High aspect ratio nanochannel machining using single shot femtosecond Bessel beams

TLDR

High‑aspect‑ratio nanochannels in glass are fabricated with single‑shot femtosecond Bessel beams of sub‑3 µJ pulse energies at 800 nm. The technique yields near‑parallel nanochannels 200–800 nm in diameter with aspect ratios exceeding 100, reproducibly produces 230 nm channels spaced 1.6 µm apart for periodic structures, and can machine a 400 nm through‑channel in a 43 µm membrane, marking a significant advance of femtosecond laser ablation into the nanometric regime.

Abstract

We report high aspect ratio nanochannel fabrication in glass using single-shot femtosecond Bessel beams of sub-3 μJ pulse energies at 800 nm. We obtain near-parallel nanochannels with diameters in the range 200–800 nm, and aspect ratios that can exceed 100. An array of 230 nm diameter channels with 1.6 μm pitch illustrates the reproducibility of this approach and the potential for writing periodic structures. We also report proof-of-principle machining of a through-channel of 400 nm diameter in a 43 μm thick membrane. These results represent a significant advance of femtosecond laser ablation technology into the nanometric regime.