Articles you may be interested inA thermalization energy analysis of the threshold voltage shift in amorphous indium gallium zinc oxide thin film transistors under simultaneous negative gate bias and illumination Amorphous gallium indium zinc oxide ͑a-GIZO͒ thin films of different compositions ͑Ga 2 O 3 :In 2 O 3 :ZnO=1:1:1,2:2:1,3:2:1,4:2:1͒ on Si substrates were investigated by high-resolution x-ray photoelectron spectroscopy and x-ray absorption spectroscopy ͑XAS͒ using synchrotron radiation. The O 1s, Ga 3d, In 4d, Zn 3d core, and shallow-core levels as well as the valence band maxima and O K-edge XAS were investigated. Each O 1s spectrum could be deconvoluted by a main component ͑O 1 in the text͒ representing the Ga-In-Zn-O quaternary system along with two other higher-binding energy ͑BE͒ components ͑O 2 and O 3 in the text͒. The O 2 +O 3 intensity increased as the Ga 2 O 3 content increased. For the as-prepared samples, the spectral peak separations between the Ga 3d ͑ϳ20 eV͒ and Zn 3d ͑ϳ11 eV͒ orbitals and between the In 4d ͑ϳ18 eV͒ and Zn 3d orbitals became larger, respectively, as the Ga 2 O 3 content increased. For the surface-cleaned samples, this trend was the same but with smaller increases in their separations. The sputter-cleaning effectively reduced the Zn 3d intensity by ϳ30% relative to those of Ga 3d and In 4d. The valence band maximum shifted toward higher BE, up to ϳ0.5 eV for the as-prepared samples and ϳ0.25 eV for the cleaned samples, and the conduction band minimum ͑measured at the O K-edge͒ was measured at photon energies ranging upwards to ϳ0.2 eV as the Ga 2 O 3 content increased, demonstrating that the band gap can be tailored by increasing the Ga 2 O 3 content. The effects of increasing Ga 2 O 3 contents on the local chemical states and the corresponding electrical conduction are discussed in this paper.

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Amorphous In-Ga-Zn-O (a-IGZO) thin-film surfaces were air annealed at 150°C, 300°C, and 400°C for 10 minutes, after which the X-ray photoelectron spectroscopic (XPS) spectral changes were investigated. The data show that air annealing decreased the densities of the oxygen-vacancy-representing states and generated the contaminant component at the O 1s peak. The contaminant component's intensity there decreased as the annealing temperature was increased above 300°C. As the annealing temperature was increased to 400°C, the intensities of O 1s and Zn 3d relative to that of Ga 3d increased by ∼100% and ∼130%, respectively, whereas the intensity of In 3d, relative to that of Ga 3d, decreased by ∼30%.

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Nitrogen doped SnO 2 thin films (thickness ~ 250 nm) were deposited at different substrate temperature by radio frequency (rf) sputtering method. Crystal structure,morphology and optical properties of these films were investigated by x-ray diffraction (XRD), atomic force microscopy (AFM) and UV-VIS-NIR spectrophotometer, respectively. XRD measurement suggests that the film deposited at room temperature was amorphous in nature and films deposited at higher temperature were crystalline in nature. The film deposited at RT and 200 o C have transparency more than 90% in visible region but the film deposited at 400 o C has lesser transparency.Red shift was observed in the absorption edge may be due to decrease in ionicity due tothe formation of the Sn-N bond.