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Articles you may be interested inAdsorption and reaction of acetylene on clean and oxygen-precovered Pd(100) studied with high-resolution X-ray photoelectron spectroscopy Ethene adsorption and dehydrogenation on clean and oxygen precovered Ni(111) studied by high resolution xray photoelectron spectroscopy J. Chem. Phys. 133, 014706 (2010); 10.1063/1.3456732 N H 3 adsorption and decomposition on Ir(110): A combined temperature programmed desorption and high resolution fast x-ray photoelectron spectroscopy study Oxygen adsorption on Ag(111): X-ray photoelectron spectroscopy (XPS), angular dependent x-ray photoelectron spectroscopy (ADXPS) and temperature-programmed desorption (TPD) studies Using synchrotron radiation, the adsorption and decomposition of propene (C 3 H 6 ) on the Ni͑100͒ surface has been investigated in situ by time-resolved and temperature-programmed x-ray photoelectron spectroscopy. At 105 K, high-resolution C 1s spectra indicate precursor mediated occupation of a single adsorption state from submonolayer to monolayer coverage with evidence of adsorbate-adsorbate interactions and dispersed phase growth. High exposures lead to the formation of multilayers which desorb above 105 K leaving a chemisorbed monolayer. Between 105 and 150 K, a shift of the binding energies in the C 1s spectra is attributed to the transition fromto di--bonded propene. An abrupt change in the photoemission spectra occurs at 200 K due to the conversion of di--bonded propene to a C 3 intermediate containing a methyl group. Formation of this C 2 H x CH 3 surface species is complete at 300 K and is immediately proceeded by dehydrogenation to carbidic carbon which is the final decomposition product above 370 K.

Temperature-programmed x-ray photoelectron spectroscopy was used to study the thermal chemistry of acetylene (C2H2) and ethylene (C2H4) on Ni(100) in the temperature range 90–530 K. The use of a third generation synchrotron light source facilitated the measurement of high-resolution C 1s photoelectron spectra within a few seconds, approaching the ideal of real-time analysis. In a quantitative and quasi-continuous manner, the thermal dehydrogenation pathways are followed. For the acetylene decomposition, acetylide (CCH) and methylidyne (CH) are confirmed as intermediates. For the dehydrogenation of ethylene, a vinyl species (C2H3) is observed. Using the fingerprint capabilities of x-ray photoelectron spectroscopy, acetylene can be identified as the subsequent dehydrogenation product. Upon further heating, acetylide and methylidyne are successively formed on the surface, as in the decomposition experiment starting with acetylene adsorbed at 100 K. For both systems carbidic carbon is formed as the final dehydrogenation product, although with different transition temperatures. Species identification is based on observed vibrational fine structure data and correlation of core-level binding energies with previous literature.

Chromeless Phase Lithography (CPL) is discussed as interesting option for the 65nm node and beyond offering high resolution and small Mask Error Enhancement Factor. However, it was shown recently that at high NA CPL masks can exhibit large polarization and also phase effects. A well known phase effect occurring for CPL semi dense lines are through focus Bossung tilts. However, another manifestation of phase effects for dense lines and spaces is a reduced contrast for a symmetrical offaxis illumination due to phase errors between 0 th and 1 st diffraction order. In this paper it is shown that these phase effects can lead to a significant contrast loss for dense features smaller than 60nm half pitch. While also present for trench structures, the contrast reduction is more pronounced for mesa style structures. It is shown that for mesa structures an adjustment of etch depth can not recover an effective pi-phase shift. Furthermore, significant polarization effects are observed. As an example, the optimum mesa structure for TE polarization is shifted to small lines. For an experimental validation, a CPL mask containing dense lines and spaces was fabricated. Their imaging performance was characterized with an AIMS 45i offering NA's greater than 1 and linearly polarized illumination as well as by wafer printing. Gratings with pitches down to 100 nm with varying duty cycles were measured with TE, TM and unpolarized dipole illumination. Very good agreement between measurement and simulation results confirmed the validity of theoretical predictions.

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