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

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, 120nm, to around 100nm by intentionally introducing radical quenchers in the resin. The roughness measured from 10μm×10μm surface areas were averaged to 4–11nm, 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.