Hydrodynamics and solid mechanics structural analysis of mold deformation in nanoimprint lithography

Abstract

A hybrid model has been developed to study the dynamic filling process of the resist and to investigate the subsequent capillary force induced structural deformation of the imprint mold during nanoimprint lithography (NIL). The dynamic behavior of resist filling with varied physical parameters was investigated by a hydrodynamic model. The capillary force induced deformation of mold structures was modeled using beam bending mechanics for various mold structures. Theoretically calculated results were cross-validated with finite-element simulations using fluid–structure interaction and two-phase flow methods. Based on the theoretical analysis, a general parameter of critical aspect ratio is proposed as the guideline for the design of NIL mold, especially for the NIL mold with a high aspect ratio and ultra-high resolution. The theoretical investigation helps to deepen the understanding of the dynamic mechanism of resist filling and structural deformation, and enables the optimization for high-fidelity NIL.