Papers by Keyword: Photo Luminescence

Abstract: A blue emitting phosphor BaAl₂O₄ doped with Gd³⁺ were prepared by combustion method at 500⁰C. The prepared phosphor were investigated by X-ray Diffraction to determine the crystalinity. Photoluminescence emission spectra centred at 369 nm under ultraviolet region, which corresponds to 5d-4f transition of Gd³⁺ ions. The PL spectra showed strong emission peak intensity and extending to 400nm to 453nm.Concentration quenching mechanism were occurred about 1mol% of Gd³⁺ ion. The results revealed that phosphor prepared by using combustion method can be useful WLED.

Abstract: In this work, zinc stannate (Zn₂SnO₄) nanomaterials were synthesized as a composite system of zinc oxide and tin oxide by sol-gel via hydrolysis process for 60 hours. The effect of annealing temperature on the structural, optical and electrical performances of zinc stannate nanomaterials has been studied. XRD studies revealed that zinc stannate possess spinel cubic crystal structure and their growth in the preferred orientation (311) with characteristic temperature. The surface morphology of the zinc stannate nanomaterials were obtained by scanning electron microscope (SEM). EDAX and FTIR studies were employed to determine the chemical compositions and functional groups of the zinc stannate respectively. The optical properties of the hydrolysed zinc stannate were analysed by UV-visible and photoluminescence spectroscopy. UV-vis spectra were associated to the optical bandgap with a tunable range of 3.17-3.92 eV. PL spectra exhibit the stable broad blue-green emission around 400-600 nm with various excitation wavelengths. Complex impedance spectra reveal that the resistivity of the prepared zinc stannate nanomaterials is in the order of ~ 10⁵ Ω Cm. Hence, zinc stannate is a promising candidate for DSSC applications.

Abstract: Metal contamination impact on transistors’ degradation has been widely studied. Nonetheless, most of the work has been performed on blanket wafers, or based on punctual yield crisis during the integrated circuits’ manufacturing. This paper proposes a comparison of the contamination and metals removal efficiency between blanket wafers and inside deep silicon trenches.