Spin coating has been used as a photoresist application method for many years,[1,2] and it has continued to include applications such as the tri-layer with stacked photoresist, Si containing anti-reflected coating (Si-ARC), and Spin on Carbon (SOC). Last year we reported EUV defectivity improvement, but the causes of some defect types were not found.[3,4] In this study, the defects unique to the coated organic film were detected using an LS9300 by Hitachi High-Technologies, and some of these defects were able to be mitigated by optimizing the SOKUDO-DUO track system. Utilizing these systems in tandem, we have revealed a mechanism of EUV pattern defect reduction linked to novel detected film coating defects. During the conference, we will discuss expansion of this concept to other film coatings.