Studies on optical properties and fabrication of microtube in group Ⅲ-Nitride semiconductors using PEC etching

Abstract

Microstructures with various shapes are actively studied in the field of optics and have been recognized for their versatility and efficiency. Among them, three-dimensional tube structures have been used in various fields because of their effective interaction with surrounding media, spatial overlap between field regions and structures and ease of shape and size modulation. In this study, only a specific material was removed selectively in nitride semiconductors with different bandgap through the photoelectrochemical etching, and the tube structure was fabricated by strain relaxation. It was confirmed that the tube structure was relaxed under the compressive strain originated from the substrate causing the shift in the PL and Raman mode. The strain variation according to the position on the tube was stronger toward the center of the tube, and the change was slightly decreased at the edge. In addition, it was confirmed that the polarization characteristic appeared in the tube structure compared with the non-polarization in planar structure. From the results of this study, it is expected to be widely applied as a new platform of optical structure by controlling wavelength modulation and polarization degree and direction in single tube structure.