Novel technologies in coater/developer to improve the defectivity for advanced EUV patterning materials

The application of metal-oxide resist (MOR) for mass production is highly expected since MOR has an advantage of higher resolution. However, the metal components itself has a high risks of metal contamination and the defects based on metal components. Therefore, control of defects is more important than conventional chemically amplified resist (CAR). In this paper, reduction of defect densities are examined by latest technologies in the coater/developer. As results, on pillar pattern, many fall-on and scum defects were observed and majority of them were transferred to underlayer by etching process. In order to reduce the fall-on and the scum defects, three possible solutions were proposed. First, the latest resist supply system was designed for MOR. In addition, particles emitted from the latest supply system was reduced compared to the conventional system. Second, improvement of purity of the developer solution contributed to the reduction of fall-on particles. Third, application of the optimized rinse after development reduced 12% of the scum defect on the pillar pattern after lithography. It contributed to 19% (single bridge) and 18% (multi bridge) reduction after etching process. Furthermore, the optimized rinse reduced the single bridges on the line and space (L/S) pattern by 14% after etching process. These proposed three technologies are expected to be utilized for high volume manufacturing.