High-quality a-axis-oriented HgBa2CaCu2Ox superconducting thin films have been grown on (100) LaAlO3 substrates using a modified conventional method that contains a short annealing time of 5 min, rapid-quenching process, and an alternative encapsulated approach. We found that the preferred orientations of HgBa2CaCu2Ox thin films can be controlled by rapid quenching at specific temperatures: 800, 700, 600, and 500 °C. The films rapidly quenched in water from 700 °C during a cooling cycle showed predominantly a-axis orientation perpendicular to the film surface. Phase was confirmed by x-ray diffraction pole figures. The a-axis films exhibited a zero-resistance transition temperature >120 K, which is comparable to epitaxial c-axis-oriented films.

We have used x-ray photoelectron spectroscopy and Auger electron spectroscopy to examine the characteristics of oxides on two types of quasicrystalline Al–Cu–Fe samples. One type was formed by consolidation of powders, resulting in multiple grains with random surface orientations. The other was a single grain, oriented to expose a fivefold surface. Both were oxidized to saturation in a variety of environments at room temperature. We measured the elemental constituents that oxidized, the extent of oxygen-induced Al segregation, and the depth of the oxide. Under the conditions of our experiments, there was little, if any, significant difference between the two types of samples. Hence, surface orientation and bulk microstructure played little or no role on the final state of the oxide under these conditions.

SrTiO3 was investigated as an alternate seed material to grow Pb(Mg1/3Nb2/3)O3–PbTiO3 (PMN–PT) ferroelectric single crystals by seeded polycrystal conversion. Fully dense polycrystalline samples of PMN–32 mol% PT doped with 3 vol% excess PbO were top-seeded with (111) SrTiO3 substrates. Annealing for 10 h at 1150 °C resulted in growth of PMN–32PT single crystals with sizes on the order of several millimeters. Orientation imaging microscopy confirmed that the grown crystal exhibited the same crystallographic orientation as that of the SrTiO3 seed. Elemental distributions analyzed using energy dispersive spectroscopy indicated that interdiffusi on of the relevant elements was negligible.

Modern telecommunications require materials with high dielectric constants (κ). The number of suitable elements ultimately limits one approach to the discovery of new materials, targeting compositions with high atomic polarizabilities (α). By decreasing the molar volume of compositions with high α, however, we anticipated dramatic increases in κ and demonstrated that this approach works. The quenched high-pressure perovskite polymorph of Na2MTeO6 (M = Ti, Sn) showed a twofold increase in κ, compared to the ilmenite form. This result suggested the highest values of κ occur for compositions with high α, which form quenchable compounds at high pressures and temperatures.

A (110)-oriented diamond film was deposited by hot filament chemical vapor deposition with H2 and CH4 separately introduced into the reactive zone. The film with a degree of orientation I(220)/I(111) of more than 200% and deposition rate of 2–3 μm/h was obtained for a deposition time of 17 h. The long deposition time enlarged the grain size and enhanced the degree of orientation, but too long a deposition time resulted in random growth. The temperature field was measured and also calculated using a simple model. Both results showed that a temperature field existed with varied gradients along the normal of substrate surface. The (110)-oriented diamond film was deposited in the zone with negative temperature gradient. The change in orientation occurring for long deposition times was ascribed to the change of temperature gradient.

The values of effective activation energy (Q) and pre-exponential factor (D0) reported in the literature for diffusion in the novel bulk metallic glasses, both in the glassy and the deeply supercooled liquid regions, are found to follow the same correlation as reported earlier in conventional metallic glasses, namely D0 = A exp(Q/B), where A and B are fitting parameters with values A = 4.8 × 10−19 m2 s−1 and B = 0.056 eV atom−1. A possible explanation for the observed values of A and B is given by combining an activation energy and a free volume term. The interpretation favors a cooperative mechanism for diffusion in the glassy and deeply supercooled liquid states.

Nanocrystalline diamond has been synthesized on a mirror-polished Si(001) substrate by means of direct ion beam deposition. Low-energy (80–200 eV) hydrocarbon and hydrogen ions, generated in a Kaufman ion source, were used to bombard the substrates. The bombarded samples were characterized by high-resolution transmission electron microscopy and Raman spectroscopy. Nanocrystalline diamond particles of random orientation were observed in a matrix of amorphous carbon film on the Si(001) substrate. The size of the nanocrystalline diamond particles varied in the range of 50–300 Å. The mechanism of ion-induced formation of nanocrystalline diamond is discussed.

Plasma treatment was applied on glasslike carbon spheres to modify their gas adsorption behavior. After the oxygen plasma treatment, a selective adsorption of CO2 gas was obtained, almost no nitrogen adsorption being detected, at low temperatures. Surface morphology observed by using field-emission scanning electron microscopy, atomic force microscopy, and scanning tunneling microscopy was found to be changed after the oxygen plasma treatment.

A systematic investigation of the boron doping of microwave-plasma-deposited diamond films was performed. Doping with levels up to 550 ppm was carried out in situ on undoped diamond film substrates in a microwave-plasma-assisted chemical vapor deposition with liquid trimethyl-, triethyl-, and tripropylborate and gaseous trimethylborane as doping sources. The dependence of the boron incorporation probability on the doping sources and on the process parameters was studied with secondary ion mass spectrometry. The doping-induced variations of phase quality and morphologic characteristics of the boron-doped diamond layers were investigated by means of scanning electron microscopy and Ramon spectroscopy. The incorporation of other impurities (i.e., hydrogen, nitrogen, oxygen, and silicon) were also determined by secondary ion mass spectrometry. The relations of the concentration of these impurities to the boron incorporation were also studied.

Using direct carbon ion beam deposition, in situ surface modification was performed by an energetic C- beam (400 and 500 eV) prior to amorphous carbon film growth to enhance adhesion of the film. It has been found from high-resolution electron microscopy that the C and Si mixing layer at the interface causes strong adhesion of the film. Electron energy loss spectroscopy was used to investigate chemical states of the C and Si mixing layer at the interface. The carbon composition profile in silicon showed that the thickness of the mixing layer was about 30 nm for 500 eV modification (at 200 °C). Silicon L-edge study at the C/Si interface found C–Si bond formation only at the surface of silicon over 2–3-nm-thick layers. The C–Si bond formation is a function of C- ion impingement energy. The thickness of the bonding layer decreased to less than 1 nm for 400 eV surface modification. When the substrate was modified by a 500-eV C- beam at 800 °C, the thickness of the SiC layer was about 10 nm. C–Si bond formation was enhanced by the supplemental thermal energy.

The relationship between the defect microstructure of SiC films grown by solid-source molecular-beam epitaxy on 4H and 6H–SiC substrates and their growth conditions, for substrate temperatures ranging between 950 and 1300 °C, has been investigated by a combination of transmission electron microscopy and atomic force microscopy. The results demonstrate that the formation of defective cubic films is generally found to occur at temperatures below 1000 °C. At temperatures above 1000 °C our investigations prove that simultaneous supply of C and Si in the step-flow growth mode on vicinal 4H and 6H substrate surfaces results in defect-free hexagonal SiC layers, and defect-free cubic SiC can be grown by the alternating deposition technique. The controlled overgrowth of hexagonal on top of cubic layers is demonstrated for thin layer thicknesses.

Nanoparticles of ZnS capped with tri-n-octylphosphineoxide (TOPO) and close to monodispersed have been prepared by a single-source route using ethyl(di-ethyldithiocarbamato)zinc(II) as a precursor. The nanoparticles obtained showed quantum size effects in their optical spectra, and the photoluminescence spectrum showed a broad emission that could be attributed to the surface traps. A blue shift of 0.31 eV in relation to the bulk material was observed. The selected area electron diffraction, x-ray diffraction pattern and transmission electron microscopy showed the material to be of the zinc blend structure. The crystallinity of the material was also evident from high-resolution transmission electron microscopy, which gave well-defined images of nano-sized particles with clear lattice fringes and a spacing of approximately 3 Å, corresponding to the (111) planes of the cubic crystalline ZnS phase and in the size range of 3.9–4.9 nm. The presence of strong phosphorus peak in the energy dispersion analytical x-ray pattern, together with a shift in infrared band for P = O of TOPO showed that the particles were TOPO capped.

Pulsed laser deposition (PLD) of Ir thin films has been achieved by ablating an iridium target with a KrF excimer laser. The iridium deposition rate was investigated, over the (0.4–2) × 109 W/cm2 laser intensity range, and found to reach its maximum at (1.6 ± 0.1) × 109 W/cm2. At this laser intensity, the PLD Ir films were deposited at substrate deposition temperatures ranging from 20 to 600 °C. The PLD Ir films exhibited a (111) preferentially oriented polycrystalline structure with their average grain size increasing from about 10 to 30 nm as the deposition temperature was raised from 20 to 600 °C. Their mean surface microroughness (Ra) was found to change from an average value of about 1 nm in the 20–400 °C temperature range to a value of about 4.5 nm at 600 °C. As the deposition temperature is varied from 20 to 600 °C, not only does the stress of PLD Ir films change drastically from highly compressive (−2.5 GPa) to tensile (+0.8 GPa), but their room-temperature resistivity also gradually decreases in the 20–400 °C range and stabilizes for higher temperatures. In the 400–600 °C range, the resistivity of PLD Ir films was as low as 6.0 ± 0.2 μΩ cm, which is very close to the iridium bulk value of 5.1 μΩ cm. Thus, PLD Ir films exhibiting not only the lowest resistivity but also a nearly zero stress level can be grown at a deposition temperature of about 400 °C. The resistivity of the PLD Ir films can be described by a grain boundary scattering model.

We have analyzed the anisotropic behavior of surface roughening in Si1−xGex/Si(001) heterostructures by use of methods of elastic analysis of undulated surfaces and perturbation analysis on the basis of global energy variations associated with surface evolution. Both methods have shown that the two-dimensional stage of surface roughening preferentially takes place in the form of ridges aligned along the two orthogonal 〈100〉 type directions. This prediction has been confirmed by ex situ experimental observations of surface evolution by use of atomic force microscopy and transmission electron microscopy in both subcritically and supercritically thick Si1−xGex films grown on Si(001) substrates. Further experiments in supercritically thick films have revealed a remarkable interplay between defect formation and surface evolution: the formation of a network of 〈110〉?misfit dislocations in the latter stages alters the evolution process by rotating the ridge formations toward the 〈110〉 type directions.

Ingots of composition Nd9Fe85B6, Nd9Fe85B6 + 1 at.% (Ti + C), Nd9Fe85B6 + 2 at.% (Ti + C), and Nd9Fe85B6 + 5 at.% (Ti + C) were prepared by plasma arc-melting the constituent elements from 99.95 wt% Nd, 99.99 wt% Fe, 99.97 wt% Ti, spectrographic grade C, and ferroalloy Fe–B (19.6 wt% B). Effect of Ti + C addition and its content on quenchability and magnetic properties of Nd9Fe85B6 alloy were investigated by melt-spinning. The results showed that the added Ti and C elements reacted with each other to form TiC compound that was solid solutioned, precipitated, or both in the cast ingots. The Ti + C addition can increase the glass-forming ability (GFA) of an α–Fe/Nd2Fe14B–type nanocomposite permanent material: the more the additive, the stronger the GFA; but only approximately 2 at.% Ti + C addition could enormously increase the magnetic properties.

The microstructure of sputtered 10-nm thin films of equiatomic binary alloys of CoPt and FePt was characterized using transmission electron microscopy (TEM). Grain growth kinetics was examined using manual and digital analysis of bright-field TEM images and was seen to take two stages during annealing in these films. A rapid growth stage concurrent with the formation of a [111] fiber texture was observed to occur within the first 5–10 min of annealing, followed by a much slower growth stage after the fiber texturing was well advanced. Differences in grain growth rate and ultimate grain size were also observed to depend on heating rate.

A totally new technique of surface modification—thermal surface-alloying treatment for pure copper—was developed. A 0.2–1.8 mm copper alloy layer, which has a hardness 4 to 5 times higher than the pure copper substrate, was formed after the treatment. The significance of this technique is that the surface of pure copper can be efficiently hardened without significant reduction of the overall thermal and electrical conductivity. Variations of composition and microstructure in the alloy layer were studied after pure copper was surface alloy treated with aluminum.

A nanocrystalline PbTiO3 particle/organic hybrid was synthesized through hydrolysis and polymerization of metalorganic compounds below 100 °C. The PbTiO3 precursor was synthesized from lead methacrylate and titanium isopropoxide. The formation of a Pb–Ti complex alkoxide was confirmed by H and Pb nuclear magnetic resonance spectroscopy. Hydrolyzed Pb–Ti alkoxide was polymerized, yielding the PbTiO3 particles/oligomer hybrid. The organic matrix included nano-sized crystalline particles, depending on the hydrolysis conditions. The nanocrystalline particles were identified to be lead titanate by electron diffraction and energy-dispersive x-ray analysis. The dielectric constant of the nanometer-sized PbTiO3/oligomer hybrid was 5.2 at 10 kHz.

In this paper, we show the feasibility of the pulsed-laser ablation technique to grow 20–30-nm-thick, discrete and continuous coatings on particulate material systems so that the properties of the core particles can be suitably modified. Experiments were conducted with a pulsed excimer laser (λ = 248 nm, pulse duration = 25 ns) to deposit nanoparticle coatings on Al2O3 and SiO2 core particles by irradiation of Ag and Y2O3–Eu3+ sputtering targets. Structural characterization was performed with scanning electron microscopy, wavelength dispersive x-ray mapping, transmission electron microscopy, and scanning transmission electron microscopy with z-contrast.

To increase the toughness of a metallic glass with the nominal composition Zr57Nb5Al10Cu15.4Ni12.6, it was used as the matrix in particulate composites reinforced with W, WC, Ta, and SiC. The composites were tested in compression and tension experiments. Compressive strain to failure increased by more than 300% compared with the unreinforced Zr57Nb5Al10Cu15.4Ni12.6, and energy to break of the tensile samples increased by more than 50%. The increase in toughness came from the particles restricting shear band propagation, promoting the generation of multiple shear bands and additional fracture surface area. There was direct evidence of viscous flow of the metallic glass matrix within the confines of the shear bands.