Application of focused ion beam technology for fabrication of photonic nanostructures

摘要

We report our recent results on focused ion beam (FIB) nano-structuring of Bragg gratings in both, amorphous AI2O3 and crystalline KY(WO4)2 channel waveguides. By optimizing FIB milling parameters such as ion current, dwell time, loop repetitions, scanning strategy, and improving sidewall definition, reflection gratings with smooth and uniform sidewalls are achieved. The redeposition effects are significantly reduced and gratings more than 4 um in depth with an improved total sidewall angle of about 5° are achieved by varying dwell time and pixel resolution distribution for the same dose per area.