In the sub-100-nm mass production of semiconductor devices, thin-film resists dispersing acid generator molecules, referred to as chemically amplified resists, have been used. Feature sizes in lithography are approaching the molecular scale with the rapid progress in miniaturization. With reductions in lateral dimensions, a decrease in resist thickness is inevitable and the effects of interfaces become significant. A requirement for ultrafine fabrication is the uniformity of resist components. In this work, the depth profile of the acid generator distribution was investigated by X-ray reflectivity measurement at SPring-8. The depth profile in thin resist films was clarified. It was found that the depth profile varies with acid generator concentration.

The crystal structure of superconducting Na(2)CsC(60) was studied by high-resolution powder neutron diffraction between 1.6 and 425 K. Contrary to the literature, the structure at low temperatures is primitive cubic [See equation in the PDF file], isostructural with pristine C(60). Anticlockwise rotation of the C(60) units by 98 degrees about [111] allows simultaneous optimization of C(60)-C(60) and alkali-fulleride interactions. Optimal Na(+)-C(60)(3-) coordination is achieved with each sodium ion located above one hexagon face and three hexagon-hexagon fusions of neighboring fulleride ions (coordination number 12). Reduction of the C(60) molecule lengthens the hexagon-hexagon fusions and shortens the pentagon-hexagon fusions (to approximately 1.43 angstroms). On heating, Na(2)CsC(60) undergoes a phase transition to a face-centered-cubic [See equation in the PDF file] phase, best modeled as containing quasi-spherical C(60)(3-) ions. The modified structure and intermolecular potential provide an additional dimension to the behavior of superconducting fullerides and should sensitively affect their electronic and conducting properties.

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Reflection ellipsometry is applied to characterize the molecular orientation of rubbed polyimide films for liquid crystal display devices. Thickness, dielectric constants and tilt angle of the principal dielectric axis of the molecularly oriented upper layer and thickness of the random layer in rubbed polyimide films can be determined by analyzing the anisotropic polarization of reflected light.

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