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Increasing complexity and manufacturing costs, along with the fundamental limits of planar CMOS devices, threaten to slow down the historical pace of progress in the semiconductor industry. We have proposed and demonstrated proof-of-concept of a simple and low-cost way to fabricate dual-damascene copper (Cu) on-chip interconnect or Back-End-Of-the- Line (BEOL) structures using a novel multifunctional on-chip electrical insulator called a photo-patternable low dielectric constant (low-) dielectric (PPLK) material [Q. Lin, et al, Proc. SPIE,2010]. This demonstration was accomplished with a silsesquioxane-based (SiCOH), =2.7 material which is compatible with 248 nm optical lithography. In this paper, we report on the extension of the photo-patternable low- concept to the ultra-low- (<2.5) regime and resolution down well below 100 nm with 193 nm lithography as well as e-beam lithography. We have accomplished this demonstration using the same silsesquioxane-based (SiCOH) material platform as that of the 248 nm photo-patternable low- materials. The 193 nm photo-patternable low- materials possess dielectric constants below 2.5 and are able to resolve 100 nm half-pith line/space features with dry 193 nm single exposure lithography. The resolution of photopatternable low- materials can be pushed down to 40 nm half-pith line and space features with a line-edge-roughness less than 3.0 nm with e-beam lithography.

A framework is introduced for fault diagnosis in timed discrete-event systems. In this approach, the required estimates for system condition are updated only when the output changes or when deadlines associated with output changes expire. Thus updates at every clock tick are not required. This in many cases results in reduction in online computing requirements and in the size of the diagnosis system, at the expense of more offline design calculations. The issue of failure diagnosability is also discussed. [ABSTRACT FROM AUTHOR]

Monodisperse poly(4- and poly(2-vinylpyridine) nanospheres in the 500 nm diameter range were prepared by emulsifier-free emulsion polymerization techniques under free radical initiation of the respective monomers with 4 wt % divinylbenzene as the cross-linking agent. The size, integrity, and nature of the nanospheres were investigated by Scanning electron microscopy, transmission electron microscopy, energy-dispersive X-ray analysis, Auger spectroscopy, and Fourier-transform infrared spectroscopy measurements. The rigid and highly stable nanospheres with exposed pyridine nitrogen on the surface serve as an excellent support for Pd⁰ nanoparticles in the range of 1−4 nm. The Pd-coated nanospheres were also characterized by transmission electron microscopy and inductively coupled plasma mass spectrometry measurements. Four weight percent palladium-coated nanospheres serve as good catalysts for Suzuki-, Heck-, and Stille-type coupling reactions for carbon−carbon bond formation.

Two new platinum(II) porphyrins have been synthesized and their luminescent properties have been studied. The platinum porphyrins exhibited strong phosphorescence in the red with narrow line widths. When they were doped into aluminum(III) tris(8-hydroxyquinolate) (AlQ3) in the electron-transporting and -emitting layer of an organic light-emitting device, energy transfer occurred between the host AlQ3 and the platinum porphyrin. Bright saturated red emission with high efficiency at low to moderate current density has been achieved. In the high current regime, the electroluminescence efficiency decreased and the perceived emission color blue shifted as a result of mixed emission from the platinum porphyrin and AlQ3. This current dependence was due to the saturation of triplet emissive sites, because of the long-lived phosphorescence state of the platinum porphyrin complex.

We constructed a bacteriophage-displayed library containing randomized mutations at H chain residues 30-35 of the anti-digoxin antibody 26-10 Fab to investigate sequence constraints necessary for high affinity binding in an antibody of known crystal structure. Phage were selected by panning against digoxin and three C-16-substituted analogues. All antigen-positive mutants selected using other analogues also bound digoxin. Among 73 antigen-positive clones, 26 different nucleotide sequences were found. The majority of Fabs had high affinity for digoxin (Ka 3.4 x 10(9) M-1) despite wide sequence diversity. Two mutants displayed affinities 2- and 4-fold higher than the parental antibody. Analysis of the statistical distribution of sequences showed that highest affinity binding occurred with a restricted set of amino acid substitutions at positions H33-35. All clones save two retained the parental Asn-H35, which contacts hapten and hydrogen bonds to other binding site residues in the parental structure. Positions H30-32 display remarkable diversity, with 10-14 different substitutions for each residue, consistent with high affinity binding. Thus complementarity can be retained and even improved despite diversity in the conformation of the N-terminal portion of the H-CDR1 loop.