Micro-Raman spectroscopy investigation of the electron beam irradiation of LiNbO3 surface for 2D photonic band gap grating inscription

We report the investigation of the physical phenomena which occur in LiNbO3 during its surface irradiation by electron beam (EB) in order to fabricate 2D photonic band gap (PBG) grating. In order to better understand the mechanism of unusual holes formation by post-chemical etching, the induced micro structural modifications are studied by means of micro-Raman microscopy. We carried out EB bombardment on substrates of congruent z-cut lithium niobate. The main objective consists of the optimization of PBG grating fabrication process for applications in the field of optical telecommunications.