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An investigation on monolayers of alkyl chains, attached through direct Si-C bonds to Si(111), through phosphonates to GaAs(100) surfaces, or deposited as alkyl-silane monolayers on SiO2 is conducted by ultraviolet and inverse photoemission spectroscopy and X-ray absorption spectroscopy. Exposure to ultraviolet radiation from a He discharge lamp, or to a beam of energetic electrons, leads to significant damage, presumably associated with radiation- or electron-induced H-abstraction leading to carbon-carbon double-bond formation in the alkyl monolayer.

Angle-resolved photoelectron spectroscopy (ARUPS) is used to study the electronic structure and supramolecular organization of the discotic molecule deposited on graphite. The study reveals the strongly delocalized nature of the pi-electrons along the discotic stacks.

Direct photomicromachining in poly(vinylidene fluoride) is studied.

In-(perylene-3,4,9,10-tetracarboxylic dianhydride) (PTCDA), an organic semiconductor, was measured using angle-resolved ultraviolet photoelectron spectroscopy with synchrotron radiation, to observe the origin of the band gap state.

Research was conducted to examine the angle-resolved ultraviolet photoelectron spectra of copper phthalocyanine and metal-free phthalocyanine films on cleaved MoS2 substrates by means of monochromatic synchrotron radiation. Single-scattering approximation theory combined with molecular orbital measurements was used to analyze take-off angle and azimuthal angle dependencies of the top pi band intensity. Results indicate that there are only molecules with counterclockwise motion although both clockwise and counterclockwise rotations were expected.

A study was conducted to examine the degradation of poly(methyl methacrylate) thin films using vacuum ultraviolet monochromatic synchroton radiation. The valence band structure was simulated for the nondegraded thin films while photoelectron spectra was determined by a plane grating monochromator beamline. Results indicated that degradation products supported a rich conjugation of unsaturated bonds.

Low-energy electron microscopy (LEEM) and metastable electron emission microscopy (MEEM) were used to study images and local electron spectra of an oxide pattern on Si(100) in which energy-filtered images were seen for the first time. Results of the study revealed that LEEM provides averaged information on several surface layers while MEEL gives the information on the outermost surface layer selectively. Other observations are discussed.

A simple alternative was studied for the tri-layer resist system. One single thick layer of resist polymer was surface silylated to obtain a bilevel structure that functioned similarly to the bilayer resist composed of the Si-containing top imaging and the bottom planalizing layers. A resist or matrix polymer layer containing phenolic -OH groups was silylated by exposing it to hexamethyldisilazane vapor, and Si atoms were effectively incorporated in the surface sublayer by limited gas permeation and reaction with the -OH groups. Oxygen RIE durability of the silylated poly(vinyl phenol) or the positive-working commercial EB resist, RE-5000P, was > 10 times as high as that of PVP or RE-5000P before silylation. The surface silylated single-layer (SSS) resist derived from RE-5000P was flood-exposed through a mesh mask to 11.7 micro-C/cm squared of 4 KeV electrons, developed with tetramethylammonium hydroxide in aqueous methanol, and plasma-developed in an O(sub 2) RIE chamber to form a positive-tone relief image.

The regularly appearing features in low-energy-electron transmission (LEET) spectra at room temperature (RT) are found for monolayers of various organic-semiconductor molecules on MoS2 and graphite surfaces. The results propose that the injected excess electron traveling across the monolayer is affected by the substrate-molecule interaction.

The result of low energy electron diffraction (LEED) are measured and showed that an ordered In-PTCDA (perylene-3, 4,9,10-tetracarboxylic dianhydried) system can be formed on MoS2 surface by annealing. The LEED analysis shows that the In-PTCDA species lie titled on the MoS2 surface.

A study was conducted, by using the ultraviolet photoelectric spectroscopy, to examine the electronic structure of poly-(1,1,2,2-tetramethyldisilylenemethylene), [(SiMe(sub 2))(sub 2)CH(sub 2)](sub n), which consists of repeating Si-Si-C units. The broad peak derived from Si-Si bond orbitals in polycarbosilane suggests that Si-Si units still interact with each other, to form sigma-conjugation through the backbone.