Direct laser writing on silicon surface for large area nanoplasmonic devices

The present work use direct laser writing (DLW) system for fabrication of large area patterning of microstructures. Micro sized square pattern of 1μm size with 2μm spacing were successfully fabricated on 1500 x 1500 μm² large area Si substrate. The developed microstructures found potential application in colloidal nanotweezers manipulation of plasmonic devices. The results shows precision in large scale micro patterning using DLW system and claimed a faster and simple process in patterning microstructure compared to electron beam (e-beam) lithography process. The developed micro patterning are dry etched using RIE to convert SiO₂ pillar of 500 nm height with tip diameter of 250 nm to fabricate the helical structures which found potential applications in nanoplasmonic devices.