Theory and simulations of peel demolding for large-area nanoimprint lithography

Abstract

Nanoimprint lithography (NIL) is an emerging nanopatterning approach for producing large-area micro/nano scale structures with low cost, high throughput and high resolution. Demolding has now been considered as one of the most challenging issues for large area NIL, and a bottleneck hindering the industrialization of full wafer NIL. Peel demolding mode has been proven to be an effective way implementing large area nanoimprinting. This paper investigated the theoretical model and numerical simulation of peel demolding for large are NIL. A general model estimating demolding force was established based on the combination of the strain energy method and the conservation of energy in demolding stage. The required separating force for vertical demolding of grating patterns was achieved using the proposed model. Furthermore, the influence of the properties of mold materials and the aspect ratio of feature patterns for peel demolding was revealed by numerical simulation using ABAQUS software. These findings are valuable in providing a theoretical basis for large area NIL, optimizing demolding process and further enhancing the performance of full wafer NIL tool.