| 초록 |
Due to the huge difference between the refractive index of GaN and air, there have been a lot of efforts to minimize the reflection at the interface. Surface roughening by photoelectrochemical etching showed promising results but the reproducibility is still a major issue. Nanopattering using electron beam lithography and focused ion beam have been reported, but they are not practical for the mass production. So, we used the block copolymer template to fabricate the nanostructures on GaN surface. We adapted the triblock copolymers, PS-b-PMMA-b-PEO. It was shown that nanostructured patterns with vertically oriented PEO/PMMA cylinders can be produced via solvent annealing, and the nanoporous templates can be prepared by UV irradiation. Inductively Coupled Plasma was employed to etch the surface of GaN using 30 sccm of Cl2 and 5 sccm of BCl3. The etch rate of triblock copolymer was carefully calibrated and it was confirmed that nano-patterns were successfully transferred to GaN. |
