Photoluminescence from silicon quantum dots in Si quantum dots/amorphous SiC superlattice

We prepared size-controlled silicon quantum dots superlattices (Si-QDSLs) by thermal annealing of stoichiometric hydrogenated amorphous silicon carbide (a-SiC:H)/silicon-rich hydrogenated amorphous silicon carbide (a-Si1+xC:H) multilayers. Transmission electron microscope (TEM) observation revealed that silicon quantum dots were formed, in only a-Si1+xC:H layers. The size of silicon quantum dots can be controlled by the thickness of the a-Si1+xC:H layers. It was found that hydrogen plasma treatment (HPT) significantly enhanced the photoluminescence of the Si-QDSLs. The luminescence peaks shifted to shorter wavelength with decreasing the diameter of the silicon quantum dots in the Si-QDSL.