Sub-10-nanometer-scale laser ablation on hard materials from dielectric near-field nanophotonics

Abstract

This paper demonstrates sub-10-nanometer (nm) laser ablation on hard materials. An 800-nm-wavelength femtosecond laser is focused down to sub-diffraction-limited scale by a silicon nanophotonic structure fabricated on a silicon-on-isolator (SOI) substrate, which is utilized to enable the ablation on the silicon dioxide (SiO2) layer of the SOI. Atomic force microscopy (AFM) results show a minimum ablation linewidth of about 8 nm with a depth-to-width ratio close to 1.