The technique used to align liquid crystals-rubbing the surface of a substrate on which a liquid crystal is subsequently deposited-has been perfected by the multibillion-dollar liquid-crystal display industry. However, it is widely recognized that a non-contact alignment technique would be highly desirable for future generations of large, high-resolution liquid-crystal displays. A number of alternative alignment techniques have been reported, but none of these have so far been implemented in large-scale manufacturing. Here, we report a non-contact alignment process, which uses low-energy ion beams impinging at a glancing angle on amorphous inorganic films, such as diamond-like carbon. Using this approach, we have produced both laptop and desktop displays in pilot-line manufacturing, and found that displays of higher quality and reliability could be made at a lower cost than the rubbing technique. The mechanism of alignment is explained by adopting a random network model of atomic arrangement in the inorganic films. Order is induced by exposure to an ion beam because unfavourably oriented rings of atoms are selectively destroyed. The planes of the remaining rings are predominantly parallel to the direction of the ion beam.

Excitation spectra of the alkali-metal stage-1 intercalated graphites KCS, RbCS, and CsC8 have been measured by high-resolution (0.1 eV) electron-energy -loss spectroscopy. The m intraband and interband plasmon excitations in the region below 10 eV are the same in aB three compounds. However, in the valence region between 15 and 30 eV, small peaks are observed in RbC8 and CsC8 which are weaker than those previously observed in KC8. In KC8, these structures were identified as both excitations to the backfolded graphite bands created by the introduction of the intercalant and also as characteristic metal-atom core excitations. Within this interpretation, the weakening of the structure due to the backfolded bands with intercalant atomic number is consistent with weakening the coupling far above the Fermi level between the graphite and intercalant atoms. The carbon 1s core shell excitation at -285 eV is also reported. %'e find that both the spectral shape and threshold energy are unaffected by the choice of alkali-metal intercalant (K, Rb, Cs), although the resulting spectrum differs from that of pristine graphite. Hence the graphite p states just above the Fermi level which are probed by the C 1s excitation are identically perturbed by the K, Rb, and Cs intercalations, suggesting that the degree of hybridization and charge transfer in these materials is the same.Intercalation of graphite with alkali metal to stage 1 yields a model layer compound in which the alternating metal and graphite atom planes interact, resulting in a compound exhibiting electronic properties different than those of pristine graphite. In particular, we expect the alkali-metal atoms to at least partially donate their weakly bound outermost s electron to the graphite planes. Such charge transfer shifts the Fermi level (FF} up from its value before intercalation, changing the nature of the highest occupied states. Also, since the alkali-metal valence s states are degenerate in energy with the graphite m bands, and since the metal-carbon (M-C} interatomic distances are quite small, we may expect to observe hybridization between the metal and the graphite orbitals. Electron-energy -loss spectroscopy (EELS) has been shown to be a sensitive probe of the electronic properties of intercalated graphite. ' By performing a KramersKronig analysis on the loss data, the real and imaginary parts of the dielectric function may be obtained, and the elementary excitation spectrum of the solid determined. This paper contributes to a growing body of literature and consists of a comparative study at high-energy resolution and statistics of the three alkali-metal graphite intercalated compounds (GIC's) which form an MCs stage-1 structure, KC8, RbCS and CSCS. In the valence portion of the spectrum, we observe features unresolved by previous measurements taken at poorer resolution and statistics. We shall find that those excitations involving states close to the Fermi level are virtually indistinguishable in KC8 versus RbCS versus CsC8, providing strong evidence that...

This paper addresses some of the problems encountered in propagating high-speed signals on lossy transmission lines encountered in highperformance computers. A technique is described for including frequency-dependent losses, such as skin effect and dielectric dispersion, in transmission line analyses. The disjoint group of available tools is brought together, and their relevance to the propagation of high-speed pulses in digital circuit applications is explained. Guidelines are given for different interconnection technologies to indicate where the onset of severe dispersion takes place. Experimental structures have been built and tested, and this paper reports on their electrical performance and demonstrates the agreement between measured data and waveforms derived from analysis. The paper

The lowering of the Fermi energy in stage-1 FeCl 3 -intercalated graphite is directly measured in the spectrum of electronic excitations from carbon Is core states to empty carbon 2p states which appear after intercalation. The shape of the core exciton spectrum is related to the initial distribution of empty states in a formulation of the core exciton problem which includes the effect of electronic relaxation near the core hole.A background continuum in the Raman spectrum of adsorbed molecules at a silverelectrolyte interface is observed experimentally. This background continuum is potential dependent on the Stokes and anti-Strokes of the spectrum and fits a Fermi distribution function on the anti-Stokes side of the spectrum. The continuum is interpreted in terms of radiative recombination of adsorbed molecular ions produced by photo ionization.

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