Miniaturized triblock copolymers have been found to self-assemble into nanostructures that are highly regular in size and shape. Mushroom-shaped supramolecular structures of about 200 kilodaltons form by crystallization of the chemically identical blocks and self-organize into films containing 100 or more layers stacked in a polar arrangement. The polar supramolecular material exhibits spontaneous second-harmonic generation from infrared to green photons and has an adhesive tape-like character with nonadhesive-hydrophobic and hydrophilic-sticky opposite surfaces. The films also have reasonable shear strength and adhere tenaciously to glass surfaces on one side only. The regular and finite size of the supramolecular units is believed to be mediated by repulsive forces among some of the segments in the triblock molecules. A large diversity of multifunctional materials could be formed from regular supramolecular units weighing hundreds of kilodaltons.

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A diacetylene monomer with a rigid backbone and capable of forming hydrogen bonds was synthesized and found to polymerize forming two-dimensional supramolecular assemblies. The twodimensional structure self-assembles when UV light generates polydiacetylene comb polymers, and hydrogen bonds are established within molecular layers. The two-dimensional assemblies have been characterized by X-ray diffraction and infrared spectroscopy and found to consist of highly ordered bilayers. The material forms blue solid thin films which generate third-order nonlinear optical signals and have remarkable photochemical stability to 1064 nm radiation from a Q-switched Nd:YAG laser. Upon heating to 62 °C, the material turns bright red reversibly while maintaining its two-dimensional structure, and this thermochromic process is accompanied by endothermic and exothermic signatures detected by differential scanning calorimetry. Most importantly, however, variable temperature sum frequency generation experiments show that the third-harmonic generation signals retain much of their original intensity through the thermochromic transitions. These results do not conform in a consistent manner to both the theory of third-order effects and the previously suggested connection between intramolecular conjugation and optical absorption of polydiacetylenes. It is therefore possible that intermolecular interactions in these highly ordered structures play a role in defining optical properties.

The OPE signature of a lithographic stepper or scanner has become a very important characteristic of the tool, as it determines the OPC correction to be applied to reticles exposed on that tool. The signature depends on a variety of detailed information about the scanner lens and illuminator, which in turn depend on the characteristics of the illumination light from the laser.Specifically, changes in the laser bandwidth should impact OPE as the lens exhibits some chromatic aberration. Tool-totool differences and time fluctuation of the laser bandwidth could cause variations in OPE tool matching and stability.To assess this, a detailed study of laser bandwidth effects on OPE was performed. A sensitive spectrometer was connected to a litho laser, allowing careful measurements of both the FWHM and E 95 parameters of the laser spectral profile.Lithographic modeling using the chromatic response of the lens was run in order to predict effects. Exposures of CD through pitch were made to test the modeling. Finally, the bandwidth data was correlated with litho sensitivity to create a "bandwidth effect", put in context with the other common scanner parameters affecting OPE.

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