Polyvinyl alcohol: a high-resolution hydrogel resist for humidity-sensitive micro-/nanostructure

Area of Science:

• Materials Science
• Nanotechnology
• Polymer Chemistry

Background:

• Advancements in hydrogel nanodevices necessitate high-resolution nanopatterning techniques.
• Polyvinyl alcohol (PVA) is a widely used polymeric hydrogel with potential for nanofabrication.

Purpose of the Study:

• To develop and demonstrate a high-resolution nanopatterning technique using PVA as a negative-tone resist for electron beam lithography (EBL).
• To evaluate the resolution capability and functional properties of PVA nanopatterns.

Main Methods:

• Utilized PVA as a negative-tone resist in EBL.
• Established an aqueous nanopatterning process involving dissolution, spin-coating, and development.
• Characterized the resolution of the fabricated patterns.

Main Results:

• Achieved a resolution as fine as 50 nm half-pitch using PVA as an EBL resist.
• Demonstrated that PVA's hydrophilic groups remain stable post-EBL, preserving humidity responsiveness.
• Developed a solvent-free, aqueous-based process suitable for organic device fabrication.

Conclusions:

• PVA is a viable negative-tone resist for high-resolution EBL nanopatterning.
• The developed aqueous process is efficient and environmentally friendly.
• This technique facilitates the future design and fabrication of advanced hydrogel-based nanodevices.