Structures Analysis And Photoluminescence Properties Of Amorphous SiN_xO_y Films Prepared By Magnetron Sputtering

The development of optoelectronic integration needs Si-based light-emitting materials.Bulk silicon has an indirect energy bandage and therefore is highly inefficient as a light source,necessitating the use of other materials for this purpose,which allows highly efficient and stable Si-based light-emitting material to have become a hot spot.SiN_xO_y film possesses excellent physical properties and electro-optical performance,so it has become the candidate of light-emitting silicon-based materials.In this paper,amorphous SiN_xO_y films were deposited on p-Si substrate by magnetron sputtering technology in a constant sputtering power and substrate temperature,with the different flow ratio.Then the samples were annealed in the N₂ atmosphere at high temperature.By FTIR spectra and PL spectra,we find that the spectra of the annealed samples exists a strong absorption band between 500cm^-1 and 1500cm^-1,and the absorption band is considered of the Si-N bond and Si-O-Si bond stretching vibration absorption;The annealed samples have a strong PL peak in the visible light spectra between 300nm and 800nm,and with the annealing temperature increasing,the intensity of light-emitting peak decreases gradually.Keep the nitrogen flow ratio constant,with the oxygen flow ratio increasing,the thin film is SiO₂-rich Si₃N₄ film,the light-emitting of the film can be attributed to the NOV defect (O₃≡Si-Si≡O₃).Keep the oxygen flow ratio constant,with the nitrogen flow ratio increasing,the thin film is Si₃N₄-rich SiO₂ film,the light-emitting of the thin film can be from nc-Si₃N₄.According to Robertson's theory,we believe that the light-emitting of nc-Si₃N₄ can be attributed to the electronic emission transition of E_c→≡Si⁰(5.3eV→3.1 eV) or E_c→≡Si^-(5.30eV→3.40eV).