Gas-Assisted Etching of Micro-Hole Lattice Array on Lithium Niobate with Focused Ion Beam

Two-dimensional micro-hole lattice arrays with specified structure parameters were fabricated on LiNbO_3(LN) substrate by means of focused ion beam(FIB) etching,and the influence of etching parameters,such as spot current,etching time full rate,were investaged.In order to etch good quality holes,the authors used gas-assisted etching(GAE) with focused ion beam.The results show that GAE can reduce the effect of redeposition and obtain better hole profile compared with FIB etching.According to simulative calculation,the photonic bandgap of lattice array,etched by GAE with XeF_2,is more close to the ideal photonic bandgap.