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Matrix-isolation infrared spectra of trimethyl phosphate (TMP), triethyl phosphate (TEP), and tri- n-butyl phosphate (TBP), in argon and nitrogen matrices, are reported for the first time. The peak widths of the sharpest features in our matrix-isolated spectra are typically 2 cm−1, compared with peak widths of 40 cm−1 seen in liquids for these compounds. Comparison with the vapor-phase spectrum of TMP reported earlier indicates that TMP is trapped in two different conformations in these matrices. Similar spectra were also obtained for TEP. Our matrix-isolated spectra indicate that the intramolecular hydrogen bonding (which is believed to be responsible for the lowering of the P=O frequency in the C3, conformer relative to the C3 conformer in these compounds) is stronger in TEP than in TMP. In the case of TBP, the peak widths were larger (8–10 cm−1) than those obtained for TMP and TEP. This observation is probably due to a distribution of conformers that may be trapped in the matrix, as a result of the increased alkyl chain length in TBP.

New method of calculating adsorption and scattering for Xe-Pt (111) using Direct Simulation Monte Carlo techniques J. Vac. Sci. Technol. A 30, 061401 (2012) Current-voltage-time characteristics of the reactive Ar/O2 high power impulse magnetron sputtering discharge J. Vac. Sci. Technol. A 30, 050601 (2012) Influence of magnetic ordering on the elastic properties of PdFe3N J. Vac. Sci. Technol. A 30, 030602 (2012) Investigation of the factors determining the SIMS depth resolution in silicon-isotope multiple layers J. Vac. Sci. Technol. B 30, 011803 (2012)Hydrogen effects in hydrofluorocarbon plasma etching of silicon nitride: Beam study with CF+, CF2+, CHF2+, and CH2F+ ions There is a growing interest in knowing the sputter rates for a wide variety of oxides because of their increasing technological importance in many different applications. To support the needs of users of the Environmental Molecular Sciences Laboratory, a national scientific user facility, as well as our research programs, the authors made a series of measurements of the sputter rates from oxide films that have been grown by oxygen plasma-assisted molecular beam epitaxy, pulsed laser deposition, atomic layer deposition, electrochemical oxidation, or sputter deposition. The sputter rates for these oxide films were determined in comparison with those from thermally grown SiO 2 , a common reference material for sputter rate determination. The film thicknesses and densities for most of these oxide films were measured using x-ray reflectivity. These oxide films were mounted in an x-ray photoelectron or Auger electron spectrometer for sputter rate measurements using argon ion sputtering. Although the primary objective of this work was to determine relative sputter rates at a fixed angle, the measurements also examined ͑i͒ the angle dependence of the relative sputter rates, ͑ii͒ the energy dependence of the relative sputter rates, and ͑iii͒ the extent of ion beam induced reduction for some oxides. Oxide films examined include SiO 2 O 5 , TiO 2 ͑anatase, rutile, and amorphous͒, and ZnO. The authors found that the sputter rates for the oxides can vary up to a factor of 2 ͑usually lower͒ from that observed for SiO 2 . The ratios of sputter rates relative to those of SiO 2 appear to be relatively independent of ion beam energy in the range of 1-4 kV and for incident angles Ͻ50°. As expected, the extent of ion beam induced reduction of the oxides varies with the sputter angle.

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