X-ray photoelectron spectroscopy of GaSb nanoparticles embedded in SiO_2 matrices by radio-frequency magnetron co-sputtering

摘要

GaSb-SiO_2 composite films were fabricated by radio-frequency magnetron co-sputtering. Transmission electron microscope (TEM) results exhibit that the GaSb nanoparticles were uniformly dispersed in SiO_2 matrices. The sizes of nanoparticles are in the range of 4-10 nm. X-ray photoelectron spectroscopy (XPS) analysis confirms the high purity of GaSb nanoparticles contained in the SiO_2 matrices and shows that the GaSb and SiO_2 exist in nonstoichiometry in the composite films due to the strong affinity of Sb and Si with oxygen. Room temperature optical transmission spectra show a very large blue shift of about 2.76 eV with respect to that of bulk GaSb, suggesting the existence of quantum size effects.