Resistivity measurement of an a-axis-oriented YBa2Cu3O7–δ thin film at 450-650 °C

Resistivity measurement of an a-axis-oriented YBa2Cu3O7-δ (YBCO) thin film was carried out in a stream of O2/Ar mixtures at 450–650 °C. Rapidly reversible change in the resistivity of the YBCO film was observed as a function of the oxygen partial pressure in the ambient atmosphere due to the oxygen in-/out-diffusion in the YBCO film. Resistivity measurement of YBCO thin films at higher temperatures of 450–650 °C was found to be quite effective to predict the influence of fabricating processes on the superconducting properties of YBCO films.

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Pulsed Laser Deposited Oxide Green Emitting Thin Film Phosphors : Optimization of Growth Conditions

MRS Proceedings ◽

10.1557/proc-988-0988-qq06-12 ◽

2006 ◽

Vol 988 ◽

Author(s):

P. Thiyagarajan ◽

M. Kottaismay ◽

M S Ramachandra Rao

Keyword(s):

Thin Film ◽

Thin Films ◽

Oxygen Partial Pressure ◽

Partial Pressure ◽

Diffuse Reflectance Spectroscopy ◽

Quartz Substrate ◽

Pulsed Laser ◽

Growth Conditions ◽

Ex Situ ◽

Morphological Studies

AbstractStructural and photoluminescence (PL) properties of Zn2(1-x)MnxSiO4 (1 ≤ x ≤ 5) and diffuse reflectance spectroscopy (DRS) and morphological studies of ZnGa2O4:Mn thin film green emitting phosphors grown using pulsed laser deposition (PLD) technique have been investigated. Zn2(1-x)MnxSiO4 thin films grown on Si substrate at 700°C in 300 mTorr of oxygen partial pressure, upon ex-situ annealing at higher temperatures exhibit superior PL intensity. ZnGa2O4:Mn phosphor thin films grown on quartz substrate at 650oC and in-situ annealed in 300mTorr of oxygen partial pressure show better emission intensity. For both Zn2SiO4:Mn and ZnGa2O4:Mn phosphors, luminescence can be assigned to 4T1 – 6A1 transition of Mn2+ within the 3d orbital giving rise to emission at 525 and 503 nm, respectively.

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Structural and Ferroelectric Properties of Large c/a Phase Bismuth Ferrite Thin Films Prepared by Ion Beam Sputtering

MRS Proceedings ◽

10.1557/opl.2011.17 ◽

2011 ◽

Vol 1292 ◽

Author(s):

Seiji Nakashima ◽

Yosuke Tsujita ◽

Hironori Fujisawa ◽

Jung Min Park ◽

Takeshi Kanashima ◽

...

Keyword(s):

Thin Film ◽

Thin Films ◽

Oxygen Partial Pressure ◽

Partial Pressure ◽

Domain Switching ◽

Ion Beam ◽

Ferroelectric Properties ◽

Mixed Phase ◽

Ion Beam Sputtering ◽

Beam Sputtering

ABSTRACTBiFeO3 (BFO) thin films have been deposited on SrRuO3/SrTiO3 (001) substrate by using ion beam sputtering process. At low oxygen partial pressure of 11 m Pa, rhombohedral and large c/a mixed phase thin film have been obtained in spite of rhombohedral BFO single phase formation at high oxygen partial pressure of 73 mPa. From wide area 2θ-Ψ mappings, diffraction peaks from large c/a phase BFO thin film were obtained with the same extinction rule as those of rhombohedral BFO. Reciprocal space mappings around BFO (003) and BFO (103) spots indicate that lattice parameters of large c/a phase BFO were a = 0.381 nm and c = 0.461 nm (c/a =1.22), respectively. Moreover ferroelectric domain switching could be observed in both of rhombohedral BFO and mixed phase BFO thin films.

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Improvement in the Electrical Performance of Ge-Doped InZnO Thin-Film Transistor

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2015.11156 ◽

2015 ◽

Vol 15 (10) ◽

pp. 7537-7541 ◽

Cited By ~ 8

Author(s):

Yong Jin Im ◽

Sang Jo Kim ◽

Ji Hun Shin ◽

Seung Soo Ha ◽

Chan Hee Park ◽

...

Keyword(s):

Thin Film ◽

Thin Films ◽

Oxygen Partial Pressure ◽

Partial Pressure ◽

Thin Film Transistor ◽

Processing Parameters ◽

Binding Energies ◽

Oxide Semiconductor ◽

Electrical Performance ◽

Sputtering Power

We fabricated amorphous oxide semiconductor thin-film transistors (TFTs) using Ge-doped InZnO (Ge–IZO) thin films as active-channel layers. The Ge–IZO thin films were deposited at room temperature by radio-frequency (RF) magnetron co-sputtering system, and then annealed in air for 1 h at 300 °C. Some processing parameters such as sputtering oxygen partial pressure [O2/(Ar + O2)] and sputtering power for GeO2 target were changed to investigate what was the optimal amount of Ge in the Ge–IZO active layer. A small concentration of Ge added to IZO by co-sputtering enhanced the carrier concentration, mobility, and conductivity; but further increase in Ge concentration degraded the device performance. In order to optimize the electrical properties of Ge–IZO TFTs, we tried to adjust the processing parameters and the best Ge–IZO TFT was obtained at a co-sputtering oxygen partial pressure of 2% and GeO2 target power of 10 W. The fabricated Ge–IZO TFT exhibited an on/off ratio of 3.0×107, a saturation mobility of 13.05 cm2/V · s, a subthreshold swing of 0.95 V/dec, and a threshold voltage of 0 V. XPS and XRD analyses of Ge–IZO films were performed to investigate the binding energies of atoms in Ge–IZO films and the crystallinity of the films. 90% transmittance of visible light was achieved, which makes the technology useful for transparent devices.

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