Fabrication of large area (0.5m2) soft moldusing roller pressing UV imprint machine
Woo Young Kim*1, Su Hyun Choi1, Seon Jun Kim1, Young Tae Cho#1
Kwang Young Kim2, Sin Kwon2, Seung Hyun Lee2, Hyun tae Kim2
Department of Mechanical Engineering, Changwon National University1
Changwon-si, Gyeongsangnam-do, 51149, South Korea
Department of Printed Electronics, Korea Institute of Machinery and Materials2
Daejeon, South Korea
E-mail: youngtae11@gmail.com

In recently, Patterning method is spotlighted that patterns have a special features such as
superhydrophobicity and superolephobicity. Representative patterning methods are Nano
Imprint Lithography and Photo Lithography. Nano Imprint Lithography, which applies resinand cures using heat or ultraviolet energy, has the advantage of being faster, simpler, and lesscostly than other patterning technologies. Therefore, this method is widely used andresearches are actively proceeding such as Roll to roll imprint lithography.
We have studies the fabrication of large area soft molds required to apply UV Nano Imprint
Lithography to Roll to roll equipment. For the large area soft mold, we used the step andrepeat method, which is a method of continuous UV Imprint Lithography using small area
mold and shadow mask to curing only pattern area.

Figure 1. Step and repeat imprint method

A pillar pattern having a diameter of 260nm and a height of 520nm was used as a submaster mold with 105×105 mm2 patterned area. Because the sub-master pattern is pillar type,imprinted mold pattern has hole arrays as shown in Figure 2.
The shadow mask was applied to fit the pattern area and the step and repeat imprint was performed. After that, hand UV curing machine was used for resin curing. For the instance, thesize of the large area soft mold is 105×945 mm2 as shown in Figure 4. As a result, because ofmanual process, align error was appeared apparently.

Figure 2. SEM images of Soft mold patternFigure 3. Schematic of step and repeat imprintUV curing module

Vision system
Roller Imprint system
Align stage

Powder break

Figure 4. Large area mold

Figure 5. Step and repeat imprint equipment

In order to reduce the align errors, roller pressing and aligning equipment was designed and realized as shown in Figure 5. Using this machine, step and repeat imprint process was p
erformed considering fine adjustment to minimize the align error. The equipment can be ap
plied to uniform pressurization by load cell (Max. 1000N). So we have thought of using theabove equipment to minimize the align error through the align camera using align mark, shown in Figure 9. Finally, the step and repeat imprint proceed as shown in Figure 9 with partial curing of the align mark using a shadow mask, and continuous imprint was made.

Figure 7. Master mold

Figure 8. Sub-master moldFigure 9. Step and repeat imprint with align markAcknowledge:
This research was supported by Industrial Technology Innovation Program Through the Ministry ofTrade, Industry & Energy (MOTIE), Korea Institute for Advancement of Technology (KIAT)(N0002310) and the Ministry of Trade, Industry & Energy(MOTIE, Korea) under Industrial
Technology Innovation Program. No.20000665, Development of ecofriendly and highly durable
surface treatment for superomniphobic substrate on the large area over 4m2.