Papers by Keyword: Defect Photoluminescence

Abstract: Si and Ge ions are implanted into SiO₂ thin films, subsequently the annealing treatment are carried out. The samples exhibit photoluminescence (PL) peaks at 400, 470, 550 and 780 nm. With the annealing temperature increasing, the intensity of 400-470 nm PL band increases remarkably. After oxidation annealing treatment, the intensity of 400-470 nm PL band decreases, and that of 550 nm and 780 nm PL peaks rises. Combing with the results of X-ray photoelectron spectroscopy(XPS), X-ray diffraction (XRD) and PL measurement, we propose that the PL peaks at 400 nm, 470 nm, 550 nm and 780 nm originate from ≡Ge−Si≡ center, ≡Si−Si≡ center, SPR center and GeO center, respectively.

Abstract: Dry and wet oxidation silica films doped with silicon ions were prepared using metal vapor vacuum arc (MEVVA) ion source implanter. The does of Si ion beams were kept constant at 3×1016 /cm2 and the energy varied from 42KeV to 70KeV. Five photoluminescence (PL) bands at the wavelength of 560nm, 580nm, 620nm, 650nm and 730nm have been observed at room temperature in all samples. The results of XRD showed none of Si nanocrystals were formed in the as-implanted silica films and originations of the PL bands were defects introduced by implantation. The 560nm PL band originated from oxygen surplus defect small peroxy radical (SPR), whereas the PL bands which ranges from the wavelength of 620nm to 730nm were attributed to non bridge oxygen hole center (NBOHC). Elevating implantation energy resulted in intensity increasing of 560nm PL band of dry oxidation samples but had inverse effects on wet oxidation samples. Influence mechanism of implantation energy on the defect photoluminescence was discussed in this article.