Chemical and mechanical properties of UV-cured nanoimprint resists and release layer interactions

Abstract

UV-curable nanoimprint resist characteristics and performance are key to controlling resist-related defects formed during template removal due to cohesive failure and strong resist-template adhesion. The debonding process is governed by both the chemical bonds that form between the template and the resist during cure, and by the structure of the resist itself which determines its elastic-plastic response under load. To gain insight to contributions from resist composition to the debonding process we examine the connection between mechanical and chemical properties of a family of methacrylate polyfunctionalized polyhedral oligomeric silsesquioxane (mPSS) containing resists to their adhesion to fluoroalkyl silane release layers. We also survey debonding of one of the mPSS formulations, an acrylate formulation and a vinyl ether formulation from as series of metal oxide and metal nitride release layers. The results show that while intrinsic storage modulus of a cured material is important, interfacial segregation of reactants in fluid resists can influence adhesive properties as well. The metal-containing release layers are shown to have generally much lower adhesion to cured resists than does a fluoroalkyl silane release layer. They present a useful alternative for template release treatments.