Thin Films of Y-Ba-Cu-O by Rf Sputtering

1987 ◽  
Vol 99 ◽  
Author(s):  
Paul H. Ballentine ◽  
A. M. Kadin ◽  
J. Árgana ◽  
R. C. Rath
Keyword(s):  
Thin Films ◽  
Substrate Temperature ◽  
Critical Current ◽  
Mixed Oxide ◽  
Room Temperature ◽  
Rf Sputtering ◽  
Cu Content ◽  
Powder Target ◽  
Single Target ◽  
Zero Resistance

ABSTRACTThin films of Y-Ba-Cu-O have been prepared by rf diode sputtering from a single mixed-oxide powder target. The films were deposited on sapphire and cubic zirconia substrates, with the substrates either cooled, heated, or left to establish thermal equlibrium. The Cu content in the films decreased with increasing substrate temperature. Films having composition close to the desired 1–2–3 stoichiometry were fabricated either by enriching the target with CuO or by cooling the substrate. Using the latter approach, a single target was used for over 20 depositions yielding films that were uniform in composition (although slightly Cu-rich), and consistent from run to run. These films had as-deposited room temperature sheet resistances on the order of 100 kΩ. Subsequent annealing at temperatures up to 850 C resulted in films that were superconducting with an onset around 90 K and zero resistance at 50 K. The critical current was found to exceed 2000 A/cm2 at 4.2 K.

Investigation of ultra-thin films of YBa2Cu3O7−δ grown on MgO

1990 ◽  
Vol 48 (4) ◽  
pp. 6-7
Author(s):  
S.K. Streiffer ◽  
C.B. Eom ◽  
J.C. Bravman ◽  
T.H. Geballet
Keyword(s):  
Thin Films ◽  
Room Temperature ◽  
Deposition Process ◽  
Nucleation And Growth ◽  
Multilayer Structures ◽  
Rf Power ◽  
Oxygen Loss ◽  
Transmission Electron ◽  
Single Target ◽  
Mtorr Argon

The study of very thin (<15 nm) YBa2Cu3O7−δ (YBCO) films is necessary both for investigating the nucleation and growth of films of this material and for achieving a better understanding of multilayer structures incorporating such thin YBCO regions. We have used transmission electron microscopy to examine ultra-thin films grown on MgO substrates by single-target, off-axis magnetron sputtering; details of the deposition process have been reported elsewhere. Briefly, polished MgO substrates were attached to a block placed at 90° to the sputtering target and heated to 650 °C. The sputtering was performed in 10 mtorr oxygen and 40 mtorr argon with an rf power of 125 watts. After deposition, the chamber was vented to 500 torr oxygen and allowed to cool to room temperature. Because of YBCO’s susceptibility to environmental degradation and oxygen loss, the technique of Xi, et al. was followed and a protective overlayer of amorphous YBCO was deposited on the just-grown films.

Characteristics of CIGS thin films prepared by RF sputtering employing CIGS single target

2011 ◽  
Author(s):  
Tae-Won Kim ◽  
Young-Baek Kim ◽  
Sang-In Song ◽  
Chae-Whan Jung ◽  
Jong-Ho Lee
Keyword(s):  
Thin Films ◽  
Rf Sputtering ◽  
Single Target

Characterization of Epitaxial Superconducting YBacuO Thin Films with Three Different Orientations

1989 ◽  
Vol 169 ◽  
Author(s):  
X.K. Wang ◽  
D.X. Li ◽  
S.N. Song ◽  
J.Q. Zheng ◽  
R.P.H. Chang ◽  
...  
Keyword(s):  
Thin Films ◽  
Critical Current Density ◽  
Critical Current ◽  
Current Density ◽  
Orientation Dependence ◽  
Zero Field ◽  
Epitaxial Thin Films ◽  
Oriented Film ◽  
Zero Resistance ◽  
Xrd Patterns

AbstractEpitaxial thin films of YBaCuO were prepared by multilayer deposition from Y, Cu, and BaF2 sources with: (1) the a‐axis perpendicular to (100)SrTiO3; (2) the c‐axis perpendicular to (100)SrTiO3; and (3) the [110] axis perpendicular to (110)SrTiO3. XRD patterns as well as SEM and HREM images confirm that the films are highly oriented, essentially epitaxial. Both the a‐axis oriented and the c‐axis oriented films exhibit zero resistance at 91K. The [110] oriented film shows the sharpest transiton with a transition width of IK and zero resistance at 85K. The zero field critical current density, Jc, determined magnetically, is in excess of 107A/cm2 at 4.4K and 1.04 x 106A/cm2 at 77K for the c‐axis oriented film; for the a‐axis oriented film we obtained 6.7 x 106A/cm2 at 4.4K and 1.2 x 105A/cm2 at 77K. The orientation dependence of the critical current density in the basal plane of the a‐axis oriented film was studied. The largest Jc's occur along the in‐plane <100> axes of the substrate.

AFM Study of Surface Morphology of Aluminum Nitride Thin Films

1995 ◽  
Vol 388 ◽  
Author(s):  
Yoshihisa Watanabe ◽  
Yoshikazu Nakamura ◽  
Shigekazu Hirayama ◽  
Yuusaku Naota
Keyword(s):  
Thin Films ◽  
Surface Morphology ◽  
Substrate Temperature ◽  
Single Crystal ◽  
Room Temperature ◽  
Ion Beam ◽  
Soda Lime ◽  
Silicon Single Crystal ◽  
Soda Lime Glass ◽  
Average Roughness

AbstractAluminum nitride (AlN) thin films have been synthesized by ion-beam assisted deposition method. Film deposition has been performed on the substrates of silicon single crystal, soda-lime glass and alumin A. the influence of the substrate roughness on the film roughness is studied. the substrate temperature has been kept at room temperature and 473K and the kinetic energy of the incident nitrogen ion beam and the deposition rate have been fixed to 0.5 keV and 0.07 nm/s, respectively. the microstructure of the synthesized films has been examined by X-ray diffraction (XRD) and the surface morphology has been observed by atomic force microscopy(AFM). IN the XRD patterns of films synthesized at both room temperature and 473K, the diffraction line indicating the alN (10*0) can be discerned and the broad peak composed of two lines indicating the a1N (00*2) and a1N (10*1) planes is also observed. aFM observations for 100 nm films reveal that (1) the surface of the films synthesized on the silicon single crystal and soda-lime glass substrates is uniform and smooth on the nanometer scale, (2) the average roughness of the films synthesized on the alumina substrate is similar to that of the substrate, suggesting the evaluation of the average roughness of the film itself is difficult in the case of the rough substrate, and (3) the average roughness increases with increasing the substrate temperature.

Substrate temperature effects on the growth and properties of γ-MnS thin films grown by rf sputtering

2002 ◽  
Vol 37 (10) ◽  
pp. 1749-1754 ◽  
Author(s):  
I Oidor-Juárez ◽  
P Garcı́a-Jiménez ◽  
G Torres-Delgado ◽  
R Castanedo-Pérez ◽  
O Jiménez-Sandoval ◽  
...  
Keyword(s):  
Thin Films ◽  
Substrate Temperature ◽  
Temperature Effects ◽  
Rf Sputtering

IN-SITU PREPARATION OF YBa2Cu3O7 SUPERCONDUCTING THIN FILMS BY PULSED Nd:YAG LASER DEPOSITION

1992 ◽  
Vol 06 (08) ◽  
pp. 477-483 ◽  
Author(s):  
QINGXIN SU ◽  
SHIFA XU ◽  
DAFU CUI ◽  
HUIBIN LU ◽  
YONGJUN TIAN ◽  
...  
Keyword(s):  
Thin Films ◽  
Substrate Temperature ◽  
Nd:Yag Laser ◽  
Ac Susceptibility ◽  
Substrate Surface ◽  
Zero Magnetic Field ◽  
Superconducting Thin Films ◽  
In Situ Preparation ◽  
Zero Resistance

High-T c superconducting thin films of YBa 2 Cu 3 O 7 were grown in-situ on (100) SrTiO 3 substrates by Nedymium:yttrium aluminum garnet [Nd:YAG] laser ablation. The effects of the substrate temperature on the transition temperature, microcrystalline structure and surface morphology of the films were discussed. Best results were obtained in the 730°–770°C range. X-ray diffraction analysis showed that these films were highly c-oriented with the c-axis perpendicular to the substrate surface. At the optimum substrate temperature, a very smooth morphology with only a few small particles were observed by scanning electron microscopy. The zero resistance temperature of these films were ≥ 90 K with a narrow transition width and the ac susceptibility measurement also gave the same result. The highest critical current density obtained at 77 K and zero magnetic field was 3.8 × 106 A/cm 2.

Optical Properties of NiO Thin Films: A Potential Material for Optoelectronic Devices

2012 ◽  
Vol 488-489 ◽  
pp. 103-108 ◽  
Author(s):  
Manisha Tyagi ◽  
Monika Tomar ◽  
Vinay Gupta
Keyword(s):  
Thin Films ◽  
Refractive Index ◽  
Optical Properties ◽  
Substrate Temperature ◽  
Band Gap ◽  
Urbach Energy ◽  
Rf Sputtering ◽  
Blue Shift ◽  
Structural Disorder ◽  
Near Ir

The influence of substrate temperature on the UV-Visible-near-IR optical properties, namely the band gap, the Urbach energy and the refractive index of NiO thin films deposited by RF sputtering has been investigated. The optical band gap of thin films showed the blue-shift in the transmission spectra with increase in the substrate temperature which is related to variation in carrier concentration of the deposited films. Urbach energy (EU) values indicate that the films deposited at 400 oC substrate temperature show least structural disorder. The refractive index of the films is found to decrease continuously with increase in the substrate temperature at all photon energies in the visible and near-IR region, and is attributed to the decreasing packing density of the films. Introduction

scholarly journals Effects of the Argon Pressure on the Optical Band Gap of Zinc Oxide Thin Films Grown by Nonreactive RF Sputtering

2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
M. Acosta ◽  
I. Riech ◽  
E. Martín-Tovar
Keyword(s):  
Thin Films ◽  
Zinc Oxide ◽  
Band Gap ◽  
Room Temperature ◽  
Optical Band Gap ◽  
Rf Sputtering ◽  
Argon Pressure ◽  
Band Gaps ◽  
Zno Thin Films ◽  
Optical Band Gaps

Zinc oxide (ZnO) thin films were grown by nonreactive RF sputtering at room temperature under varying argon pressures (PAr). Their optical band gap was found to increase from 3.58 to 4.34 eV when the argon pressure increases from 2.67 to 10.66 Pa. After annealing at 200°C and 500°C, optical band gaps decrease considerably. The observed widening of the band gap with increasingPArcan be understood as being a consequence of the poorer crystallinity of films grown at higher pressures. Measurements of morphological and electrical properties of these films correlate well with this picture. Our main aim is to understand the effects ofPAron several physical properties of the films, and most importantly on its optical band gap.

Sign in / Sign up

Export Citation Format

Share Document