Effects of forming gas annealing on luminescence properties of erbium silicate thin films

Abstract

While hydrogen passivation has led to enhanced luminescence in many erbium doped materials, its effects on Er oxides/silicates compounds has rarely been demonstrated. Here we report effects of forming gas annealing on the luminescence properties in such Er compound materials. A broad band photoluminescence in the ultraviolet/visible range, likely arising from structural defects in the material, is significantly suppressed after forming gas annealing. Concurrently, the Er near-infrared luminescence intensity and its lifetime increase by about a factor of two and three, respectively. The samples are further characterized with Rutherford backscattering for composition information, optical absorption for optically excitable Er concentrations and extended x-ray absorption fine structures for Er local environments. We discuss the hydrogen passivation effects in the context of diffusion limited relaxation processes and suggest pathways to further improving near-infrared luminescence properties in Er compound materials.

Erbium emission in Er:Y2O3 decorated fractal arrays of silicon nanowires

“…Though a precise estimation of the length covered by Er:Y 2 O 3 cannot be given with high accuracy, we can assert that at a depth of about 1.5 µm from the top, the presence of Y 2 O 3 is reduced below 10% of its concentration on the NWs tips for all the tilt angles. Moreover, we can exclude the formation of Er silicate at the interface between Er:Y 2 O 3 and Si NWs due to the low substrate temperature of 300° C used during the deposition, as already demonstrated in literature 33 , 41 .…”

Boosting photoresposive ability of WO3–Bi2O3 nanocomposite rods via annealing-induced intrinsic precipitation of nanosized Bi particles

“…The average band gap energy of H250, H350, and H450 is approximately 2.0, 1.95, and 1.86 eV, respectively. The marked improved light-harvesting ability of the composite nanorods formed after high-temperature hydrogen gas-contained annealing may be attributed to the increased surface defects after the annealing process [38], and the surface thin Bi 2 O 3 layer reduction engendered formation of metallic Bi particles. Similarity, Lu et al, shows the surface oxygen vacancies possess a new donor level, which endow the Bi 2 O 3 /Bi 2 O 2 CO 3 semiconductor with the narrowed band gap energy to facilitate improved visible light harvesting [39].…”

Optical and structural investigations of annealing impact on phase separation of Erbium-doped Al2O3 layers

“…The first stage of CL intensity increases (up to 850 • C), dealing with homogeneous distribution of all elements, especially Er ions, in the Er:Al 2 O 3 layer. It can be associated with recovering of growth defects and densification of the film such as the O vacancy defects originally present in the sample that may have been removed by the annealing treatment [33]. Also, the increase of the Er-related luminescence can partially be explained by the formation of Er-O complexes that appear after annealing.…”