Novel neutral under layer materials to enhance the photolithography performance and defectivity for chemo-epitaxy process

Neutral layer (NL) material is one of the key materials for aligning block-co-polymer (BCP). In this study, NLs were designed and investigated, which have the capability to enhance the photo-lithography performance, a good alignment performance of BCP, and reduce the defectivity after chemo-epitaxy process. In order to enhance the photo-lithography performance, some new polymers were prepared with chromophores to control n/k value and adhesive unit interacted with the photo resist. The surface energy of these materials was adjusted to the neutral for BCP by controlling the ratio of chromophore and adhesion unit. The defects were also investigated and achieved low defectivity by optimized materials. Since this material has the above properties, it shows a good perpendicularly alignment pattern of BCP and a photolithography performance.