space and contact hole patterns in order to confirm the current status of wafer to wafer (WTW) as well as field to field (FTF), die to die (DTD), and local uniformity. Now further work for improving CD stability is ongoing based on the results from this first trial.