Perfluoropolyether (PFPE) Intermediate Molds for High-Resolution Thermal Nanoimprint Lithography

Area of Science:

• Materials Science
• Nanotechnology
• Soft Lithography

Background:

• Thermal Nanoimprint Lithography (NIL) is a high-throughput, low-cost soft lithography technique for thermoplastic materials.
• Conventional NIL molds (silicon, nickel, quartz) are expensive, difficult to fabricate at high resolution, and degrade over time.
• Existing methods face challenges in mold durability and high-fidelity pattern replication for nanoscale features.

Purpose of the Study:

• To introduce and characterize an innovative two-step NIL process utilizing a perfluoropolyether (PFPE) intermediate mold.
• To evaluate the performance of PFPE molds compared to standard polydimethylsiloxane (PDMS) molds for sub-100 nm feature replication.
• To demonstrate enhanced resolution, fidelity, and master mold preservation in NIL processes.

Main Methods:

• A two-step NIL process was developed using a PFPE intermediate mold to replicate patterns from a silicon master mold.
• PFPE molds were characterized and compared with polydimethylsiloxane (PDMS) molds for their ability to replicate sub-100 nm features.
• The resolution, fidelity, and durability of the PFPE intermediate mold process were assessed.

Main Results:

• The PFPE intermediate mold demonstrated superior resolution and fidelity in replicating sub-100 nm features compared to PDMS molds.
• The two-step NIL process using PFPE molds effectively preserved the nanostructured silicon master molds.
• Significant enhancement in the overall throughput of the nanoimprint lithography process was achieved.

Conclusions:

• The developed two-step NIL process with PFPE intermediate molds offers a viable solution for high-fidelity, cost-effective nanoimprinting.
• PFPE molds provide a durable and effective alternative to conventional NIL mold materials, extending the lifespan of master molds.
• This innovative approach significantly improves the efficiency and preserves the integrity of nanoscale pattern replication in thermoplastic materials.