Journal of Vacuum Science & Technology A Vacuum Surfaces and Films (J VAC SCI TECHNOL A)

Publisher: American Vacuum Society; American Institute of Physics, American Vacuum Society

Journal description

The Journal of Vacuum Science and Technology A is devoted to reports of original research, review articles, and Critical Review articles. JVST A will include topics such as applied surface science, electronic materials and processing, fusion technology, plasma technology, surface science, thin films, vacuum metallurgy, and vacuum technology. It will contain the program and papers from the AVS National Symposium as well as the papers from other conferences and symposia sponsored by the AVS and its Divisions. JVST A is published six times annually.

Current impact factor: 2.32

Impact Factor Rankings

2016 Impact Factor Available summer 2017
2014 / 2015 Impact Factor 2.322
2013 Impact Factor 2.14
2012 Impact Factor 1.432
2011 Impact Factor 1.253
2010 Impact Factor 1.286
2009 Impact Factor 1.297
2008 Impact Factor 1.173
2007 Impact Factor 1.278
2006 Impact Factor 1.394
2005 Impact Factor 1.399
2004 Impact Factor 1.557
2003 Impact Factor 1.628
2002 Impact Factor 1.301
2001 Impact Factor 1.448
2000 Impact Factor 1.569
1999 Impact Factor 1.742
1998 Impact Factor 1.612
1997 Impact Factor 1.576
1996 Impact Factor 1.612
1995 Impact Factor 1.662
1994 Impact Factor 1.771
1993 Impact Factor 1.699
1992 Impact Factor 2.154

Impact factor over time

Impact factor
Year

Additional details

5-year impact 1.86
Cited half-life >10.0
Immediacy index 0.37
Eigenfactor 0.01
Article influence 0.52
Website Journal of Vacuum Science and Technology A website
Other titles Journal of vacuum science & technology. A. Vacuum, surfaces, and films, JVST A, Journal of vacuum science and technology., Vacuum, surfaces, and films
ISSN 0734-2101
OCLC 8697396
Material type Periodical, Internet resource
Document type Journal / Magazine / Newspaper, Internet Resource

Publisher details

American Vacuum Society

  • Pre-print
    • Author can archive a pre-print version
  • Post-print
    • Author can archive a post-print version
  • Conditions
    • On a public eprint server
    • On authors and employers website
    • Publisher's version/PDF may be used, on authors and employers website only
    • Must link to publisher abstract version
    • Published source must be acknowledged (see policy for wording)
    • If funding agency rules apply, authors may post articles in PubMed Central 12 months after publication
  • Classification
    green

Publications in this journal

  • [Show abstract] [Hide abstract]
    ABSTRACT: It is predicted that the quantum efficiency (QE) of photoelectron emission from metals may be enhanced, possibly by an order of magnitude, through optimized surface texture. Through extensive computational simulations, it is shown that the absorption enhancement in select surface groove geometries may be a dominant contributor to enhanced QE and corresponds to localized Fabry-Perot resonances. The inadequacy of extant analytical models in predicting the QE increase, and suggestions for further improvement, are discussed.
    No preview · Article · Mar 2016 · Journal of Vacuum Science & Technology A Vacuum Surfaces and Films
  • [Show abstract] [Hide abstract]
    ABSTRACT: The sensitivity of the surface morphology and microstructure of N-polar-oriented InAlN to variations in composition, temperature, and layer thickness for thin films grown by plasma-assisted molecular beam epitaxy(PAMBE) has been investigated. Lateral compositional inhomogeneity is present in N-rich InAlN films grown at low temperature, and phase segregation is exacerbated with increasing InN fraction. A smooth, step-flow surface morphology and elimination of compositional inhomogeneity can be achieved at a growth temperature 50 °C above the onset of In evaporation (650 °C). A GaN/AlN/GaN/200-nm InAlN heterostructure had a sheet charge density of 1.7 × 1013 cm−2 and no degradation in mobility (1760 cm2/V s) relative to 15-nm-thick InAlN layers. Demonstration of thick-barrier high-electron-mobility transistors with good direct-current characteristics shows that device quality, thick InAlN layers can be successfully grown by PAMBE.
    No preview · Article · Mar 2016 · Journal of Vacuum Science & Technology A Vacuum Surfaces and Films
  • [Show abstract] [Hide abstract]
    ABSTRACT: This study explored the internal oxidation of laminated Hf-Ru coatings by using cyclical gradient chemical concentration distribution along the growth direction. Hf-rich, near-equiatomic, and Ru-rich Hf-Ru coatings were prepared using direct-current magnetron cosputtering. Oxidation was examined by annealing the coatings at 500 and 600 °C in a 1% O2-99% Ar atmosphere for 30 min. The results indicated that internally oxidized laminated Hf-Ru coatings formed after annealing at 600 °C. Hf preferentially oxidized and formed monoclinic HfO2. The Ru-rich Hf0.11Ru0.89 coatings exhibited a higher oxidation resistance and superior mechanical properties.
    No preview · Article · Mar 2016 · Journal of Vacuum Science & Technology A Vacuum Surfaces and Films
  • [Show abstract] [Hide abstract]
    ABSTRACT: The authors present a viable process to grow the high quality graphene films with control over number of layers by the filtered cathodic vacuum arc (FCVA) technique. In the FCVA process, the different carbon concentrations can be controlled by precisely tuning the arc time (1-4 s). The arc generated carbon was deposited on the nickel catalyst at 800 °C, annealed for 10 min, and cooled down to room temperature in the presence of hydrogen gas, resulting in the graphene films with control over number of layers. Prior to arcing, hydrogen etching of nickel was carried out to clean the surface of the substrate. A growth model to prepare the high quality graphene has also been proposed. The as-grown graphene films were transferred to different substrates and are characterized by Raman spectroscopy, optical microscopy, high resolution transmission electron microscopy, and atomic force microscopy to determine the number of layers present in these films. Raman spectra of the prepared graphene films exhibit change in the G peak position from 1582.4 to 1578.1 cm-1, two-dimensional (2D) peak shifts from 2688.5 to 2703.8 cm-1, the value of I2D/IG increased from 0.38 to 3.82, and the full width at half maxima of 2D peak changed from 41 to 70 cm-1, for different layers of graphene films. The high resolution transmission electron microscopy image revealed that the graphene films prepared for 1 and 2 s arc times have single and bi- or trilayered structures, respectively.
    No preview · Article · Mar 2016 · Journal of Vacuum Science & Technology A Vacuum Surfaces and Films
  • [Show abstract] [Hide abstract]
    ABSTRACT: The growth conditions of tungsten thin films were investigated using various substrates including Si, Si/SiO2, GaAs, MgO, and Al2O3, and recipes were discovered for the optimal growth conditions of thick metastable β-phase tungsten films on Si, GaAs, and Al2O3 substrates, which is an important material in spin orbit torque studies. For the Si/SiO2 substrate, the crystal phase of the tungsten films was different depending upon the tungsten film thickness, and the transport properties were found to dramatically change with the thickness owing to a change in phase from the α + β phase to the α-phase. It is shown that the crystal phase changes are associated with residual stress in the tungsten films and that the resistivity is closely related to the grain sizes.
    No preview · Article · Mar 2016 · Journal of Vacuum Science & Technology A Vacuum Surfaces and Films
  • [Show abstract] [Hide abstract]
    ABSTRACT: In this study, the authors propose a new in situ degassing method by which only kicker magnets in the accelerator beam line are baked out without raising the temperature of the vacuum chamber to prevent unwanted thermal expansion of the chamber. By simply installing the heater and thermal radiation shield plates between the kicker magnet and the chamber wall, most of the heat flux from the heater directs toward the kicker magnet. The result of the verification test showed that each part of the kicker magnet was heated to above the target temperature with a small rise in the vacuum chamber temperature. A graphiteheater was selected in this application to bake-out the kicker magnet in the beam line to ensure reliability and easy maintainability of the heater. The vacuum characteristics of graphite were suitable for heater operation in the beam line. A preliminary heat-up test conducted in the accelerator beam line also showed that each part of the kicker magnet was successfully heated and that thermal expansion of the chamber was negligibly small.
    No preview · Article · Mar 2016 · Journal of Vacuum Science & Technology A Vacuum Surfaces and Films
  • [Show abstract] [Hide abstract]
    ABSTRACT: Thin ZnO:Al layers were deposited by pulsed laser deposition in vacuum and in oxygen atmosphere at gas pressures between 10 and 70 Pa and by applying radio-frequency (RF) plasma. Grazing incidence small angle x-ray scattering and grazing incidence x-ray diffraction (GIXRD) data showed that an increase in the oxygen pressure leads to an increase in the roughness, a decrease in the sample density, and changes in the size distribution of nanovoids. The nanocrystal sizes estimated from GIXRD were around 20 nm, while the sizes of the nanovoids increased from 1 to 2 nm with the oxygen pressure. The RF plasma mainly influenced the nanostructural properties and point defects dynamics. The photoluminescence consisted of three contributions, ultraviolet (UV), blue emission due to Zn vacancies, and red emission, which are related to an excess of oxygen. The RF excitation lowered the defect level related to blue emission and narrowed the UV luminescence peak, which indicates an improvement of the structural ordering. The observed influence of the deposition conditions on the film properties is discussed as a consequence of two main effects: the variation of the energy transfer from the laser plume to the growing film and changes in the growth chemistry.
    No preview · Article · Mar 2016 · Journal of Vacuum Science & Technology A Vacuum Surfaces and Films
  • [Show abstract] [Hide abstract]
    ABSTRACT: The growing interest in metal oxide based semiconductor technologies has driven the need to produce high quality epitaxialfilms of one metal oxide upon another. Largely unrecognized in synthetic efforts is that some metal oxides offer strongly polar surfaces and interfaces that require electrostatic stabilization to avoid a physically implausible divergence in the potential. The present work examines these issues for epitaxialgrowth of anatase TiO2 on strontium titanate (001). Solid phase epitaxial regrowth yields only the (001) facet, while direct crystalline growth by atomic layer deposition yields both the (112) and (001). The presence of amorphous TiO2 during regrowth may provide preferential stabilization for formation of the (001) facet.
    No preview · Article · Mar 2016 · Journal of Vacuum Science & Technology A Vacuum Surfaces and Films
  • [Show abstract] [Hide abstract]
    ABSTRACT: Ion dynamics are investigated in a dual frequency radio frequency sheath as a function of radius above a 30 cm diameter biased silicon wafer in an industrial inductively coupled (440 kHz, 500 W) plasmaetch tool. Ion velocity distribution (IVD) function measurements in the argon plasma are taken using laser induced fluorescence. Planar sheets of laser light enter the chamber both parallel and perpendicular to the surface of the wafer in order to measure both parallel and perpendicular IVDs at thousands of spatial positions. A fast (30 ns exposure) charge coupled device camera measures the resulting fluorescence with a spatial resolution of 0.4 mm. The dual-frequency bias on the wafer is comprised of a 2 MHz low frequency (LF) bias and a 19 MHz high frequency bias. The laser is phase locked to the LF bias and IVD measurements are taken at several different LF phases. Ion energy distribution (IED) function measurements and calculated moments are compared for several cases. IEDs were measured at two disparate phases of the phase-locked LF bias. IEDs were found to be multipeaked and were well-approximated by a sum of Maxwellian distributions. The calculated fluxes in the dual frequency case were found to be substantially more radially uniform than the single frequency bias case. For industrial applications, this radially uniform ion flux is evidently a trade off with the undesirable multipeaked structure in the IEDs.
    No preview · Article · Mar 2016 · Journal of Vacuum Science & Technology A Vacuum Surfaces and Films
  • [Show abstract] [Hide abstract]
    ABSTRACT: In this work, a transmission-type, low-kilovolt coherent electron diffractive imaging instrument was constructed. It comprised a single-atom field emitter, a triple-element electrostatic lens, a sample holder, and a retractable delay line detector to record the diffraction patterns at different positions behind the sample. It was designed to image materials thinner than 3 nm. The authors analyzed the asymmetric triple-element electrostatic lens for focusing the electron beams and achieved a focused beam spot of 87 nm on the sample plane at the electron energy of 2 kV. High-angle coherent diffraction patterns of a suspended graphene sample corresponding to (0.62 Å)-1 were recorded. This work demonstrated the potential of coherent diffractive imaging of thin two-dimensional materials, biological molecules, and nano-objects at a voltage between 1 and 10 kV. The ultimate goal of this instrument is to achieve atomic resolution of these materials with high contrast and little radiation damage.
    No preview · Article · Mar 2016 · Journal of Vacuum Science & Technology A Vacuum Surfaces and Films
  • [Show abstract] [Hide abstract]
    ABSTRACT: The current technology used in linear particle accelerators is based on superconducting radio frequency (SRF) cavities fabricated from bulk niobium(Nb), which have smaller surface resistance and therefore dissipate less energy than traditional nonsuperconducting copper cavities. Using bulk Nb for the cavities has several advantages, which are discussed elsewhere; however, such SRF cavities have a material-dependent accelerating gradient limit. In order to overcome this fundamental limit, a multilayered coating has been proposed using layers of insulating and superconducting material applied to the interior surface of the cavity. The key to this multilayered model is to use superconducting thin films to exploit the potential field enhancement when these films are thinner than their London penetration depth. Such field enhancement has been demonstrated in MgB2thin films; here, the authors consider films of another type-II superconductor, niobium nitride (NbN). The authors present their work correlating stoichiometry and superconducting properties in NbN thin films and discuss the thickness dependence of their superconducting properties, which is important for their potential use in the proposed multilayer structure. While there are some previous studies on the relationship between stoichiometry and critical temperature TC, the authors are the first to report on the correlation between stoichiometry and the lower critical field HC1.
    No preview · Article · Mar 2016 · Journal of Vacuum Science & Technology A Vacuum Surfaces and Films
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The alkali species Cs and K were codeposited using an effusion source, onto relatively thick layers of Sb (50 nm to ∼7 μm) grown on GaAs and Ta substrates inside a vacuum chamber that was baked and not-vented, and also baked and vented with clean dry nitrogen but not rebaked. The characteristics of the Sb films, including sticking probability, surface roughness, grain size, and crystal properties were very different for these conditions, yet comparable values of photocathode yield [or quantum efficiency (QE)] at 284 V were obtained following codeposition of the alkali materials. Photocathodes manufactured with comparatively thick Sb layers exhibited the highest QE and the best 1/e lifetime. The authors speculate that the alkali codeposition enabled optimized stoichiometry for photocathodes manufactured using thick Sb layers, which could serve as a reservoir for the alkali materials.
    Preview · Article · Mar 2016 · Journal of Vacuum Science & Technology A Vacuum Surfaces and Films
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Outgassing rates of three low-carbon steels were measured using rate-of-rise and throughput methods. Outgassing rates of water vapor during pump-down were higher than those of stainless steels, probably due to the nature of native surface oxide layer. However, hydrogen outgassing rates without a high temperature pretreatment were as low as (1-4) × 10-10Pa m3 s-1 m-2, which is much lower than that of untreated stainless steels. No dramatic reduction was observed in H2 outgassing after vacuum annealing at 850 °C for 12 h, suggesting that the low-carbon steels had been fully degassed during the steelmaking processes. This may be due to the use of the Ruhrstahl-Hausen vacuum process during steel refining instead of an older process, such as argon-oxygen decarburization. The extremely low H2 outgassing rate from low-carbon steels makes them applicable for use in ultrahigh vacuum or even extreme high vacuum applications, particularly where magnetic field shielding is needed.
    Full-text · Article · Mar 2016 · Journal of Vacuum Science & Technology A Vacuum Surfaces and Films

  • No preview · Article · Mar 2016 · Journal of Vacuum Science & Technology A Vacuum Surfaces and Films