Epitaxial ferroelectric thin films of lead zirconium-titanium oxide, Pb(Zr0.53Ti0.47)O3 (PZT), were successfully grown on SrTiO3, LaAlO3, and Sr(Nb)TiO3 single crystal substrates by a modified RF sputtering technique at high oxygen pressures. The structural properties of the films were evaluated by θ/2θ, ω and ø scans. From these data the crystalline orientation relationships may be extracted. For films grown on SrTiO3 and Sr(Nb)TiO3 substrates, the following orientation relationships were determined: PZT [001] parallel to [001] of the substrate, and PZT [100] parallel to [100] of the substrate. Films grown on LaAlO3 substrates showed a bi-domain crystalline structure with orientation relationships as follows: PZT [100] parallel to [001] of the substrate and PZT [001] parallel to [001] of the substrate. This work was focused to the determination the strain and grain size coefficients, and the analysis of their contribution on the peak broadening in the XRD patterns, and in considering their effects over the ferroelectric behavior. From Williamson-Hall plots, it was possible to conclude that the enhancement of the crystalline film properties (epitaxy and single crystalline domains) reduce the short range strains contribution to peak broadening. On other hand, the grain size contribution to peak broadening was increased with the enhancement of the film cristallinity.

Novel metal/dielectric material combinations are becoming increasingly important for reducing the resistance-capacitance (RC) interconnection delay within integrated circuits (ICs) as the device dimensions shrink to the sub-micron scale. Copper (Cu) is the material of choice for metal interconnects and SiO2 (with a dielectric constant k = ∼ 3.9) has been used as an interlevel dielectric material in the industry. To meet the demands of the international road map for semiconductors, materials with a significantly lower dielectric constant are needed. In this study, the effects of porosity and layer thicknesses on the mechanical properties of a multilayer thin film (Cu, Ta and SiO2)-substrate (Si) system are examined using nanoindentation and finite element (FE) simulations. A micromechanics model is first developed to predict the stress-strain relation of the porous silica based on the homogenization method for composite materials. An FE model is then generated and validated to perform a parametric study on nanoindentation of the Cu/Ta/SiO2/Si system aiming to predict the mechanical properties of the multilayer film stack.

The elastic behavior of gold thin films deposited onto Kapton substrate has been studied using in-situ tensile tester in a four-circle goniometer at a synchrotron beam line (LURE facility, France). Knowing the stress tensor in the film, the strong {111} fibre texture was taken into account using the Crystallite Group Method (CGM). CGM strain analysis allows predicting a non linear relationship between strain and sin2 Ψ obtained for the thin films due to the strong anisotropy of gold. In contrast, the average of strains in longitudinal and transversal directions varies linearly with sin2 Ψ. The evolution of the slope of these curves as a function of the applied stresses in the film allowed determining the single-crystal elastic constant s44 of thin gold films.

The height difference Δhb between the ideally sharp Berkovich indenter tip and a Δhb rounded tip was measured by direct observation using atomic force microscopy (AFM). The accuracy of the indirect area function method for measuring h was confirmed. The Δhb indentation size effects (ISE) in (100) single crystal copper, (100) single crystal tungsten, and fused quartz were characterized by applying the ISE model considering the rounded tip effect. The model fits the data these materials well, even though fused quartz does not deform by dislocations. However, a very small value of the ISE characteristic length h' was obtained for fused quartz. The present h' value for (100) copper is 32% larger than a previously-measured value for polycrystalline copper. This may indicate that grain boundaries suppress the dislocation activity envisioned in the ISE model.

Strained-silicon (ε -Si) is essential for future nanoscale MOSFET devices. In this paper we report on the dynamics of strain relaxation in Si/SiGe heterostructures, investigated by transient nonlinear finite element analysis. The contribution to total misfit strain is found largely plastic in the graded SiGe layer and the top of the Si substrate, while it is mainly elastic in the strained Si layer and part of the SiGe constant layer. The calculated lattice parameter for the strained Si layer is about 5.47Å for Si0.8Ge0.2 and 5.52 Å for Si0.6Ge0.4. Calculated threading dislocation density was about 5.6x105 cm-2 for x=0.20 and 2.17x106cm-2 for x=0.40. A plastic strain rate of 8.4x10-3s-1 for Si0.8Ge0.2 and 4.1x10-2 s-1 for Si0.6Ge0.4 leading to a density of moving dislocations of ~2.2x109 cm-2 and ~ 1010cm-2, respectively, have been obtained. The elastic strain in the strained-Si layer appeared to increase with increasing the cooling rate, while plastic work was found to be independent of cooling rates.

Bi2(Zn1/3Ta2/3)2O7 (BZT) thin films were grown on the (111) oriented Pt/TiOx/SiO2/Si substrates using a pulsed laser deposition (PLD) technique. BZT thin films deposited at an oxygen partial pressure of 400 mTorr have the non-stoichiometric anomalous cubic phase despite the BZT target was the monoclinic phase. Compositions, the lattice mismatch, the interfacial layer and the residual stress in the film were investigated as the factors which may affect the formation of the anomalous cubic phase. Among them, the coherent interfacial layer which formed at high oxygen pressures resulted in the formation of the cubic phase by reducing the internal stress.

NiCr films were thermally evaporated on the Mn-Ni-Co-O thick-film substrates. The NiCr/Mn-Ni-Co-O bi-layer systems were tested in a thermal shock chamber with three temperature differences of 150, 175 and 200°C. The systems were considered to have failed when the sheet resistance of NiCr films changed by 30% relative to an initial value. As the cyclic repetition of thermal shock increased, the sheet resistance of NiCr coatings increased. The Coffin-Manson equation was applied to the failure mechanism of cracking of NiCr coatings and the SEM observation of cracks and delamination in NiCr coatings due to thermal cycling agreed well with the failure mechanism.

Laser Induced Delamination is a novel technique aimed at measuring the practical work of adhesion of thin polymer coatings on metal substrates. In this technique a laser pulse is used to create initial blisters which initiate further delamination of the film under the blister pressure. A simple elastic model is developed to describe the formation of the blisters. The model predicts the values for the blister height and pressure, which are in fair agreement with the experimental results. In order to account for possible plastic deformations, simulations using a finite element model with a mixed mode cohesive zone were carried out. The calculated stress fields are in agreement with those predicted by the elastic model suggesting that the contribution of plastic deformation to the measured work of fracture is rather limited.

Measurements are carried out on a number of samples, presenting ECCS steel substrate covered with 35 μm thick polyethylene terephthalate (PET) film. The tensile stresses created in the film at the interface required for delamination are estimated at 7-8 MPa, which corresponds to the practical work of adhesion G = (0.6± 0.1) J/m2.

Microactuators fabricated with NiTi thin films take advantage of the shape memory effect's large energy density (∼5-10 joules/cm3) and high strain recovery (∼8%). Microelectromechanical Systems (MEMS) designed with these actuators can serve as biosensors, micro-fluidic pumps or optical switches. However, the fundamental mechanical properties of these shape memory NiTi films have not been fully characterized with micro-scale test structures. Equiatomic NiTi thin films were deposited by co-sputtering NiTi and Ti targets with the intension of fabricating such test structures. Dual cathodes allowed direct control of the film composition by adjusting the Ti cathode power. Energy Dispersive Spectroscopy (EDS) quantified the film composition relative to pure standards. A thin (∼50 nm) chromium film on a pure silicon substrate created excellent film adhesion. Oxidized Si wafers did not bond with the Cr and NiTi films. This deposition method enabled control of film composition and the necessary adhesion.

Anatase-TiO2 films (thickness 100-1000 nm) were grown on glass, sapphire, and Si(100) substrates using pulsed dc-magnetron reactive sputtering. By measuring the curvature of substrates before and after the thin film deposition, the residual stresses were determined. These results clearly show that the bi-axial stresses are compressive type and decreases with the increasing film thickness. The Raman spectra of these films were measured with two different excitation wavelengths (514 and 785 nm) and the thickness dependent shifts of Eg phonon mode were studied. The dominant 144 cm-1 Eg mode in TiO2 anatase clearly shifts to a higher value by 0.45 to 17.4 cm-1 depending on the type of substrate and the thickness of the film. Maximum shift was seen for the films on glass substrate indicating a higher bi-axial compressive stress in agreement with the curvature measurements. The excitation wavelength dependent shift of Eg mode clearly shows that the bi-axial stress increases along the film depth, being larger at the film/substrate interface.

Rapid lateral solidification via excimer laser melt processing is demonstrated in 200 nm thick pure Cu and Au films, encapsulated above and below by amorphous SiO2. Mask projection irradiation is used to selectively melt lines 3 to 30 m wide in the metal films, with lateral solidification proceeding transversely from the edge to the middle of the line. Encapsulation with the SiO2 overlayer and control of the fluence are found to be crucial parameters necessary to prevent dewetting while the films are molten. Transmission electron microscopy reveals large columnar grains with twin structures and other defects typical of rapid solidification.

SrRuO3 (SRO) thin films were grown on SrTiO3 (100) substrates using the pulsed laser deposition method. The films' growth properties widely changed in response to different working oxygen partial pressures. An island growth mode was dominant for low pressures up to 10 mTorr followed by a step flow growth mode at 60 mTorr and step flow plus 2 D growth at 200 mTorr then reverting back to island growth at 300 mTorr. Significant out-of-plane strains of SRO films were observed for low growth pressures (up to 10 mTorr) but became notably reduced at 60 mTorr and continued to decrease gradually with further pressure increases. Formation of Ru vacancies occurs regardless of the working pressure values and appears to be minimized at 60 mTorr. Highest TC's were obtained in films exhibiting the step flow growth mode. The role of Ru deficiencies in relation to strain, growth mode, and magnetic properties is discussed.