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1.
We report electrohydrodynamic jet (E-jet) printing of a commercialised silver nano-ink in fully voltage-controlled fashion.
Metallic pads and conducting tracks with hundred-micron feature size were drop-on-demands produced on Si substrates. Layer-by-layer
printing was further performed, demonstrating a capability in creating 3D multistructures. Planar pattern with a large inductance
of 2.5 μH and an excellent resistivity of 4.2×10−8 Ω m was fabricated, showing a true inductive device. Our result demonstrates a feasibility of E-jet printing in the application
of smart electronic devices fabrication. 相似文献
2.
Yingbang Yao Bernd Ploss C. L. Mak K. H. Wong 《Applied Physics A: Materials Science & Processing》2010,99(1):211-216
BiFeO3 (BFO) ceramics were prepared by a modified solid-state-reaction method which adopts a higher heating/cooling rate during
the sintering process than usually used. It was found that the calcination temperature T
cal (from 400 to 750°C) does not influence the BFO phase formation, while the sintering temperature T
sin (from 815 to 845°C) dominates the phase purity. The optimum sintering temperature was in the range from 825 to 835°C. The
optimized samples exhibit saturated ferroelectric hysteresis loops with a remnant polarization of 13.2 μC/cm2. The measured piezoelectric coefficient d
33 was 45 pC/N. No remnant magnetization was observed in all of the samples. The pyroelectric properties were studied as a function
of temperature and frequency. A pyroelectric coefficient as high as 90 μC/m2 K was obtained at room temperature in the optimized sample. An abrupt decrease of the pyroelectric coefficient was observed
at temperatures between 70 and 80°C. On the basis of our results, BFO may have the potential for pyroelectric applications. 相似文献
3.
Wen-Chi Lin Shi-Hwa Huang Chang-Long Chen Chih-Chia Chen Din Ping Tsai Hai-Pang Chiang 《Applied Physics A: Materials Science & Processing》2010,101(1):185-189
It is demonstrated that the surface-enhanced Raman scattering (SERS) intensity of R6G molecules adsorbed on a Ag nanoparticle
array can be controlled by tuning the size and height of the nanoparticles. A firm Ag nanoparticle array was fabricated on
glass substrate by using nanosphere lithography (NSL) combined with reactive ion etching (RIE). Different sizes of Ag nanoparticles
were fabricated with seed polystyrene nanospheres ranging from 430 nm to 820 nm in diameter. By depositing different thicknesses
of Ag film and lifting off nanospheres from the surface of the substrate, the height of the Ag nanoparticles can be tuned.
It is observed that the SERS enhancement factor will increase when the size of the Ag nanoparticles decreases and the deposition
thickness of the Ag film increases. An enhancement factor as high as 2×106 can be achieved when the size of the polystyrene nanospheres is 430 nm in diameter and the height of the Ag nanoparticles
is 96 nm. By using a confocal Raman mapping technique, we also demonstrate that the intensity of Raman scattering is enhanced
due to the local surface plasmon resonance (LSPR) occurring in the Ag nanoparticle array. 相似文献
4.
《Current Applied Physics》2010,10(4):1005-1008
Silver (Ag) nanoparticles (∼3 nm) were synthesized using silver nitrate as the starting precursor, ethylene glycol as solvent and poly (N-vinylpyrrolidone) (PVP) introduced as a capping agent. These nano-Ag particles were reinforced in nylon matrix by electrospinning of nylon-6/Ag solution in 2,2,2-trifluoroethanol and composite nanofibrous membranes were synthesized. The effects of solution concentration and relative humidity (RH) on the resultant fibrous membranes were studied. Scanning electron microscopy and Transmission electron microscopy was used to study the size and morphology of the fibers. It was observed that concentration and RH could be used to modulate the fiber diameter. Tensile test was used to evaluate the mechanical property of these electrospun composite membranes. The composite membranes showed higher strength (approx. 2–3 times increase in strength) compare to as synthesized nylon fibers. 相似文献
5.
SmAlO3 nanocrystalline powders were successfully synthesized by the polymeric precursor method using ethylenediaminetetraacetic
acid as a chelating agent. The precursor and the derived powders were characterized by thermogravimetry analysis (TG) and
differential scanning calorimetry analysis (DSC), infrared spectroscopy (IR), X-ray diffractometry (XRD) and transmission
electron microscopy (TEM). The results showed that pure SmAlO3 powder with orthorhombic perovskite structure could be synthesized at 800°C for 2 h without formation of any intermediate
phase. The average particle size of the powder synthesized at 900°C was as low as 28 nm. Subsequently, the bulk SmAlO3 ceramics were prepared at various sintering temperatures using the synthesized powders calcined at 900°C for 2 h as starting
materials. The sintering experiments indicated that the sample sintered at 1550°C for 2 h exhibited the highest relative density
of 97.2% and possessed the best microwave dielectric properties of ε
r=20.94, Q×f=78600 GHz and τ
f=−71.8 ppm/°C. 相似文献
6.
F. M. Pontes M. S. Galhiane L. S. Santos A. Gavino L. A. Petit D. S. L. Pontes E. Longo A. J. Chiquito C. E. F. Costa 《Applied Physics A: Materials Science & Processing》2009,95(3):693-698
The dependence of ferroelectric phase transition temperature as a function of strontium substitution in lead titanate zirconate
thin films (referred here as PSZT) on platinum-coated silicon substrates was investigated. The dielectric study reveals that
the material undergoes a diffuse type ferroelectric phase transition that depends on the substitution of Sr for Pb in PZT.
At 100 kHz, the phase transition temperatures were 633, 613 and 516 K for PSZT10, PSZT20 and PSZT30 thin films, respectively.
On the other hand, the results showed that the dependence of the dielectric constant upon the frequency does not reveal any
relaxor behavior. The diffusivity increases with increasing Sr contents in the studied composition range. The experimental
data obtained from measurements of the dielectric constant as a function of temperature and frequencies showed a classical
behavior of ferroelectric phase transition in PSZT thin films, rather than a relaxor ferroelectric phase transition. The transition
temperature decreases with increasing Sr contents due to the decrease in grain size, lattice decrease and local structural
disorder. 相似文献
7.
《Solid State Ionics》1988,27(3):207
In the above [1] article, an earlier work “Low Temperature Synthetic Studies of β-Aluminas”, on this subject [2], with similar results but with much more interpretation of the X-ray patterns, was not cited. The readers are referred to it for more details. 相似文献
8.
Deok Kyu Kim Kyeong Min Kim Choon Bae Park 《Applied Physics A: Materials Science & Processing》2010,98(4):913-917
A p-type ZnO thin film was prepared using arsenic diffusion via the ampoule-tube method. This was followed by fabrication
of a ZnO p–n homojunction using n-type ZnO and characterization of the device properties. The ZnO thin film exhibited p-type
characteristics, with a resistivity of 2.19×10−3 Ω cm, a carrier concentration of 1.73×1020/cm3, and a mobility of 26.7 cm2/V s. Secondary ion mass spectrometer analysis confirmed that in- and out-diffusion occurred simultaneously from the external
As source and the GaAs substrate. The device exhibited the rectification characteristics of a typical p–n junction; the forward
voltage at 20 mA was approximately 5.5 V. The reverse-bias leakage current was very low—0.1 mA for −10 V; the breakdown voltage
was −11 V. The ampoule-tube method for fabricating p-type ZnO thin films may be useful in producing ultraviolet ZnO LEDs and
other ZnO-based devices. 相似文献
9.
10.
Surasing Chaiyakun Artorn Pokaipisit Pichet Limsuwan Boonlaer Ngotawornchai 《Applied Physics A: Materials Science & Processing》2009,95(2):579-587
Titanium dioxide thin films were deposited on three different unheated substrates by unbalanced magnetron sputtering. The
effects of the sputtering current and deposition time on the crystallization of TiO2 thin films were studied. The TiO2 thin films were deposited at three sputtering current values of 0.50, 0.75, and 1.00 A with different deposition times of 25,
35, and 45 min, respectively. The surface morphology of the films was investigated by atomic force microscopy (AFM). The structure
was characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The film thickness was determined
by field emission scanning electron microscopy (FE-SEM), and the optical property was evaluated with spectroscopic ellipsometry.
The results show that polycrystalline anatase films were obtained at a low sputtering current value. The crystallinity of
the anatase phase increases as the sputtering current increases. Furthermore, nanostructured anatase phase TiO2 thin films were obtained for all deposition conditions. The grain size of TiO2 thin films was in the range 10–30 nm. In addition, the grain size increases as the sputtering current and deposition time
increase. 相似文献
11.
V. ?vr?ek T. Sasaki R. Katoh Y. Shimizu N. Koshizaki 《Applied physics. B, Lasers and optics》2009,94(1):133-139
Blue luminescent colloidal silicon nanocrystals (Si-ncs) were synthesized at room temperature by nanosecond pulsed laser ablation
of a single-crystal silicon target in de-ionized water. Irregular Si-nc fragments obtained by laser ablation are stabilized
into regularly shaped, spherical, and well-separated aggregates during the aging process in water. Aging in de-ionized water
for several weeks improved the photoluminescence (PL) intensity. At least two weeks of aging are necessary for observation
of broad blue room temperature PL with a maximum centered at 420 nm. Detailed structural analysis revealed that agglomerates
after aging for several months contain Si-ncs with irregular shape smaller than the quantum confinement limit (<5 nm). These
blue luminescent Si-ncs dispersed in de-ionized water exhibited a PL decay time of 6 ns, which is much faster than that of
Si-ncs prepared in traditional ways (usually on the order of microseconds). The oxidized Si-ncs with quantum confinement effects
are responsible for a PL band around 400 nm visible to the naked eye at room temperature. 相似文献
12.
J. A. González J. P. Andrés J. A. De Toro P. Mu?iz T. Mu?oz O. Crisan C. Binns J. M. Riveiro 《Journal of nanoparticle research》2009,11(8):2105-2111
The technique of gas-phase aggregation has been used to prepare partially oxidized Co nanoparticles films by allowing a controlled
flow of oxygen gas into the aggregation zone. This method differs from those previously reported, that is, the passivation
of a beam of preformed particles in a secondary chamber and the conventional (low Ar pressure) reactive sputtering of Co to
produce Co–CoO composite films. Transmission electron microscopy shows that the mean size of the particles is about 6 nm.
For sufficiently high oxygen pressures, the nanoparticles films become super-paramagnetic at room temperature. X-ray diffraction
patterns display reflections corresponding to fcc Co and fcc CoO phases, with an increasing dominance of the latter upon increasing
the oxygen pressure in the aggregation zone, which is consistent with the observed reduction in saturation magnetization.
The cluster films assembled with particles grown under oxygen in the condensation zone exhibit exchange-bias fields (about
8 kOe at 20 K) systematically higher than those measured for Co–CoO core-shell nanoparticles prepared by oxidizing preformed
particles in the deposition chamber, which we attribute, in the light of results from annealing experiments, to a higher ferromagnetic–antiferromagnetic
(Co–CoO) interface density. 相似文献
13.
Z. Fleischman C. Munasinghe A. J. Steckl A. Wakahara J. Zavada V. Dierolf 《Applied physics. B, Lasers and optics》2009,97(3):607-618
Using combined excitation emission spectroscopy, we performed a comparative study of europium ions in GaN in samples that
have been in situ doped during interrupted growth epitaxy (IGE) or conventional molecular beam epitaxy (MBE) as well as samples
that were grown using organometallic vapor phase epitaxy (OMVPE) and subsequently ion implanted with Eu ions. Through site-selective
resonant excitation, we are able to unambiguously assign all major observed transitions to a combination of different incorporation
sites and electron–phonon coupled transitions. We identified at least nine different incorporation sites of Eu ions in GaN
and studied how these sites behave under different excitation conditions and how their relative number is modified by different
growth and doping conditions. The coupling to phonons has also been studied for a series of Al
x
Ga1−x
N samples with x=0…1. We find that a main site most resembling an unperturbed Eu ion on Ga site is always dominant, while the minority sites
are changing substantially in relative numbers and can occur in some samples fairly close in emission intensity to the main
site. In terms of the excitation pathway after the creation of electron-hole pairs, we found three types of centers: (1) sites
that are dominantly excited through shallow defect traps; (2) sites that are excited through a deep defect trap; (3) sites
that cannot be excited at all including the majority of the main sites. We interpret this finding to indicate that the ion
in this environment is not very efficient in trapping excitation and that the indirect excitation involving other traps depends
on the ion/trap distance. Many of the main sites are far away from these traps and cannot be excited through this channel
at all. The efficiency of excitation is highest for the deep traps, indicating that it would be desirable to enrich the respective
site, as has been done with some success in the IGE grown samples. 相似文献
14.
Layered CoO/Co(7 nm)/Cu(6 nm)/Co(7 nm) spin-valve systems capped by a 5 nm boron top layer, which exhibit giant magnetoresistance (GMR), were prepared by pulsed laser deposition (PLD) with a 193 nm ArF excimer laser. To reduce atomic intermixing at the various layer interfaces, the areal energy density of the laser was lowered to 4.2 J/cm2 for the first 2 nm of the intermediate Cu and the Co top layers, while applying 11 J/cm2 for the rest. By this procedure, a clear improvement of the GMR could be accomplished as compared to an identical reference system prepared by exclusively applying the high value of 11 J/cm2, pointing to the importance of minimizing interface mixing.Additionally, the effect of the laser intensity on the areal density and shape of m-sized droplets co-deposited onto the substrates by PLD was studied. It turned out that for the two limiting values applied in the present case, no negative influence of the droplets on the magnetic hysteresis of pure Co layers or spin-valve systems could be observed. PACS 81.15.Fg; 75.47.Np; 75.70.Cn 相似文献
15.
Masaki Oba Yoichiro Maruyama Katsuaki Akaoka Masabumi Miyabe Ikuo Wakaida 《Applied Physics A: Materials Science & Processing》2010,101(3):545-549
Emission characteristics of gadolinium (Gd) oxide are studied, using ns and fs laser pulses for ablation in double-pulse laser
induced breakdown spectroscopy (LIBS). In the current conditions of pulse energy and signal detection timing, emission intensity
enhancement in the reheating mode is 25-fold, but little effect can be observed in a pre-pulse mode. It is shown that the
optimum focus position of the ablation pulse is about 5 mm apart from the sample surface in the reheating mode. Although little
emission can be observed in the single-pulse configuration with fs ablation pulses, the intense emission can be observed in
the reheating mode in the double-pulse configuration. 相似文献
16.
Ali Akbar Ashkarran Azam Iraji?zad Seyed Mohammad Mahdavi Mohammad Mahdi Ahadian 《Applied Physics A: Materials Science & Processing》2010,100(4):1097-1102
ZnO nanostructures were synthesized through arc discharge of zinc electrodes in deionized (DI) water. X-ray diffraction (XRD)
analysis of the prepared nanostructures indicates formation of crystalline ZnO of hexagonal lattice structures. Transmission
electron microscopy (TEM) images illustrate rod-like as well as semi spherical ZnO nanoparticles with 15–20 nm diameter range,
which were formed during the discharge process with 5 A arc current. The average particle size was found to increase with
the increasing arc current. X-ray photoelectron spectroscopy (XPS) analysis confirms formation of ZnO at the surface of the
nanoparticles. Surface area of the sample prepared at 5 A arc current, measured by BET analysis, was 34 m2/g. Photodegradation of Rhodamine B (Rh. B) shows that the prepared samples at lower currents have a higher photocatalytic
activity due to larger surface area and smaller particle size. 相似文献
17.
ZF, LF and TF SR experiments with antiferromagnetic (AF) ceramical samples La2–x
Sr
x
CuO4–y
have been performed in the temperature range 10–300 K. Zero field muon spin polarization functions obtained below the Neel temperature clearly show a nonzero initial precession phase-–0.35 rad. We propose an explanation based on existence of the dynamical magnetic fields on the muon.We thank Drs. A.G. Chistov and A.M. Brjazkalo from RSC Kurchatov Institute for the preparation the #2 La2CuO4–y
sample. 相似文献
18.
《Comptes Rendus de l''Academie des Sciences Series IV Physics》2000,1(4):479-491
We have elaborated organic–inorganic hybrid light-emitting diodes (HLED). These devices emitting in the green are formed of two hybrid thin layers, exhibiting different functionalities, which are sandwiched between indium–tin oxide (ITO) and metallic electrodes. These layers have been prepared from silane precursors modified with hole transporting units and light-emitting naphthalimide moieties by the sol–gel technique. The hole transporting sol–gel layers exhibit about the same charge mobility as organic polymers having equivalent active units. The maximum external quantum efficiency of the best diode using LiF/Al cathode is about 1% and the luminance reaches 4000 cd · m −2 . 相似文献
19.
Hong-Son Chu Wei-Bin Ewe Boris S. Luk’yanchuk Er-Ping Li 《Applied Physics A: Materials Science & Processing》2010,100(2):353-357
We investigate, at the visible violet wavelength of 400 nm, the localized field-enhancement properties of an optical antenna
consisting of two coupled metallic nanoparticles placed on the silica substrate. Compared to other shapes of optical antennas
such as bowtie and coupled elliptical rods, the coupled semi-nanocapsules exhibit a stronger field-intensity enhancement in
the gap and relatively weak field intensity at the outer-ends. Furthermore, the intensity enhancement of the semi-nanocapsules
antenna can be further enhanced by choosing the suitable direction of illumination. These proposed structures can be used
for the design and the applications of an optical antenna at the visible violet wavelength. 相似文献
20.
Properties of negative thermal expansion β-eucryptite ceramics prepared by spark plasma sintering 下载免费PDF全文
β-eucryptite powders are prepared by the sol-gel method through using tetraethoxysilane lithium nitrate and aluminum isopropoxide as starting materials. β-eucryptite ceramics are prepared by spark plasma sintering. The effects of sintering temperature on the negative thermal expansion properties of the β-eucryptite are investigated by x-ray diffraction(XRD), scanning electron microscopy, and thermal expansion test. The XRD results exhibit no change in the crystal structure of the sample prepared by different sintering processes. The negative thermal expansion properties increase with the increase of the sintering temperature. The coefficient of thermal expansion of β-eucryptite ceramics sintered at 1100℃ is calculated to be -4.93 × 10~(-6)℃~(-1). Crystallization behaviors of the ceramics may play an important role in the increase of negative thermal expansion of β-eucryptite. High sintering temperature could improve the crystallization behaviors of the ceramics and reduce the residue glass phase, which can improve the negative thermal expansion properties of β-eucryptite ceramics. 相似文献