Investigation of Optical Properties and Photoluminescence of Amorphous Silicon Carbide in a-SiC/Si_3N_4 Quantum Well Structures Fabricated by PECVD Technique

摘要

a-SiC:H/a-Si_3N_4:H multilayer quantum well structures have been fabricated using the PECVD technique. It consists of 16 alternating layers of a-SiC (～2 and 4 nm thick) as the well layers and a-Si_3N_4:H as the barrier layers. The multilayer structures of the samples have been verified using TEM micrographs. The samples were studied using the spectroscopic ellipsometry (SE) and photoluminescence (PL) techniques. The SE data for the multilayers have been successfully fitted, from which the optical properties of the thin a-SiC layer have been determined. The effects of quantum confinement on the absorption coefficients and refractive indices of a-SiC:H have been investigated. The results are correlated to the PL spectra of the samples.