Advanced PFAS-Free Surface Modifying Treatment (SMT) and Sublimation Drying Agents for Pattern Collapse Prevention

As miniaturization progresses, pattern collapse during drying has become a critical issue. We have previously demonstrated that PK-HUZ is an effective SMT agent for preventing pattern collapse. However, PK-HUZ contains PFAS components. In this study, we developed a PFAS-free SMT agent and evaluated its performance. By optimizing the process conditions, uniformity was improved, and the PFAS-free agent PK-HN1 demonstrated equivalent effectiveness to PK-HUZ. In addition, we developed a sublimation drying agent as a promising approach for pattern collapse prevention. The PFAS-free sublimation drying agent PK-L3 demonstrated excellent collapse prevention performance, even for pillar patterns with stiffness below 40 mN/m – conditions under which SMT is typically less effective. Furthermore, the short processing time highlights PK-L3’s potential as an effective solution for single-wafer drying processes.