Replication of polyethylene terephthalate (PET) nano/micro structures using ultrasonic nanoimprint

The ultrasonic nanoimprint lithography (U-NIL) were proposed to overcome the drawbacks of energy consumption and long process times comparing with conventional NIL methods. However, the relationship between process condition and imprinting quality has not been completely and systematically investigated. Therefore, it is necessary to study on the optimal process parameters to get good replicated structures in imprinting process. In this study, we have demonstrated the replication nano- and micro- structures on polyethylene terephthalate (PET) in heating-assisted ultrasonic nanoimprint. A highly effective tool of the Taguchi method has been utilized to acquire the optimal process parameters. Using the filling ratio as imprinting quality, the results of orthogonal array experimental layout could determine the optimal process parameters as the best setting. The confirmation test with these optimal parameters shows good filling ration of 96.40 % in replication structures from silicon mold to PET film with high formability and good imprinting quality. This would provide to advance U-NIL and to achieve nano- or micro- structures replication with high throughput and low cost.