an improved template fabrication process utilizing photoresist as mold material was developed
which started with a direct casting of polydimethylsiloxane(PDMS)onto the photoresist mold pattern generated by direct electron beam writing. The process variables affecting the molding process and the transferring patterns were analyzed
the photoresist mold pattern and the PDMS template pattern were observed by scanning electron microscopy(SEM). The results show that the features of the PDMS template are only related to the molding pressure and the strength of the photoresist mold is enough to resist the molding pressure under 0.05 Pa in the vacuum casting. The replication accuracy of soft template generated by the photoresist mold gets(97.24±0.60)% and the square root of the accuracy approaches to 0.376%. The photoresist pattern remains unstained and undamaged after casting PDMS onto it for 50 times. As a result
the process adopting photoresist as mold material enables to improve the throughput of soft UV nanoimprint lithography with a lower cost.
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references
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