Improved spatial resolution and surface roughness in photopolymerization-based laser nanowriting

Abstract

The fundamental issues on the smallest possible processing accuracy and the best feasible surface smoothness in pinpoint polymerization-based laser fabrication were experimentally investigated. The lateral spatial resolution is improved from the previously reported value, $120\mathrm{nm}$ , to around $100\mathrm{nm}$ by intentionally introducing radical quenchers in the resin. The roughness measured from $10\mu \mathrm{m}\times 10\mu \mathrm{m}$ surface areas were averaged to $4–11\mathrm{nm}$ , which is found slightly affected by the laser pulse energy but independent on the scanning pitch when it is smaller than a critical value. The surface quality of this level could fully satisfy the requirement of various photonic elements and devices.