Impact of curing kinetics and materials properties on imprint characteristics of resists for UV nanoimprint lithography

UV curable resist formulations for nanoimprint must satisfy criteria for cure rate, volatility, viscosity, cohesion of the cured material and release from the template in addition to being successfully imprintable. We describe an investigation of the properties of a series of formulations comprising polyhedral oligomeric silsesquioxane and selected diluents as candidates for imprintable dielectrics. Although all have low viscosity and volatility and are successfully imprinted, significant variations in cure rate, mechanical and adhesion properties with resist composition are found. The trends observed are not all predictable from the literature, indicating that formulation optimization for this application requires a focus on the fundamentals of both materials and processes.