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The structural evolution during heteroepitaxial growth of ZnO/sapphire(001) by radio-frequency magnetron sputtering has been studied using real-time synchrotron x-ray scattering. The two-dimensional (2D) ZnO(002) layers grown in the initial stage are highly strained and well aligned to the substrate having a mosaic distribution of 0.01° full width at half maximum (FWHM), in sharp contrast to the reported transition 2D layers grown by molecular-beam epitaxy. With increasing film thickness, the lattice strain is relieved and the poorly aligned (1.25° FWHM) three-dimensional (3D) islands are nucleated on the 2D layers. We attribute the 2D–3D transition to the release of the strain energy stored in the film due to the film/substrate lattice mismatch.

Charge trapping induced by hot carriers in a metal–oxide–semiconductor capacitor was studied with a scanning capacitance microscope (SCM). The local charge trapping/detrapping and the readout of the trapped charge in SiO2 was performed using a SCM combined with an atomic force microscope. When applying a voltage between the conductive probe tip and the p-type silicon substrate, hot carriers injected from silicon substrate into the SiO2 generated a positive trapped charge in the 10-nm-thick SiO2 layer. The resulting shift in capacitance–voltage (C–V) curves due to the locally trapped charge was measured by the high-frequency C–V measurement. For an application to the ultrahigh density data storage field, we investigated how the charge trapping and detrapping characteristics depend on the writing speed and bias voltage.

We have developed a simple tapping mode in atomic force microscopy using a capacitive electrostatic force. In this technique, the probe‐to‐sample distance is modulated by the capacitive force between tip and sample induced by a sinusoidal bias applied to the conductive probe instead of a conventional mechanical vibration. The electrostatic force versus distance curve of the probe indicates that it is necessary to use a rather stiff cantilever to prevent the snapping of the tip into the surface due to the adhesive force at the surface. We have succeeded in obtaining topographic images of a conductive surface as well as a soft polystyrene sample with a low tracking and lateral force through this method.

A thermally evaporated molybdenum oxide (MoO3) film was used as a window layer of a hydrogenated amorphous silicon (a-Si:H) solar cell instead of the conventional p-type hydrogenated amorphous silicon carbide (p-a-SiC:H) film. The short circuit current density (JSC) and fill factor were increased due to the wide optical band gap and high conductivity of the MoO3 film. As a result, the conversion efficiency of the fabricated MoO3 solar cell was increased to 6.21% compared to the typical a-Si:H solar cell (5.97%).

This letter presents approaches for assembly and electrical interconnection of micro/nanoscale devices into functional systems with useful characteristics. Transfer printing techniques provide deterministic control over an assembly process that occurs prior to or simultaneously with a soft lithographic molding step that defines relief features in a receiving polymer. Filling these features with conducting materials that are processable in the form of liquids or pastes yields integrated interconnects and contacts aligned to the devices. Studies of the underlying aspects and application to representative systems in photovoltaics and solid state lighting indicators provide insights into the process and its practical use.

Tilt boundaries have been observed on the (0001) surface of graphite by scanning tunneling microscopy (STM). Rotation angles about the c axis of 6.5°, 8°, and 19° were found, indicating no preferential orientation of grains in the basal plane of graphite. The grain boundary region between crystallites appears disordered with a width varying between 10 and 100 A. Moire patterns are observed near grain boundaries when multiple tips scanning over different grains contribute to the image simultaneously. Such images support the theory that multiple isolated tips, occasionally hundreds of angstroms apart, can contribute to STM images.

Images of graphite have been recorded with a scanning tunneling microscope operating in air at ambient pressure. The results, which are in agreement with theory and previous experiments in vacuum, confirm that with a surface such as graphite the tunneling microscopy in air can be used to examine the geometry of the surface with a resolution that is less than 2 A.

The behavior of gallium on the Si(100) surface has been studied with scanning tunneling microscopy at low metal coverages. The Ga atoms are more mobile on Si(100) than on Si(111) under the same conditions. At less than 0.1 monolayer, the Ga atoms line up in rows parallel to the Si dimerization direction with a two unit cell periodicity. At higher metal densities, these rows are organized into areas of 3×2 two‐dimensional order. The relevance of these results to studies of the initial stages of growth of GaAs on Si is discussed.