Metal assisted focused-ion beam nanopatterning

Area of Science:

• Materials Science
• Nanotechnology
• Surface Engineering

Background:

• Focused-ion beam (FIB) milling is a maskless nanofabrication method.
• Nonuniform ion beams and material redeposition in FIB degrade surface morphology and pattern transfer fidelity.
• Ion-beam induced damage affects photonic device performance and nanoimprint template precision.

Purpose of the Study:

• To introduce a novel Metal-Assisted Focused-Ion Beam (MAFIB) process.
• To overcome limitations of traditional FIB milling, such as surface disfigurement and pattern fidelity loss.
• To enable high-fidelity nanopatterning and direct fabrication of features like tunable v-shaped grooves.

Main Methods:

• Utilized a removable sacrificial aluminum layer during focused-ion beam milling.
• Employed the MAFIB process on various substrates, including dielectric and metal (e.g., silver) films.
• Investigated the direct formation of v-shaped grooves with tunable angles.

Main Results:

• Achieved smooth surfaces and fine milling edges, mitigating traditional FIB issues.
• Successfully demonstrated direct formation of v-shaped grooves with tunable angles on different substrates.
• High-fidelity and reproducible nanopatterns were created on diverse materials.

Conclusions:

• The MAFIB process offers a significant advancement in nanofabrication.
• It enhances surface quality and pattern transfer accuracy compared to conventional FIB.
• MAFIB provides the capability and flexibility for fabricating advanced nanophotonic devices and nanoimprint templates.