The effect of pad surface texture on dielectric and copper removal rates was studied theoretically and experimentally by investigating the fluid behavior of the slurry layer using methodologies similar to those found in tribological investigations of fluid bearings. It is shown that new nonfoamed hard plastic pads with intricate groove patterns are critical in modulating removal rates. Removal rate results of dielectric chemical mechanical polishing were in close agreement with model predictions for several of the groove designs tested. Combined patterns, consisting of spiral and logarithmic grooves, were shown to impact several key attributes of the dielectric and copper processes in terms of slurry retention, hydrodynamic pressure, tribological mechanism, and material removal rates.
Spatial distribution of bromobenzene (BrBz) and 4-bromophenol (BrPh) as hydrophobic aromatic compounds incorporated in polymer micelles with vesicular structure consisting of poly(ethylene glycol)-b-poly(tert-butyl methacrylate) (PEG-b-PtBMA) in aqueous solution is investigated by anomalous small-angle X-ray scattering (ASAXS) analyses near Br K edge. Small-angle X-ray scattering (SAXS) intensities from PEG-b-PtBMA micelles containing BrBz and BrPh were decreased as the energy of incident X-ray approached to Br K edge corresponding to the energy dependence of anomalous scattering factor of Br. The analysis for the energy dependence of SAXS profiles from the PEG-b-PtBMA micelles containing BrBz revealed that BrBz molecules were located in hydrophobic layer of PEG-b-PtBMA micelles. On the contrary, it was found by ASAXS that BrPh existed not only in the hydrophobic layer but also in the shell layer. Since ASAXS analysis successfully accomplished to visualize the spatial distribution of hydrophobic molecules in polymer micelles, it should be expected to be a powerful tool for characterization of drug delivery vehicles.
We have developed a new conceptual LCD with a memory circuit and a photo-sensor in each pixel. This LCD enables to display a still image in the low power consumption. In addition, direct writing and erasing a character in the LCD are available without calculating coordinates by using a light pen.
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