In this paper we review the achievements in the field of silicon crystalline thin film solar cells and correlate these with the different types of growth techniques and substrates. As a starting point we discuss the characteristics of photovoltaic devices based on the use of highly doped monocrystalline substrates as mechanical carriers for the thin films. These films are epitaxially deposited from the gas (CVD) or liquid phase (LPE). The comparison of both techniques is extended to growth on defective silicon substrates, i.e., multicrystalline wafers or silicon ribbons. The intrinsic grain boundary recombination activity in the thin films is assessed as a function of the deposition technique. Bulk passivation by hydrogenation considerably improves the recombination properties. The optimization of the hydrogen passivation conditions is looked at in conjunction with the used surface passivation process. This review is completed with the approaches to realize thin film cells on nonsilicon substrates, including recrystallization in solid and liquid phases.

Microstructures of 27-filament (Bi, Pb)2Sr2Ca2Cu3O10+x (BPSCCO 2223) tape at various stages of repetitive rolling and sintering have been investigated using TEM and SEM. It was found that the dislocation density increases with increasing sintering time with the maximum dislocation density of 1012/cm2 achieved for tapes sintered for 220 h. The interface between Ag-sheath and oxide core was observed to be wavelike. Small irregular 2223 colonies and cracks in the oxide cores were often observed near the Ag-sheath/oxide core interface. Repetitively rolled and sintered specimen with a total sintering time of 220 h was observed to have optimum phase purity of 2223 phase. Prolonged sintering results in recrystallization of the 2223 grains, degrading the texture of the oxide core.

This review provides a comprehensive evaluation of the state-of-knowledge of radiation effects in crystalline ceramics that may be used for the immobilization of high-level nuclear waste and plutonium. The current understanding of radiation damage processes, defect generation, microstructure development, theoretical methods, and experimental methods are reviewed. Fundamental scientific and technological issues that offer opportunities for research are identified. The most important issue is the need for an understanding of the radiation-induced structural changes at the atomic, microscopic, and macroscopic levels, and the effect of these changes on the release rates of radionuclides during corrosion.

High-temperature x-ray diffraction measurements of a (Bi, Pb)-2223 precursor mixture used to produce high-Jc superconducting tapes were conducted on silver and ZrO2 substrates. The precursor mixture consisted primarily of 2212, Ca2PbO4, and CuO. Phase evolution was markedly sensitive to oxygen partial pressure: In 10% O2 growth of the 2223 phase on silver was rapid, proceeded at the expense of the 2212 phase, and was preceded by the disappearance of the Ca2PbO4 phase. When slowly heated on a silver substrate in 7.5% O2 the 2212 phase melted near 800 °C and subsequently recrystallized near 820 °C in a highly textured form, but with no detectable 2223 formation. Under similar conditions on a ZrO2 substrate, the mixture exhibited no marked changes in the XRD patterns up to 850 °C. The dramatic reactivity on silver was also highly dependent on heating rate; rapid heating in 7.5% O2 to 825 °C did not result in melting of the 2212 phase or appearance of the 2223 phase. In experiments leading to formation of 2223, the c-lattice parameter of the 2212 phase contracted just prior to the onset of formation of 2223. This result is consistent with the formation of an intermediate Pb-doped phase of 2212. A transient amorphous phase appeared briefly at the onset of formation of 2223. No evidence for intergrowth conversion of 2212 to 2223 was observed.

Epitaxially grown LiNbO3 thin films were prepared on sapphire(012) (R-plane) substrates by a dipping-pyrolysis process using two kinds of lithium sources, i.e., Li-2-ethylhexanoate and Li-trifluoroacetate, which are pyrolyzed in air to Li2CO3 and LiF, respectively. Crystallization temperature and alignment of LiNbO3 films on sapphire(012) were found to depend greatly on the Li sources. Dominantly [100]-oriented epitaxial LiNbO3 films were crystallized at around 600 °C using 2-ethylhexanoate, whereas dominantly [012]-oriented epitaxial LiNbO3 films resulted at a temperature as low as 400 °C using trifluoroacetate.

Depth-sensing indentation measurements are performed with two different Vickers indenters and one Berkovich indenter. The sample materials were mirror polished Ag, Al, Au, Ni, and Ti samples. From the load-indentation depth data, the conventional hardness plots as well as the first derivative are calculated. The latter procedure yields a specific volume related density of deformation energy in the probed material. That specific energy density is shown to be a constant material parameter for extended indentation depths and for different Vickers indenters. Vickers and Berkovch indenters delivered within the error margin the same results.

An anomalous increase of current was found in Fe-doped titania ceramics subjected to a constant field of 105 V/m. It is suggested that the space charge rises from blockage of O2(g) → O2−(s) ion transfer at the cathode. This leads to an increase of n-conductivity in the cathodic region and p-conductivity in the anodic region according to the specific defect equilibrium. This viewpoint was reinforced by two newly observed phenomena: (i) the I-V plot shows a linear feature at the initial stage, but it gradually becomes a rectifying feature with time; and (ii) an edge-located electrode shows lower current density and faster current saturation compared with a normal electrode.

When a melt of BaO and CuO mixture was infiltrated into sintered Y2BaCuO5(211) compact to form YBa2Cu3Ox(123) superconductor, butterfly-like plane patterns of 211-free regions were observed to form within growing 123 grains. In a 123 grain, the 211-free region was found to be a pair of vertex-shared pyramids and 211 entrapped region to be the rest of the bulk of the grain. An observation of patterns and cracks formed within 123 grains revealed the base of the pyramids to be (001) plane. The difference in entrapment, which depends on crystallographic planes and results in the formation of the pattern, was explained by the dihedral angles between 123 and 211. The dihedral angle between a - (or b-) plane and 211, which is believed to be greater than zero degree, might cause the entrapment of 211 particles in a [100] (or [010]) direction. In contrast, the dihedral angle of most probably zero degree between c-plane and 211 inhibited the entrapment. The observed shape of 211 particles in front of a-(or b-) and c-planes supports the above explanation of 211 entrapment to form the butterfly-like patterns. was explained by the dihedral angles between 123 and 211. The dihedral angle between a- (or b-) plane and 211, which is believed to be greater than zero degree, might cause the entrapment of 211 particles in a [100] (or [010[) direction. In contrast, the dihedral angle of most probably zero degree between c-plane and 211 inhibited the entrapment. The observed shape of 211 particles in front of a-(or b-) and c-planes supports the above explanation of 211 entrapment to form the butterfly-like patterns.

The sputter-induced epitaxy change of in-plane orientation occurring in YBa2Cu3O7-x (001) thin films grown on MgO (001) substrates by pulsed organo-metallic beam epitaxy (POMBE) is investigated by a series of film growth and characterization experiments, including RBS and TEM. The factors influencing the orientation change are systematically studied. The experimental results suggest that the substrate surface morphology change caused by the ion sputtering and the Ar ion implantation in the substrate surface layer are not the major factors that affect the orientation change. Instead, the implantation of W ions, which come from the hot filament of the ion gun, and the initial Ba deposition layer in the YBCO film growth play the most important roles in controlling the epitaxy orientation change. Microstructure studies show that a BaxMg1-xO buffer layer is formed on top of the sputtered substrate surface due to Ba diffusion into the W implanted layer. It is believed that the formation of this buffer layer relieves the large lattice mismatch and changes the YBCO film from the 45° oriented growth to the 0° oriented growth.

The growth of coalesced, highly oriented diamond films has been achieved on nickel substrates using a multistep process that consisted of (i) seeding the Ni surface with 0.5 μm diamond powder, (ii) annealing at 1100 °C in a hydrogen atmosphere, and (iii) growth at 900 °C in a mixture of hydrogen and 0.5% methane. Auger depth profile analysis of a sample quenched after the annealing stage showed the presence of significant amounts of carbon (6 at. %) close to the substrate surface and about 3 at.% deeper in the substrate. The loss of carbon into the substrate resulted in relatively low nucleation density. The addition of methane into the gas phase during the annealing stage proved very effective in compensating for the diffusion. An addition of 0.5% methane in the gas phase produced optimum results, as the nucleation density, orientation of diamond particles, and uniformity were substantially improved. Substrates nucleated under these conditions were grown out into coalesced, 30 μm thick films. Both (100) and (111) oriented films showed a high degree of orientation and Raman spectra obtained from these orientations showed intense and narrow diamond signature peaks with FWHM's of 5 and 8 cm-1, respectively.

The detailed structure and interfacial reaction of epitaxial Yba2Cu3O7/Y-ZrO2 (YBCO/YSZ) films grown by chemical vapor deposition (CVD) on LaAlO3 (LAO) substrates are investigated by means of high-resolution electron microscopy (HREM), analytical transmission electron microscopy, and scanning transmission electron microscopy (STEM). The epitaxial relations of YBCO/YSZ/LAO are [100]YBCO // [110]YSZ // [100]LAO and (001)YBCO // (001)YSZ // (001)LAO. The optimum atomic configuration at the YSZ/LAO interface, in which oxygen is the first atomic layer on LAO, is proposed by using HREM combined with image simulation based on the atomic structure models of the interface. Near the YBCO/YSZ interface, two localized interfacial reaction products are formed: (i) a Y-rich modulated ZrO2 structure at the surface of the YSZ film, which may be caused by the diffusion of Y into the YSZ grains; (ii) an intergranular BaZrO3 phase formed by the diffusion of Ba along the columnar grain boundaries of the YSZ film during YBCO growth.

Y–Ba–Cu–O films were prepared on yttria-stabilized zirconia polycrystalline substrate using KrF excimer laser irradiation with ethylene diamine tetra-acetic acid (EDTA) complexes as a target material. The results of the x-ray θ-2θ scan showed that the films grown above 750 °C were preferentially oriented with a c-axis normal to the substrate. The value of full-width at half-maximum of (005) reflection reduced from 4.4° to 2.1° by increasing the laser power density in a range between 0.8 and 3.8 J/cm2. The transcription of the compositional ratio was improved by approaching the target-substrate distance from 45 to 20 mm. The films obtained at 800 °C consisted of many islands showing well-developed spiral growth, suggesting that the droplets of metal-EDTA complexes do not form random oriented crystalline particles on the surface of the substrate.

The solvent, supercritical antisolvent technique (SAS) has been used to produce submicronic particles of yttrium acetate for the synthesis of YBCO superconductors. For this purpose, in a continuous SAS apparatus dimethylsulfoxide (DMSO) as yttrium acetate solvent and supercritical carbon dioxide as antisolvent have been adopted. Experiments have been performed in the pressure range between 70 and 160 bar and for temperatures between 40 and 70 °C. Different concentrations of yttrium acetate in DMSO have also been tested. Various morphologies of yttrium acetate particles have been obtained, having mean particle diameters from 0.1 to 7 μm. At 40 °C and pressures larger than 120 bar, submicronic spherical particles of yttrium acetate of about 0.1 μm diameter and with a narrow particle size distribution have been achieved.

The optical properties of inorganic fullerene-like and nanotube MS2 (M = Mo, W) material are studied through absorption and resonance Raman, and compared to those of the corresponding bulk material. The absorption measurements show that the semiconductivity is preserved. Nevertheless, the positions of the excitons are altered in comparison to the bulk. The Raman spectra of the nanoparticles show a close correspondence to that of the bulk. However, the first-order peaks are broadened and, under resonance conditions, new peaks are observed. The new peaks are assigned to disorder-induced zone edge phonons.

The template-synthetic method is a general approach for preparing tubular micro-and nanostructures. This method has been used to prepare micro- and nanostructures composed of metals, carbons, semiconductors, polymers, and Li+-intercalation materials. This paper describes the use of the template method to prepare composite tubular micro- and nanostructures. These composite structures consist of an outer tubule of one material surrounding inner tubules of different materials. Chemical strategies used to prepare these composite tubular structures include electroless deposition of Au, electropolymerization of conductive and insulating polymers, electrodeposition of metals and semiconductors, carbonization of polymer precursors, chemical vapor deposition synthesis, and sol-gel synthesis.

About 15 × 106 lbs of paint sludge, produced every year at Ford plants, is disposed of in landfills. An economical alternative to this disposal method, which reclaims or recycles components of paint sludge, is highly desirable to preserve valuable natural resources. Here, we describe an alternative to landfill disposal whereby paint sludge is converted into ceramic composites that can be used as reinforcing materials. The conversion of paint sludge to ceramic composite, I/N2/600, is achieved by pyrolysis under a nitrogen atmosphere. Two additional composites, labeled I/N2/1000 and I/NH3/1000, respectively, are prepared by sintering I/600 at 1000 °C under N2 and NH3. All three composites contain crystalline CaTiO3, BaTiO3, TiO2, amorphous alumina, and carbon. I/NH3/1000 contains an additional crystalline phase of titanium nitride. The application of these composites as reinforcing materials is demonstrated in the fabrication of representative metal matrix composites (MMC's) and reinforced plastic components.

(Bi, Pb)2Sr2Ca2Cu3Ox (2223) single crystals have been grown using a fused-salt reaction of Bi2O3, PbO, SrCl2, CaCl2, CuCl, and KNO3 in a KCl flux. The pristine crystals show regular plate-like morphology with typical dimension of 0.1 × 0.1 × 0.001–0.01 mm3. Crystal orientation, chemical composition, phase purity, and superconductivity of the pristine crystals were determined by SEM, TEM, EDX, x-ray diffraction techniques, and SQUID magnetometry. The relative fraction of the Bi-2223 phase (Tc = 110 K) in as-grown crystals is ~97%. The only impurity phase, Bi-2212, occurs in some selected crystals but is present in amounts less than the detection limit of x-ray diffraction and is unobserved in the diamagnetic signal determined by SQUID magnetometry.

Polycrystalline films of cobalt oxides (Co3O4 and CoOOH) with and without Sm were fabricated on platinum substrates by electrochemical oxidation in an autoclave. The cobalt oxides were directly crystallized at temperatures higher than about 100 °C during electrolysis. The composition of the cobalt oxides strongly depended on the electrode potential; i.e., Co3O4 and CoOOH were formed in non-noble and relatively noble potential regions, respectively. When Sm was incorporated in the CoOOH by the electrolysis in solutions containing Sm3+, only the c lattice constant was increased due to an expansion in the layer structure.

To investigate the hydrogen embrittlement and Mn ductilization effects in TiAl, the electronic structures of pure, H-doped, Mn-doped, and Mn, H-codoped TiAl have been studied by the first-principles discrete variational Xa calculations. Local environmental total bond order (LTBO), which is developed for the description of the cohesive properties in a local atom environment involving impurities, should be regarded as a new microscopic criterion for embrittlement. The larger LTBO presents the stronger cohesion and the better ductility of the system. Our results show that H obviously decreases LTBO while Mn increases it, which suggests H as an embrittler while Mn as a ductilizer. It is of key importance to understand hydrogen embrittlement in which hydrogen causes the weakening of its surrounding metal-metal bonds.

Amorphous Ni50Pd40Si10 alloy powder was prepared by mechanical alloying. The surface states and catalytic activities of amorphous and crystalline Ni50Pd40Si10 alloy powder pretreated with hydrofluoric acid (HF) solution were studied. The results show that amorphous Ni-Pd-Si alloy powder was easily prepared by mechanical alloying. After treating with HF solution, the number of Pd atoms on the surface of amorphous Ni–Pd–Si powder was obviously higher than that of the crystalline alloy and catalytic activity of amorphous Ni–Pd–Si powder was higher than that of the crystalline one by three times.