Abstract: Two-dimensional micro-hole lattice arrays with specified structure parameters were fabricated on LiNbO₃ (LN) substrateby 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 XeF₂, is more close to the ideal photonic bandgap.

Key words: focused ion beam, lithiumniobate, gas-assisted etching

摘要： 使用聚焦粒子束(FIB) 在LiNbO₃上刻蚀用于光子晶体的亚微米圆孔二维点阵, 研究了刻蚀束流、刻蚀时间和填充率等刻蚀参数对刻蚀结果造成的影响。为获得更好的刻蚀效果, 还采用了FIB的气体辅助刻蚀方法(gas-assisted etching , GAE) 。研究发现,与直接刻蚀结果相比,GAE 减小了反沉积效应, 得到了更好的孔形。禁带模拟计算表明, 与常规FIB 刻蚀出的锥形圆孔相比, 使用XeF₂气体辅助刻蚀得到的这种侧壁更陡直的圆孔阵列构成的光子晶体禁带更趋近于理想光子晶体的禁带。

关键词: 聚焦离子束, 铌酸锂, 气体辅助刻蚀