Influence of the surrounding host in obtaining tunable and strong visible photoluminescence from silicon nanoparticles

摘要

We have investigated the influence of the microstructure and chemistry of the surrounding host on the strong visible photoluminescence (PL) from silicon nanoclusters (nc-Si) embedded in three different silicon-based dielectric compounds: Si_xN_y:H,Cl, Si_xN_yO_z:H,Cl, and Si_xO_Z:H,Cl, obtained from silicon nitride films deposited by SiH_2Cl_2/NH_3/H_2 plasma-enhanced chemical vapor deposition at different growth pressures. A blueshift is found in the PL coming from the nc-Si as the content of oxygen in the surrounding host is increased, and a significant improvement in PL intensity is achieved when the nc-Si are well passivated with O instead of H. We discuss the PL behavior in terms of the quantum confinement model and passivation state of the nc-Si surface.