Anisotropic properties of pipe-GaN distributed Bragg reflectors.
Chia-Jung WuYi-Yun ChenCheng-Jie WangGuo-Yi ShiuChin-Han HuangHeng-Jui LiuHsiang ChenYung-Sen LinChia-Feng LinJung HanPublished in: Nanoscale advances (2020)
We report here a simple and robust process to convert periodic Si-doped GaN/undoped-GaN epitaxial layers into a porous-GaN/u-GaN distributed Bragg reflector (DBR) structure and demonstrate its material properties in a high-reflectance epitaxial reflector. Directional pipe-GaN layers with anisotropic optical properties were formed from n + -GaN : Si layers in a stacked structure through a lateral and doping-selective electrochemical etching process. Central wavelengths of the polarized reflectance spectra were measured to be 473 nm and 457 nm for the pipe-GaN reflector when the direction of the linear polarizer was along and perpendicular to the pipe-GaN structure. The DBR reflector with directional pipe-GaN layers has the potential for a high efficiency polarized light source and vertical cavity surface emitting laser applications.