Abstract
Thermal nanoimprint lithography is playing a vital role in fabricating micro/nanostructures on polymer materials by the advantages of low cost, high throughput, and high resolution. However, a typical thermal nanoimprint process usually takes tens of minutes due to the relatively low heating and cooling rate in the thermal imprint cycle. In this study, we developed an induction heating apparatus for the thermal imprint with a mold made of ferromagnetic material, nickel. By applying an external high-frequency alternating magnetic field, heat was generated by the eddy currents and magnetic hysteresis losses of the ferromagnetic nickel mold at high speed. Once the external alternating magnetic field was cut off, the system would cool down fast owe to the small thermal capacity of the nickel mold; thus, providing a high heating and cooling rate for the thermal nanoimprint process. In this paper, nanostructures were successfully replicated onto polymer sheets with the scale of 4-inch diameter within 5 min.
Highlights
There has been growing interest in the fabrication of micro/nanostructures on flexible substrates for a variety of burgeoning applications such as flexible supercapacitor [1,2], optical elements [3,4], electronic skin [5,6,7], wearable biosensors [8,9,10,11], virtual reality (VR) devices [12], augmented reality (AR) devices [13,14,15], etc
Nanoholes array with a pitch of 600 nm, diameter of 300 nm, and depth of 250 nm, were successfully replicated onto poly(methyl methacrylate) (PMMA) sheets in the scale of 4-inch diameter by thermal nanoimprint lithography through induction heating of nickel mold
This research demonstrated the feasibility of a rapid thermal nanoimprint process by developing a thermal imprint apparatus through induction heating of a nickel mold or blank nickel sheet
Summary
There has been growing interest in the fabrication of micro/nanostructures on flexible substrates for a variety of burgeoning applications such as flexible supercapacitor [1,2], optical elements [3,4], electronic skin [5,6,7], wearable biosensors [8,9,10,11], virtual reality (VR) devices [12], augmented reality (AR) devices [13,14,15], etc. As the pre-polymer cross-links, nanopatterns corresponding to the mold are formed on the polymer surface [29] Both T-NIL and UV-NIL have the advantages of low cost, high throughput, and high resolution. Once the external alternating current is cut off, the heating process is terminated and the temperature of the nickel mold will fall fast due to its small thermal capacity, providing a high heating and cooling rate for the thermal nanoimprint process [40,57]. If we place a blank nickel sheet on a mold of other types such as silicon mold, quartz mold, or anodic aluminum oxide (AAO) mold, heat can be generated by the blank nickel sheet and transferred to the imprint materials In this manner, it can break through the limitation of using only nickel mold, making the induction heating method more versatile
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
