The Preparation Of SiO₂:Er Films By Ion Implantation Combined With Thermal Annealing And Its Microstructural And Optical Properties

The emission of Er3+ around 1.54μm in silicate host matrices drives great interest as this wavelength corresponds to the minimum attenuation in silica-based optical fibers (third window). High density ions implantation would cause much defect in silicate host matrix.In our study, erbium doped glass was prepared by ions implantation method with the density of 3×1016 cm-2. Annealing of the samples was performed in air in the temperature range between 500℃and 1000℃for 1 hour. They were characterized with Raman spectra, X-ray Photoelectron spectra (XPS), absorption spectra, and photoluminescence spectra (PL).From the Raman spectra, we concluded that SiO2 defect conformed while annealing. XPS measurements indicated that the formation of Si and SiO was observed through annealing at 900℃.In our experiment, visible and infrared luminescence has been obtained from SiO2:Er thin films. These spectra can be attributed to the transitions of 4F13/2→4F15/2, 4S3/2→4F15/2 and 2H11/2→4F15/2, and a broad defect-related emission was observed. At room temperature, the strongest PL intensity from Er3+ was observed for the sample annealed at 900℃.The PL signal of the SiO2:Er samples was obtained over the 80–300 K temperature range. The intensity of the 550 nm emission decreases with increasing temperature, while the intensity of the 525 nm line actually peaks at 300 K. This effect is explained based on the thermalization of electrons between the two closely spaced energy levels.A fortuitous temperature dependence of the 4S3/2 levels to the 4I15/2 ground state was discovered. The intensity of the 4S3/2 spectrum increases with increasing temperature below 180 K, then decreases from 180 K to room temperature, which can be attributed to energy transfer from Er3+ to SiO2 defect.