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The uncontrolled development of nanoscale roughness during plasma exposure of polymer surfaces is a major issue in the field of semiconductor processing. In this paper, we investigated the question of a possible relationship between the formation of nanoscale roughening and the simultaneous introduction of a nanometer-thick, densified surface layer that is formed on polymers due to plasma damage. Polystyrene films were exposed to an Ar discharge in an inductively coupled plasma reactor with controllable substrate bias and the properties of the modified surface layer were changed by varying the maximum Ar+ ion energy. The modified layer thickness, chemical, and mechanical properties were obtained using real-time in situ ellipsometry, x-ray photoelectron spectroscopy, and modeled using molecular dynamics simulation. The surface roughness after plasma exposure was measured using atomic force microscopy, yielding the equilibrium dominant wavelength λ and amplitude A of surface roughness. The comparison of measured surface roughness wavelength and amplitude data with values of λ and A predicted from elastic buckling theory utilizing the measured properties of the densified surface layer showed excellent agreement both above and below the glass transition temperature of polystyrene. This agreement strongly supports a buckling mechanism of surface roughness formation. [ABSTRACT FROM AUTHOR]

Chalcogenide glasses have attracted considerable attention and found various applications due to their infrared transparency and other optical properties. The As–S–Se chalcogenide glass, with its large glass-formation domain and favorable nonlinear property, is a promising candidate system for tailoring important optical properties through modification of glass composition. In this context, a systematic study on ternary As–S–Se glass, chalcogen-rich versus well-studied stochiometric compositions, has been carried out using three different techniques: Raman spectroscopy, x-ray photoelectron spectroscopy, and extended x-ray absorption fine structure spectroscopy. These complementary techniques lead to a consistent understanding of the role of S/Se ratio in chalcogen-rich As–S–Se glasses, as compared to stochiometric composition, and to provide insight into the structural units (such as the mixed pyramidal units) and evidence for the existence of homopolar bonds (such as Se–Se, S–S, and Se–S), which are the possible structural origin of the high nonlinearity in these glasses. [ABSTRACT FROM AUTHOR]

Examines the effects of positive nitrogen implantation in amorphous silicon carbide films deposited on silicon substrates by relative frequency sputtering. Use of x-ray photoelectron spectroscopy and Auger electron spectroscopy; Correlation between the formation of silicon carbonitrides and the dynamical behavior of the carbon in the implanted layer; Details of the ion-induced modifications of the films.

Presents information on a study that examined electron spectroscopy for chemical analysis (ESCA) measurement results on thin SiO[sub2]/Si samples. Summary of conventional ESCA measurements; Problems associated with ESCA measurements; Conclusions.

Presents a surface analysis of bismuth-based cuprates superconductors through secondary ion mass spectrometry and X-ray photoelectron spectroscopy. Properties of cuprates superconductors; Discussion on kinetic energy distributions for secondary negative ions; Explanation for the emission of small clusters in bismuth-based cuprates.