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In this study, we fabricate an electrode structure, in which a carbon nanotube (CNT) film is coated on the composite of carbon nanotubes (CNTs) and polydimethylsiloxane (PDMS). Electromechanical tests disclose that incorporation of a high density of well-dispersed CNTs (with the aid of UV/O3 treatment) in the PDMS substrate offers an alternative current path when the CNT film cracked, helping demonstrate much improved electromechanical characteristics. Further analysis using scanning electron microscopy (SEM) combined with the data from the electromechanical tests illuminates some interesting electromechanical features and the failure mechanism of the material.

We have found that stress relaxation of nanoscale Al thin films is strongly dependent on both film thickness and temperature. Films 33, 107, and 205 nm thick prepared by evaporation onto a silicon nitride membrane substrate were studied using membrane resonance. A single thermal cycle to 300 °C was used to establish a stress, after which the time dependence of the stress was measured for the three film thicknesses at 50, 75, and 100 °C. The relaxation rate is highest for the highest temperature and the thinnest film. A dislocation locking mechanism is suggested as a possible explanation for the observed thickness dependence.

Two kinds of epitaxial Sr–Bi–Ta oxides were grown on La0.5Sr0.5CoO3(001)/LaAlO3(001) substrates by pulsed laser deposition. At a temperature higher than 650 °C, c-axis oriented SrBi2Ta2O9 films could be deposited epitaxially. At 550 °C, an epitaxial film with a cubic fluorite-like phase could be grown. Although the film with the cubic phase does not show ferroelectric properties, it has good electrical properties which are suitable for high capacitance applications.

We have found that thin aluminum films at room temperature exhibit changes in elastic modulus of 25% or more over periods of an hour under stress by using a novel capacitance bulge system. Furthermore, we have strong evidence that this change is due to linear viscoelasticity. Such large changes in modulus can affect the stability and performance of microelectromechanical systems structures and need to be understood and controlled. These results are also proof that linear viscoelastic analysis is as appropriate for thin metal films as it is for many polymer systems.