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Cross sectional nanoindentation (CSN) is a technique recently developed to study thin film interface decohesion in a microscopic scale. Controlled interfacial microcracks are induced at the interfaces of interest by indenting in a cross section of a multilayer thin film structure. The correlation between the observed cracking phenomena and the corresponding load vs. indenter tip displacement curves is discussed. An additional benefit of the CSN technique is the low scatter of results obtained for the mean interfacial crack lengths produced by identical tests. The observation of the interfacial crack front by scanning electron microscopy shows clear differences between the interfacial fracture micro-mechanisms present in samples with good and bad adhesion behaviour.Este trabajo presenta una nueva técnica de nanoindentación en sección transversal desarrollada para el estudio a escala microscópica de los fenómenos de descohesión en intercaras de películas delgadas. El ensayo consiste en generar grietas en las intercaras de interés a partir de una indentación realizada sobre la sección transversal de una estructura multicapa de películas delgadas. La técnica se aplicó a dos muestras con tres películas delgadas (SiO2/Al-Cu/SiO2) depositadas sobre una oblea de silicio monocristalino que presentaban buena y mala adhesión. Se discute la correlación entre el agrietamiento observado y las correspondientes curvas carga aplicada frente a desplazamiento de la punta del indentador registradas durante el ensayo. Una ventaja de esta técnica es la baja dispersión de la longitud de las grietas obtenida en ensayos realizados en idénticas condiciones. Finalmente, la observación mediante MEB del frente de la grieta interfacial muestra claras diferencias en los micromecanismos de fractura presentes entre las muestras con mala y buena adhesión.

An unexpected mode of plastic deformation was observed in damascene Cu interconnect test structure during an in-situ electromigration experiment and before the onset of visible microstructural damages (void, hillock formation). We show here, using a synchrotron technique of white beam X-ray microdiffraction, that the extent of this electromigration-induced plasticityis dependent on the line width. The grain texture of the line might also play an important role. In wide lines, plastic deformation manifests itself as grain bending and the formation of subgrain structures, while only grain rotation is observed in the narrower lines. This early stage behavior can have a direct bearing on the final failure stage of electromigration.

We investigated the effect of intermediate cylindrical confinement with locally repulsive walls on the segmental and entanglement dynamics of a polymer melt by quasielastic neutron scattering. As a reference, the corresponding polymer melt was measured under identical conditions. The locally repulsive confinement was realized by hydrophilic anodic alumina nanopores with a diameter of 20 nm. The end-to-end distance of the hydrophobic infiltrated polyethylene-alt-propylene was close to this diameter. In the case of hard wall repulsion with negligible local attraction, several simulations predicted an acceleration of segmental dynamics close to the wall. Other than in attractive or neutral systems, where the segmental dynamics is slowed down, we found that the segmental dynamics in the nanopores is identical to the local mobility in the bulk. Even under very careful scrutiny, we could not find any acceleration of the surface-near segmental motion. On the larger time scale, the neutron spin-echo experiment showed that the Rouse relaxation was not altered by confinement effects. Also the entanglement dynamics was not affected. Thus at moderate confinement conditions, facilitated by locally repulsive walls, the dynamics remains as in the bulk melt, a result that is not so clear from simulations. [ABSTRACT FROM AUTHOR]

Nanopillars, nanotubes and nanofibers of transparent polymethyl methacrylate (PMMA) polymer with Yb:Ln:Lu2O3 (Ln�=�Er or Tm) nanoparticles (NPs) (≈30–35 nm average size) have been prepared by infiltration of anodized aluminum oxide hexagonally nanopatterned templates. The outer diameter of these nanostructures is in the 330–400 nm range, with lengths up to 50 μm and a period distance of 430 nm. These nanostructures show visible upconversion (UC) emissions under excitation with 978 nm light. The steady state temperature of the polymer nanostructures is optically evidenced by the Er3+ UC emission and optically controlled around the PMMA glass transition temperature by the excitation light, introducing a new method for NP storage in a solid and potential optically induced particle release. Full color emission is shown in tridoped (Yb:Er:Tm) samples. [ABSTRACT FROM AUTHOR]

The effect of PMOS transistor negative bias temperature instability (NBTI) on product performance is a key reliability concern. As technology scales and device dimensions shrink, the trend in the V T variability at both time zero and after NBTI aging increases. The time0 V T variability can be explained by the random nature of dopants, whereas the randomly generated defects in the gate oxide can account for the aging-induced device DeltaV T variability. This paper focuses on the bias temperature instability stress-induced device DeltaV T variability and the trend across several technology generations. The remarkable correlation of aging-induced DeltaV T variability to the gate oxide area suggests that the continued device geometry scaling will increase the aging-induced variability. For the first time, aging-induced DeltaV T variability was characterized on transistors fabricated with high-kappa gate dielectric that also showed similar dependence to the gate oxide area. [ABSTRACT FROM PUBLISHER]

Analyzes the electromigration voids in passivated aluminum lines through field emission scanning electron microscope. Relation of electromigration voids to electron wind at high spatial resolution; Determination of surface migration activation energy; Disappearance of stationary voids in the presence of electrical stress.