Analysis of Debonding Problem during Demolding Process of Nanoimprinting

Abstract

Template release process during nanoimprint lithography was investigated, and the detailed steps of this process were described in order to reduce defects caused by demolding process. The debonding problem was discussed by using optimization of model, numerical simulation and theoretical analysis. The rules and mechanism of debonding were obtained by analyzing the relations between the bonding strength and the vertical stresses of the cementing surface linking the residual layer and the substrate in terms of stress balance theory in fracture mechanics. The location and demolding process which is prone to debond were analyzed. It is concluded that the debonding phenomenon took place at the intermediate position during the second demolding stage, when the adhesion force between the resist and the mold was 0.8 times of other interfaces between the mold and the resist. The debonding phenomenon took place at the angular position during the fourth demolding stage, when the adhesion force between the resist and the mold was 1.2 times bigger than the other interfaces between the mold and the resist.

Effects of Ultraviolet Intensity and Initial Thickness on Normal Force of Acrylic Ultraviolet Curable Resin

“…A detaching force from a NIL mold, which may be related to the residual force, has also been measured using a device where a force sensor was attached to the NIL mold [14]. The numerical simulation of the NIL process, taking shrinkage into account, has also been developed by Hirai's group [15][16][17][18] and another group [19]. Moreover, in the fields of additive manufacturing or three-dimensional (3D) printing using UV-curable resins, residual stress, and shrinkage are major concerns [20].…”