Ultrasonics for nanoimprint lithography

In this paper we demonstrate that ultrasonic nanoimprint lithography (U-NIL) method can overcome the drawbacks of energy consumption and long process time occurred in conventional nanoimprint lithography (NIL) methods. Instead of using heaters in conventional NIL, the proposed U-NIL employs ultrasonic vibrations located on the top of mold to generate high frequency vibrations to soften and to melt the thermoplastic polymer. The temperature of polymer can rise rapidly for ultrasonic vibrations with frequency of 27 kHz. A simple but novel imprint apparatus has been designed for feasibility study of our U-NIL system. The experimental results showed that vibratory energy could increase temperature of the polymer in transferring the topography of mold´s surface into the polymer. We conclude that the proposed U-NIL process has the potential to become a novel nanoimprint method with high productivity, energy efficiency, and low cost.