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The crosstalk effects in single- and double-walled carbon-nanotube (SWCNT and DWCNT) bundle-interconnect architectures are examined. The studies have shown that, compared with the SWCNT bundle, the DWCNT bundle interconnect has led to a reduction of crosstalk-induced time delay, while the peak voltage of the crosstalk-induced glitch in SWCNT and DWCNT bundle interconnects is in the same order as that of Cu wires.

Various test patterns are used to analyze the stress migration (SM) behavior in narrow copper (Cu) damascene interconnects, connecting in narrow or wide lines. The results of the analysis shows that the SM phenomenon in such lines is highly affected by the placing of the vias at the edge of the M1 line, which is then used to explain the effect of the via arrangement close to the edge of the lower lines on the SM failure in the interconnects.

A high-speed tensile facility (HSTF) is applied to interrupting the tests for pure copper specimen bars controlled locally at different levels of elongation. The results of scanning electron microscopical (SEM) investigation of the recovered pure copper specimens have shown that the void evolution near the surface of the minimum cross-section of the necking area is more severe than that at the middle of the necking area.

Molecular dynamics simulations are used for examining the mechanical deformation of bicrystalline metallic nanowires with different interfaces. The impact of interfacial microstructure on the mechanical behavior is elucidated by exploring the stress-strain property and the stress concentration along the tensile direction.

Several experimental studies are conducted to determine the resistivities and microstructures exhibited by the 50 nm wide Cu wire that is prepared by the high heating rate. The resistivity of the wires is shown to highly decrease with an increase in the annealing temperature.

Molecular dynamics simulations are used for examining the shock response of idealized hexagonal columnar nanocrystalline Cu, including plasticity, local shear, and spall damage during dynamic compression, release and tension. Shock loading is applied along three principal directions of the columnar Cu sample, which has displayed a strong anisotropy in the response to shock loading and release.

The stress evolution model (SEM) is used for calculating the void nucleation time in a large number of short interconnects. The assumption of a lognormal grain size distribution and a normal distribution of diffusion activation energies have shown the nucleation time distribution to be close to lognormal.

Electromigration results are described for a ducal damascene structure with copper metallization and a low-k dielectric material and it is shown that the threshold failure time has scaled differently with current density from the median time to failure. The observed current density dependency, along with scanning electron microscopy cross sections of stressed samples and Monte Carlo simulations of failure distributions, has shown that both void nucleation and void growth is considered for accurate modeling of the electromigration lifetime.

The resonant-ultrasound spectroscopy is used for observing very large and rapid evolution of elastic constants in deposited copper and silver films. Diffusion of atoms along the grain boundary region is one of the reasons for the evolution and it is shown that the activation energy is much smaller than that for grain-boundary diffusion in bulk materials.

First-principles study is used for analyzing the copper adhesion on Ta(110) and Ru(0001) surface with the density functional theory. The results have shown that Cu adsorbed on Ta(110) surface is desorbed and agglomerated on the top of the second Cu atom layer.

The shock Hugoniot of single copper is described for stresses below 66 GPa and symmetric impact experiments are used for measuring the Hugoniots of three different crystal orientations. The studies have shown that at the lowest stresses, the sound speed in Cu is extracted from the photonic doppler velocimetry (PDV) data.

The spall damage of single crystal Cu under supported and decaying shock wave loading is examined by using molecular dynamics simulations. Multiple spall events are shown to be independent of each other at the early stage of spallation and the method has worked better for large target-to-flyer plate thickness ratio R (Taylor waves) than for small R (square waves).

The first dynamic study of damage mechanisms in nanosized on-chip Cu interconnects caused by stress-induced voiding in advanced integrated circuits is described. The void growth rate has depended on the Cu thin film material and its microstructure and the Cu microstructure in the surroundings of the formed void has showed that Cu grains are (111) oriented to the wafer surface.

Creep tests are conducted on a nanocrystalline Cu at room temperature and the results at very low strain rates are consistent with Coble creep. The stress-strain rate behavior of the nanocrystalline Cu has shown that as the strain rate decreases, the deformation mechanism has changed from predominantly dislocation activity to diffusion Coble creep, as observed by the strain rate sensitivity on stress and activation volume.

The drift/diffusion model describing the effect of the transport and accumulation of copper ions on the time of failure of dielectrics is used for including metallic barriers and the effect of an elastic drift term. The change in the value of the field acceleration parameter is linked to many factors including the transport of oxidizing species through the barrier responsible for copper ion formation and the injection and motion of electrons and holes, which are changed in the presence of a barrier between the metal and dielectric.

Submicrosecond time scale underwater electrical explosions of planar Cu and Al wire arrays are studied by using hydrodynamic simulations. The studies have shown that electrical explosion of the Al wire array has allowed almost double the energy to be transferred to the water flow due to efficient combustion of the Al wires.

Silylated mesoporous silica (MPS) films capped with a Cu overlayer fracture near the Cu/MPS interface at a distance has correlated with the Cu penetration depth into MPS. Silylation has lowered the tensile stress and the fracture toughness of MPS films, but the extent of decreases in these properties has decreased the overall driving force for cracking.

Epitaxial nanotwinned Cu films with an average two spacing have displayed a high rate of strength-to-electrical resistivity. The studies have shown that in twinned Cu, the ratio has increased continuously with decreasing twin spacing down to a few nanometers and hence nanoscale growth twins can be used for achieving a higher strength-to-resistivity ratio than higher-angle grain boundaries.

The three-dimensional classical molecular dynamics simulation was used to examine the deposition and annealing behaviors of Al atoms on rough Cu (111) surface on the atomic scale. The significant intermixing between Al and Cu which rapidly occurs due to annealing at 700 K with decrease in the surface roughness provide insight into the exchange process of Al with substrate Cu during the initial stage of high temperature annealing.

Thermomigration (TM) in Sn58Bi solder is detected in Cu/Sn58Bi/Ni solder joints supplied with direct current and it has assisted or counteracted electromigration (EM) on the diffusion of Bi atoms. EM-enhanced cross interaction between Cu and Ni across the solder joint is detected, which has led to the intermetallic compound (IMC) at Ni side or the Cu side of the joint that electron flow is from the Cu side to the Ni side is thinner than that of corresponding IMC in the joint stressed with current in opposite direction.

The semiconductor theories and methods were used to examine the underlying physical mechanism of the so-called colossal dielectric constant phenomenon in Ca[Cu.sub.3][Ti.sub.4][O.sub.12] (CCTO) thin films. The similar defect concentrations observed for two contact types, namely, metal-semiconductor and metal-insulator-semiconductor junctions, indicated an inherent feature of high defect concentration in thin films.

Ultrahigh pressure and strain-rate reverberation experiments are performed in tantalum, aluminum, and copper to assess the yield strength behavior in this extreme regime. The experimental results revealed that the measurement sensitivity to yield strength is dominated by the lateral wave effects or impeded by the occurrence of spall.

Nanoindentation creep tests are performed in the depth range from about 28 to 190 nm on nanocrystalline (NC) and ultrafine grain (UFG) Cu films to observe pronounced indentation size effects on hardness, creep strain rate ([epsi]), and strain rate sensitivity ([m.sub.c]). The creep deformation of NC and UFG Cu are found to be dominated by grain-boundary-mediated process and diffusion along the interface of tip sample, respectively, under a critical [h.sub.c].

Experiments are carried out on stress-induced void formation in ultrathin Cu wires while varying heat-treatment temperature, wire dimensions and overlayer thickness. A void formation model is constructed that has described how local strain at four trench corners is relaxed in the buried wire in the annealing process.

The melting of shock-loaded single crystal Cu during release from solid shock states is examined by using molecular dynamics simulations. The shocked crystal has undergone superheating before release melting and the release path is regarded as an isentrope regardless of release melting.

The effects of the surface roughness and applied loads on the electrical contact resistance of three-dimensional Cu-Cu bonded interconnects are examined. The results have shown that as the surface roughness of the Cu bonding layer has increased or as the bonding load has decreased, the specific contact resistance of the bonded interconnects has increased.

An edge displacement method is employed to examine the Electromigration in Sn-Cu intermetallic compounds. The [Cu.sub.6][Sn.sub.5] compounds are found to be more susceptible to electromigration compared to [Cu.sub.3]Sn compounds and also the Sn-Cu compounds have better electromigration resistance than eutectic SnAgCu solder.

In situ stress measurements were performed during high frequency pulse electrodeposition of nanotwinned Cu thin films to understand the periodic stress changes during pulse-on and pulse-off periods. The stress profile showed an abrupt increase in tensile stress to about 400 MPa during the pulse-on period and a stress relaxation during the pulse-off period.

Different dislocation processes observed for copper and iron operative under high rate loading by impact-induced shock tests as compared with shockless isentropic compression experiments (ICEs) are described. The extensive shock measurements observed for plate impact tests in iron are also explained in terms of plasticity-control via the nucleation of deformation twins at the propagating shock front.

An extensive analysis of resistance evolution during package electromigration (EM) tests is described. The observed increase in time of failure (TTF) standard deviation at low linear function (jL) is explained by the spread of critical void shapes.

The full Penn algorithm (FPA) is adopted to derive the energy loss function for the calculation of differential inelastic mean free paths (IMFPs). The results of the energy distributions and the secondary electron emission yields for Al and Cu have agreed well with the experimental results.

Cu contamination of a 'model' grain boundary (GB) created by direct silicon bonding of (110)/(100) wafers is examined by monitoring the hole emission from GB states. The electrically active Cu-related states present at the GB are generated from the surfaces of localized Cu precipitates, whereas quench cooling from a higher contamination temperature has produced a lower density of large precipitates which has resulted in a reduced chemistry of Cu-related GB states.

The interconnect microstructures combined with the one-dimensional stress evolution equation of Korhonen is employed to model the electromigration (EM) lifetime in short copper interconnects. The results have shown the lognormal distribution of EM failure times and the normal distribution of activation energies together with the permanence property of the lognormal distribution.

A pulse electric brush-plating technique is used for synthesizing bulk nanocrystalline-Cu (nc-Cu) and the effect of strain rate on the plastic deformation behavior of this nc-Cu is examined. The results have provided insight into the transition and unusual compressive behavior of nc-Cu due to its fine and uniform grain structure and predominant high-angle grain boundaries (GBs).

The inner-sphere electron transfer mechanism during the catalytic reduction of molecular oxygen by copper amine oxidases is analyzed. The electron transfer from the topaquinone (TPQ) semiquinone has followed in the first irreversible step to form a peroxide intermediate driving the reduction of [O.sub.2].