Influence of annealing conditions on the chemical states of InP/SiO 2 nanocomposite films deposited by rf magnetron co-sputtering

Indium phosphide/silica composite thin films have been fabricated on water-cooled substrates and heated substrates respectively by radio frequency magnetron cosputtering technique. X ray diffraction patterns and optical absorption and photoluminescence spectra at room temperature strongly suggest that InP nanocrystals exist in the SiO 2 matrices of the films deposited on water-cooled substrates after annealing and of the films deposited on heated substrates. X-ray photoelectron spectra show that there are quite a log of oxides of In and P and quite many oxygen deficiencies of SiO 2 in the films deposited on water-cooled substrates, but there are few deficiencies of SiO 2 and much less oxides of In and P in the films deposited on heated substrates. The component of InP increases and the oxides of In and P and oxygen deficiencies in SiO 2 diminish at a large extent under suitable annealing temperature and time in a high vacuum system, but the role of annealing is limited because of the escape of P. The problem can be solved quite well by coating a SiO 2 layer on the surfaces of the films before annealing and then annealing the films in H 2 of 10 3 Pa.