Fabrications of Photonic Bandgap Structures in Si and Ge Substrates Using Laser-Assisted Nanoimprinting of Self-Assembled Nanoparticles

摘要

The fabrications of periodic dielectric structures at nanoscales, which are called photonic bandgap (PBG) structures, have attracted the interests of researchers due to the applications in a variety of fields such as optoelectronics, photonics, sensors, photo catalysts, and energy harvesting coatings. One- and two-dimensional PBG structures have been realized because such systems are very amenable to conventional fabrication techniques. However, three-dimensional (3-D) PBG structures are still remained as an important and motivating challenge. This project aimed at the fabrication of 3-D PBG structures with laser-assisted processing techniques. Theoretical simulation and experimental measurements for optical properties of PBG structures were also carried out. The morphologies, material properties, and optical properties of the PBG structures were characterized using scanning electron microscopy (SEM), Raman spectroscopy (RS), and spectroscopic ellipsometry (SE). It has been proved that 3-D PBG structures with expected optical properties can be obtained using laser-assisted processing techniques.