Dean Eric Eastman

High resolution photoelectron studies: Electric field gradient splittings of Cd and Sn 4d energy levels in organometallic compounds

Abstract High resolution photoelectron spectra of Me2Cd (Me = CH3) in the gas phase, and organotin compounds in the solid state show that the 4d9 final state produced in the photoelectron experiment splits in the presence of ligand fields. Only the C20 crystal field term (the term that transforms like the electric field gradient) contributes to the splitting. The 4d 3 2 splitting in Me2Cd and trans-Me2Sn(BzBz)2 (BzBz = anion of dibenzoylmethane) are 0.21 ± 0.01 eV and 0.35 ± 0.1 eV respectively. The observed 4d 5 2 linewidth for Ph4Sn (Ph = C6H5) of 0.67 eV indicates that very narrow linewidths can be obtained on molecular nonconducting solids. The constant spin-orbit splitting values, combined with nuclear field gradients from Mossbauer and NQR measurements, strongly indicate that a previously proposed explanation for the increase in apparent spin-orbit coupling in Cd metal is untenable.

Hot electron scattering and optical density of states of yttrium

Abstract The mean free path of hot electrons in Y has been determined as ∼ 10A at 7 eV above ther Fermi level EF using a new photoemission method. The importance of this strong electron≅electron scattering in photoemission spectroscopy work is shown via an analysis of the optical density of states of Y. We find an occupied d-band with a peak at EF and a width of 1.6 ± 0.2 eV (at 1 2 maximum).

Future Beam-Controlled Processing Technologies for Microelectronics

Beam-controlled processes that utilize photons, electrons, ions, and molecules have become essential in the fabrication of microelectronics. These processes are required for the deposition, patterning, etching, and characterization of semiconductor, packaging, and processing-related materials that form the basis of the integrated circuit. Fabrication techniques demand an increasing precision as the physical size of the device structures shrink to submicrometer dimensions. In this article, selected examples of beam-controlled processes expected to be important in the microelectronics industry are described. The continued rapid advances in microelectronics technology that underlie the electronic information-processing industry require the continued development and refinement of these new techniques.

Interpretation of the photoelectron spectra of molecularly adsorbed CO

Abstract We have measured the photoemission spectra both for CO adsorbed on Ni and Pd films and for gas phase CO over a wide photon energy range. The comparison of these two sets of measurements lead to the following interpretation of the two observed electronic energy levels of molecularly adsorbed CO. The lower binding energy CO-induced level corresponds to the 1π gas phase level with some admixture of the 5σ level and the higher binding energy level corresponds to the 4σ gas phase level. The h ω-dependence of the photoionization cross section is shown to play a predominant role in determining the surface sensitivity.