The temperature dependence of the various electric relaxation times in the perovskite oxide CaCu3Ti4O12 (CCTO) is determined (i) by trap state spectroscopy and (ii) by the dielectric loss function. A similarity in both number and properties of the (i) and (ii) relaxation times was found, suggesting that the dielectric response is strongly correlated with the trap state relaxation, although some differences remain. One or more dipoles developing charged trap states are considered responsible, and the experimental dielectric response of CCTO and Mn substituted CCTO are explored.

High-pressure in situ angular dispersive x-ray diffraction study on the wurtzite-type InN nanowires has been carried out by means of the image-plate technique and diamond-anvil cell (DAC) up to about 31.8 GPa. The pressure-induced structural transition from the wurtzite to a rocksalt-type phase occurs at about 14.6 GPa, which is slightly higher than the transition pressure of InN bulk materials (∼12.1 GPa). The relative volume reduction at the transition point is close to 17.88%, and the bulk modulus B0 is determined through fitting the relative volume-pressure experimental data related to the wurtzite and rocksalt phases to the Birch–Murnaghan equation of states. Moreover, high-pressure Raman scattering for InN nanowires were also investigated in DAC at room temperature. The corresponding structural transition was confirmed by assignment of phonon modes. We calculated the mode Grüneisen parameters for the wurtzite and rocksalt phases of InN nanowires.

The deposition of amorphous InGaZnO4 (a-IGZO) semiconductor film, via a sputtering process, has been demonstrated in the literature. In this paper, we present a solution method as an alternative to obtain this semiconducting film. The dispersible IGZO colloids is formed first by co-precipitation of precursors, followed by hydrothermal treatment at 200°C for 1 hour and using CMC as the dispersion agent. The crystalline colloid would become amorphous when it was heated at above 250°C. The TFT structure was made by growing a dielectric silica layer using the CVD method, a metal layer using the sputtering method, and an active IGZO layer using the solution method. This device exhibits low operating voltage, the mobility is about 2cm2V−1s−1 and the Ion/Ioff ratio is 104. Further improvement in processing is needed.

We present proof-of-concept experiments for developing a highly-sensitive and fast-response miniaturized single-walled carbon nanotube field-effect transistor (SWNT-FET) biosensor for electrically detecting adenovirus using ligand-receptor-protein specificity. SWNTs are mildly oxidized to form carboxylic groups on the surfaces without compromising the electronic integrity of the nanotubes. Then the human coxsackievirus and adenovirus receptor (CAR) is covalently functionalized onto the nanotube surface via diimide-activated amidation process. Upon exposure of the device to adenovirus protein, Ad12 Knob (Knob), specific binding of Knob to CAR decreases the current that flows through the SWNT-FET device. For control experiment, the CAR-SWNT device is exposed to YieF, which is a virus protein that does not bind specifically to CAR, and no current change is observed. The biological activity of the CAR and Knob proteins that are immobilized on SWNTs has been confirmed by previous fluorescence studies [1]. AFM analysis is done to show height increase of a few nanometers at specific spots where the CAR-Knob complex are covalently linked to the nanotube surface. Therefore, our results show that the human receptor protein CAR does immobilize on SWNT surface while fully retains its biological activity. Moreover, the specific binding of CAR to its complementary adenovirus Knob can be electrically detected using individual SWNT-FET devices. These findings suggest that CAR-functionalized SWNT-FETs can ably serve as biosensors for detection of environmental adenoviruses.

Nickel has been widely used as an under-bump metallization (UBM) material in the microelectronics industry. The solid-state reaction between the eutectic SnAg solder bumps and three thicknesses of Ni/Cu UBM was investigated, with 5 μm-Cu/3 μm-Ni, 3 μm-Cu/2 μm-Ni, and 0 μm-Cu/1 μm-Ni. It was found that the shear strength of the solder bumps decreased after the solid-state aging at 150 °C for 200 h, and it did not change much after it was prolonged for 500 and 1000 h. Aging of the Ag3Sn intermetallic compound (IMC) and grain growth of the solder are responsible for the decrease in the shear strength. Furthermore, the shear test results indicated that the fracture mode switched from ductile to brittle for the solder bumps with 1 μm Ni after aging longer than 200 h, causing the strength of the solder to decrease abruptly. This is attributed to the consumption of the peripheral Ni layer after the solid-state aging for 1000 h. The Ni consumption rate was measured to be 0.02 μm/h1/2 at 150 °C.

Transmission and scanning electron microscopy, Rutherford backscattering-channeling and Read camera glancing angle x-ray diffraction techniques have been applied to study the epitaxial growth of nickel and cobalt germanides on germanium.

NiGe, Co5Ge7 and CoGe2 were found to grow epitaxially on both (001) and (111)Ge. More extensive epitaxy on (111)Ge is correlated with better lattice matches at the germanide/Ge interfaces than those on (001)Ge for these epitaxial germanides.