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1.
H.S. Nagaraja F. Ohnesorge D.K. Avasthi R. Neumann P. Mohan Rao 《Applied Physics A: Materials Science & Processing》2000,71(3):337-341
Single crystals of the amino acid benzoyl glycine (hippuric acid) are irradiated normal to the as-grown surface by highly
charged Bi ions with a kinetic energy of 2.38 GeV and a fluence of 1×1010 ions/cm2. The projectiles create circular craters with a mean diameter of 40 (10) nm on the surface of the crystal as observed by
scanning force microscopy (SFM). The mean depth amounts to 4 (1) nm, this value being considered as a lower limit due to the
finite radius of curvature of the force cantilever tip. Thus, on the average, each single-ion projectile seems to eject about
104 molecules. On the surface of non-irradiated crystals, SFM reveals terraces of a few monolayers in height. In water, it was
possible to visualize the lattice periodicity. Terraces were also observed on the irradiated crystal surface in the presence
of the craters, indicating that the crystal is still intact at the given dose.
Received: 25 May 2000 / Accepted: 26 May 2000 / Published online: 13 July 2000 相似文献
2.
F. Machalett K. Edinger J. Melngailis M. Diegel K. Steenbeck E. Steinbeiss 《Applied Physics A: Materials Science & Processing》2000,71(3):331-335
For direct writing of electrically conducting connections and areas into insulating gold oxide thin films a scanning Ar+ laser beam and a 30 keV Ga+ focused ion beam (FIB) have been used. The gold oxide films are prepared by magnetron sputtering under argon/oxygen plasma.
The patterning of larger areas (dimension 10–100 μm) has been carried out with the laser beam by local heating of the selected
area above the decomposition temperature of AuOx (130–150 °C). For smaller dimensions (100 nm to 10 μm) the FIB irradiation could be used. With both complementary methods
a reduction of the sheet resistance by 6–7 orders of magnitude has been achieved in the irradiated regions (e.g. with FIB
irradiation from 1.5×107 Ω/□ to approximately 6 Ω/□). The energy-dispersive X-ray analysis (EDX) show a considerably reduced oxygen content in the
irradiated areas, and scanning electron microscopy (SEM), as well as atomic force microscopy (AFM) investigations, indicate
that the FIB patterning in the low-dose region (1014 Ga+/cm2) is combined with a volume reduction, which is caused by oxygen escape rather than by sputtering.
Received: 30 May 2000 / Accepted: 31 May 2000 / Published online: 13 July 2000 相似文献
3.
T.V. Kononenko S.V. Garnov S.M. Pimenov V.I. Konov V. Romano B. Borsos H.P. Weber 《Applied Physics A: Materials Science & Processing》2000,71(6):627-631
Laser ablation of thin TiN films deposited on steel substrates has been studied under wide-range variation of irradiation
conditions (pulsewidth, wavelength, energy density and spot size). It has been demonstrated that both picosecond (150–300 ps)
and nanosecond (5–9 ns) laser pulses were suitable for controllable ablation and microstructuring of a 1-μm-thick TiN film
unlike longer 150-ns pulses. The ablation rate was found to be practically independent of the wavelength (270–1078 nm) and
pulsewidth (150 ps–9 ns), but it increased substantially when the size of a laser spot was reduced from 15–60 μm to 3 μm.
The laser ablation technique was applied to produce microstructures in the thin TiN films consisting of microcraters with
a typical size of 3–5 μm in diameter and depth less than 1 μm. Tests of lubricated sliding of the laser-structured TiN films
against a steel ball showed that the durability of lubricated sliding increased by 25% as compared to that of the original
TiN film.
Received: 28 July 1999 / Accepted: 17 April 2000 / Published online: 20 September 2000 相似文献
4.
Z.M. Chen Y.Q. Wu D.H. Gu F.X. Gan 《Applied Physics A: Materials Science & Processing》2007,88(2):409-414
Thin films of four nickel(II) and copper(II) hydrazone complexes, which will hopefully be used as recording layers for the
next-generation of high-density recordable disks, were prepared by using the spin-coating method. Absorption spectra of the
thin films on K9 optical glass substrates in the 300–700 nm wavelength region were measured. Optical constants (complex refractive
indices N) and thickness d of the thin films prepared on single-crystal silicon substrates in the 275–675 nm wavelength region
were investigated on a rotating analyzer-polarizer scanning ellipsometer by fitting the measured ellipsometric angles (Ψ(λ)
and Δ(λ)) with a 3-layer model (Si/dye film/air). The dielectric functions ε and absorption coefficients α as a function of
the wavelength were then calculated. Additionally, a design to achieve high reflectivity and optimum dye film thickness with
an appropriate reflective layer was performed with the Film Wizard software using a multilayered model (PC substrate/reflective
layer/dye film/air) at 405 nm wavelength.
PACS 81.05.L; 78.20.Ci; 78.20.-e 相似文献
5.
X. Zhu S. Lu H.L.W. Chan C.L. Choy K.H. Wong 《Applied Physics A: Materials Science & Processing》2003,76(2):225-229
Compositionally graded (Ba1-xSrx)TiO3 (BST) (x:0.0∼0.25) thin films were grown on Pt (111)/TiO2/SiO2/Si (100) substrates using layer-by-layer pulsed laser deposition in the temperature range 550–650 °C. Both downgraded (Ba/Sr
ratio varying from 100/0 at the bottom surface to 75/25 at the top surface) and upgraded (Ba/Sr ratio varying from 75/25 at
the bottom surface to 100/0 at the top surface) BST films were prepared. Their microstructures were systematically studied
by X-ray diffractometry and scanning electron microscopy. A grain morphology transition from large ‘rosettes’ (>0.30 μm) to
small compact grains (70–110 nm) was observed in the downgraded BST films as the deposition temperature was increased from
550 to 650 °C. No such grain morphology transition was detected in the upgraded BST films. Dielectric measurements with metal
electrodes revealed an enhanced dielectric behavior in the downgraded films. This enhancement is mainly attributed to the
large compressive stress field built up near the interface between the downgraded film and substrate. Furthermore, the BaTiO3 layer in the downgraded BST films not only serves as a bottom layer but also as an excellent seeding layer for enhancing
the crystallization of the subsequent film layers in the downgraded films.
Received: 10 December 2001 / Accepted: 12 March 2002 / Published online: 19 July 2002
RID="*"
ID="*"Corresponding author. Fax: 86-25/359-5535, E-mail: xhzhu@public1.ptt.js.cn 相似文献
6.
FT-IR spectroscopy and SFM were used to investigate the growth of thin films of the organic semiconductor 3,4,9,10-perylenetetracarboxylicdianhydride (PTCDA) deposited by vacuum sublimation onto various substrates, i.e. Ag(111) layers on mica, KBr(100), mica, oxidized Si, and TiO2 nanoparticles on Si. Layer thicknesses of PTCDA varied from 10 to 1500 nm.The anhydride vibrations of PTCDA differ for the used substrates, which can be connected to the orientation of the molecules relative to the substrate surface and the film morphology as detected in the SFM pictures. 相似文献
7.
S. A. Gavrilov V. V. Gusev V. S. Dneprovskii E. A. Zhukov A. N. Syrnikov I. V. Yaminskii E. A. Muljarov 《JETP Letters》1999,70(3):216-221
The characteristic features of the luminescence spectra of CdS semiconductor nanocrystals, crystallized in hollow channels
in a dielectric template, are explained in terms of excitonic transitions in semiconductor-insulator quantum wires. The excitonic
transition energies agree with the values calculated taking into account the effects of size quantization and the “dielectric
enhancement of excitons” — the large increase in the electron-hole attraction as a result of the difference between the permittivities
of the semiconductor and insulator. The theoretically computed binding energies of excitons in CdS quantum wires with a diameter
of 10 nm reach 170 meV. It is shown that the excitonic transition energy is constant for a wide range of wire diameters.
Pis’ma Zh. éksp. Teor. Fiz. 70, No. 3, 216–220 (10 August 1999) 相似文献
8.
K.?Sudheendran M.?Ghanashyam?Krishna K.?C.?James?Raju 《Applied Physics A: Materials Science & Processing》2009,95(2):485-492
Bismuth Zinc niobate (Bi1.5Zn1.0Nb1.5O7) thin films were deposited by pulsed laser deposition (PLD) method on fused silica substrates at different oxygen pressures.
The structural, microwave dielectric and optical properties of these thin films were systematically studied for both the as-deposited
and the annealed films at 600°C. The as-deposited films were all amorphous in nature but crystallized on annealing at 600°C
in air. The surface morphology as studied by atomic force microscopy (AFM) reveals ultra-fine grains in the case of as-deposited
thin films and cluster grain morphology on annealing. The as-deposited films exhibit refractive index in the range of 2.36–2.53
(at a wavelength of 750 nm) with an optical absorption edge value of 3.30–3.52 eV and a maximum dielectric constant of 11
at 12.15 GHz. On annealing the films at 600°C they crystallize to the cubic pyrochlore structure accompanied by an increase
in band gap, refractive index and microwave dielectric constant. 相似文献
9.
Production and characterization of Nd,Cr:GSGG thin films on Si(001) grown by pulsed laser ablation 总被引:2,自引:0,他引:2
P.R. Willmott P. Manoravi K. Holliday 《Applied Physics A: Materials Science & Processing》2000,70(4):425-429
Nd,Cr:Gd3Sc2Ga3O12 (GSGG) thin films have been produced for the first time. They were grown on Si(001) substrates at 650 °C by pulsed laser
ablation at 248 nm of a crystalline Nd,Cr:GSGG target rod. The laser plume was analyzed using time-of-flight quadrupole mass
spectroscopy, and consisted of elemental and metal oxide fragments with kinetic energies typically in the range 10 to 40 eV,
though extending up to 100 eV. Although films deposited in vacuum using laser fluences of 0.8±0.1 J cm−2 reproduced the Nd,Cr:GSGG bulk stoichiometry, those deposited using fluences above ≈3 J cm−2 resulted in noncongruent material transfer and were deficient in Ga and Cr. Attempts to grow films using synchronized oxygen
or oxygen/argon pulses yielded mixed oxide phases. Under optimal growth conditions, the films were heteroepitaxial, with GSGG(001)[100]∥Si(001)[100],
and exhibited Volmer–Weber-type growth. Room-temperature emission spectra of the films suggest efficient non-radiative energy
transfer between Cr3+ and Nd3+ ions, similar to that of the bulk crystal.
Received: 1 October 1999 / Accepted: 15 October 1999 / Published online: 23 February 2000 相似文献
10.
Nuchjarin Sangwong Weeraya Somphan Prasit Thongbai Teerapon Yamwong Santi Meansiri 《Applied Physics A: Materials Science & Processing》2012,107(2):385-392
Conductive and highly transparent indium tin oxide (ITO) thin films were prepared on photosensitive glass substrates by the
combination of sol–gel and spin-coating techniques. First, the substrates were coated with amorphous Sn-doped indium hydroxide,
and these amorphous films were then calcined at 550∘C to produce crystalline and electrically conductive ITO layers. The resulting thin films were characterized by means of scanning
electron microscopy, UV-Vis spectroscopy, X-ray photoelectron spectroscopy and spectroscopic ellipsometry. The measurements
revealed that the ITO films were composed of spherical crystallites around 20 nm in size with mainly cubic crystal structure.
The ITO films acted as antireflection coatings increasing the transparency of the coated substrates compared to that of the
bare supports. The developed ITO films with a thickness of ∼170–330 nm were highly transparent in the visible spectrum with
sheet resistances of 4.0–13.7 kΩ/sq. By coating photosensitive glass with ITO films, our results open up new perspectives
in micro- and nano-technology, for example in fabricating conductive and highly transparent 3D microreactors. 相似文献
11.
R. Dinu M. Dinescu J.D. Pedarnig R.A. Gunasekaran D. Bäuerle S. Bauer-Gogonea S. Bauer 《Applied Physics A: Materials Science & Processing》1999,69(1):55-61
Ferroelectric SrBi2Ta2O9 (SBT) films were grown by pulsed-laser deposition (PLD) at different substrate temperatures and fluences. A correlation between
film structure and ferroelectric properties is established. The dielectric function ε′ of thin SBT films shows a Curie–Weiss behavior well below the peak temperature Tmax and relaxor-like behavior in the vicinity of Tmax. Domain walls have a strong influence on the dielectric and ferroelectric properties and on the polarization fatigue of SBT
films below 100 °C. The formation of ferroelectric phases is favored at lower substrate temperatures by incorporating Bi2O3 template layers into the structure.
Received: 18 March 1999 / Accepted: 19 March 1999 / Published online: 5 May 1999 相似文献
12.
D. Bharathi Mohan K. Sreejith C.S. Sunandana 《Applied physics. B, Lasers and optics》2007,89(1):59-63
Silver thin films in the thickness range 2–10 nm produced by thermal evaporation onto glass substrates were systematically
iodized and carefully characterized by X-ray diffraction, atomic force microscopy (AFM) and optical absorption spectroscopy.
While the uniodized films are X-ray amorphous in keeping with their quasi-continuous nature and 2D islanded structure, briefly
iodized films showed characteristic beta AgI structure. Most interestingly, AFM of Ag films revealed uniform triangle-shaped
embryos whose shape does not change appreciably upon iodization. Optical absorption spectra of uniodized Ag films show intense
surface plasmon resonance (SPR) features with maxima at 440, 484 and 498 nm for the films of thicknesses 2, 5 and 10 nm, respectively,
with 5 nm films showing properties characteristic of optimally matched dielectric and electronic properties of the substrate
and sample, respectively. Finally, an interesting and unique SPR–exciton phase transition is observed as the ultra-thin films
are progressively iodized. These Ag and AgI films could be promising candidates for plasmonic and nanophotonic applications.
PACS 78.66.-w; 73.20.Mf; 71.35.Cc; 42.70; 68.37.Ps; 42.82.-m 相似文献
13.
H. Hobert H.H. Dunken G. Peiter W. Stier M. Diegel H. Stafast 《Applied Physics A: Materials Science & Processing》1999,69(1):69-76
A large number of thin SiC films, prepared at different conditions by KrF excimer laser ablation of solid SiC targets and
deposition onto Si substrates (some onto quartz glass (QG) and yttrium-stabilized zirconia (YSZ)) were characterized by infrared
and Raman spectroscopy. The films consisted of nano- and microcrystalline SiC and contained nanocrystalline carbon in the
case of QG or YSZ substrates. Raman spectra of nanocrystalline SiC (grains <30 nm) reflect the phonon density-of-state function
of SiC by broad scattering effects at 220–600 and 650–950 cm−1. Medium-size crystallites are represented by a relatively narrow asymmetric band at 790 cm−1 and crystallites >200 nm by an additional asymmetric band at 960 cm−1. Small satellite bands at 760 and 940 cm−1, attributed to SiC surface layers, were resolved in some well-ordered samples. Optical modelling was needed to interpret
the IR spectra. SiC films could be represented by an effective medium model containing a SiC host phase and embedded particles
with free charge carriers. The crystalline order of SiC films can be estimated from the parameters of the SiC oscillators.
Received: 5 October 1998 / Accepted: 8 January 1999 / Published online: 5 May 1999 相似文献
14.
Laser polishing of diamond plates 总被引:5,自引:0,他引:5
S.M. Pimenov V.V. Kononenko V.G. Ralchenko V.I. Konov S. Gloor W. Lüthy H.P. Weber A.V. Khomich 《Applied Physics A: Materials Science & Processing》1999,69(1):81-88
Results are reported on laser polishing of 150–400-μm-thick free-standing diamond films with either a copper vapor laser (510 nm
wavelength) or an ArF excimer laser (193 nm wavelength). Studies were focused on three particular goals. First, we aimed at
a choice of optimum conditions for laser polishing of thick diamond films. It was shown that the laser polishing conditions
and the resulting surface roughness were controlled by varying the angle of incidence of a scanning laser beam and by polishing
time. Second, the laser ablation technique was applied to remove a defective layer from the “substrate” side of the diamond
plates in order to reduce optical losses due to absorption in this layer. Third, the structure of the laser-graphitized diamond
surface was studied using UV, visible, and IR optical spectroscopy techniques in the course of the “step-by-step” oxidative
removal of the graphitic layer with increasing temperature of the oxidation in ambient air. Once the graphitic layer was removed,
the optical transmission in the UV-visible-IR spectral range of the diamond films polished under optimum conditions was measured
and compared with the optical transmission of the mechanically polished diamond films. It was shown that the optical quality
(in the long-wave infrared region) of the laser-polished diamond plates was sufficient to reach the transmittance value very
close to the theoretical limit.
Received: 20 October 1998 / Accepted: 8 March 1999 / Published online: 5 May 1999 相似文献
15.
Fatigue-free Pb(Zr0.52Ti0.48)O3 (PZT) ferroelectric thin films were successfully prepared on indium tin oxide (ITO) coated glass substrates using the sol-gel
method combined with a rapid thermal annealing process (RTA). The films post-annealed at a temperature of 700 °C for 2 min
by RTA process formed (110)-oriented Pb(Zr0.52Ti0.48)O3 thin films with pure perovskite structure, and had a good morphology as well. The good ferroelectricity of the prepared PZT
films was confirmed by P–E hysteresis loop measurements. Fatigue characteristics showed stable behavior. Degradation in polarization
was not found while the repeating cycles were up to 1011, and a low leakage current density of 10−8 A/cm2 was also obtained from the highly fatigue-resisted PZT thin films on ITO/glass substrates.
Received: 19 October 1998 / Accepted: 29 March 1999 / Published online: 26 May 1999 相似文献
16.
S.U. Adikary A.L. Ding H.L.W. Chan 《Applied Physics A: Materials Science & Processing》2002,75(5):597-600
BaxSr1-xTiO3 thin films with a compositional gradient of x=0.3 to 1 (in 0.1 mole fraction increments) were fabricated on Pt/Ti/SiO2/Si substrates using a modified sol–gel technique. The graded film crystallised in a perovskite structure and consists of
a uniform microstructure with comparatively larger grains. The room-temperature relative dielectric constant (εr) and dielectric loss (cosδ) at 100 kHz were found to be 305 and 0.03 respectively. Dielectric peaks were not observed in
the temperature range from -20 °C to 120 °C. The dielectric constant and dielectric loss were almost independent of temperature.
Polarisation–electric field measurements at room temperature revealed a saturated but slim hysteresis loop with a remanent
polarisation (Pr) of 0.6 μC/cm2 and a coercive field (Ec) of 2.4 kV/mm. The graded film behaves as a stack of BaxSr1-xTiO3 capacitors connected in series and hence the dielectric Curie peaks are removed.
Received: 4 October 2001 / Accepted: 17 October 2001 / Published online: 23 January 2002 相似文献
17.
The authors’ endeavors over the last few years with respect to boron nitride (BN) nanotube metal filling are reviewed. Mo
clusters of 1–2 nm in size and FeNi Invar alloy (Fe ∼60 at. %; Ni ∼40 at. %) or Co nanorods of 20–70 nm in diameter were embedded
into BN nanotube channels via a newly developed two-stage process, in which multi-walled C nanotubes served as templates for
the BN multi-walled nanotube synthesis. During cluster filling, low-surface-tension and melting-point Mo oxide first filled
a C nanotube through the open tube ends, followed by fragmentation of this filling into discrete clusters via O2 outflow and C→BN conversion within tubular shells at high temperature. During nanorod filling, C nanotubes containing FeNi
or Co nanoparticles at the tube tips were first synthesized by plasma-assisted chemical vapor deposition on FeNi Invar alloy
or Co substrates, respectively, and, then, the nanomaterial was heated to the melting points of the corresponding metals in
a flow of B2O3 and N2 gases. During this second stage, simultaneous filling of nanotubes with a FeNi or Co melt through capillarity and chemical
modification of C tubular shells to form BN nanotubes occurred. The synthesized nanocomposites were analyzed by scanning and
high-resolution transmission electron microscopy, electron diffraction, electron-energy-loss spectroscopy and energy-dispersive
X-ray spectroscopy. The nanostructures are presumed to function as ‘nanocables’ having conducting metallic cores (FeNi, Co,
Mo) and insulating nanotubular shields (BN) with the additional benefit of excellent environmental stability.
Received: 10 October 2002 / Accepted: 25 October 2002 / Published online: 10 March 2003
RID="*"
ID="*"Corresponding author. Fax: +81-298/51-6280, E-mail: golberg.dmitri@nims.go.jp 相似文献
18.
Application of scanning force microscopy in nanotube science 总被引:2,自引:0,他引:2
J. Muster G.S. Duesberg S. Roth M. Burghard 《Applied Physics A: Materials Science & Processing》1999,69(3):261-267
Recent developments in the application of scanning force microscopy in nanotube science are reviewed. The non-destructive
character of this technique allows the structural characterisation of (chemically modified) single- and multi-wall nanotubes
deposited on substrates for further investigations such as electrical transport measurements. Furthermore, SFM is now an established
tool for manipulation of nanotubes, which allows position control and determination of elastic constants such as the Young’s
modulus. Finally it is shown that very sharp and stable probes for scanning force microscopy can be made from nanotubes due
to their excellent stability and aspect ratio.
Received: 17 May 1999 / Accepted: 18 May 1999 / Published online: 29 July 1999 相似文献
19.
Kuldeep Kumar P. Arun Chhaya Ravi Kant N. C. Mehra Vincent Mathew 《Applied Physics A: Materials Science & Processing》2010,99(1):305-310
Cesium metal clusters strongly affect the optical properties of cesium iodide thin films. The metal clusters are formed during
film formation by thermal evaporation. The cesium cluster of 30–40 nm in the matrix of cesium iodide insulating thin films
results in Surface Plasmon Resonance (SPR). The peak position of these SPR peaks showed a red shift. This was shown to be
due to changes in the dielectric constant of CsI resulting from the strains in the films caused by the metal clusters themselves. 相似文献
20.
R.A. Gunasekaran J.D. Pedarnig M. Dinescu 《Applied Physics A: Materials Science & Processing》1999,69(6):621-624
A parametric study of the growth of La0.5Sr0.5CoO3 (LSCO) thin films on (100) MgO substrates by pulsed-laser deposition (PLD) is reported. Films are grown under a wide range
of substrate temperature (450–800 °C), oxygen pressure (0.1–0.9 mbar), and incident laser fluence (0.8–2.6 J/cm2). The optimum ranges of temperature, oxygen pressure, and laser fluence to produce c-axis oriented films with smooth surface morphology and high metallic conductivity are identified. Films deposited at low
temperature (500 °C) and post-annealed in situ at higher temperatures (600–800 °C) are also investigated with respect to their
structure, surface morphology, and electrical conductivity.
Received: 20 November 1998 / Accepted: 6 July 1999 / Published online: 21 October 1999 相似文献