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The structural flexibility of low dimensional nanomaterials offers unique opportunities for studying the impact of strain on their physical properties and for developing innovative devices utilizing strain engineering. A key towards such goals is a device platform which allows the independent tuning and reliable calibration of the strain. Here, we report the fabrication and characterization of graphene nanoelectromechanical resonators (GNEMRs) on flexible substrates. Combining substrate bending and electrostatic gating, we achieve the independent tuning of the strain and sagging in graphene and explore the nonlinear dynamics over a wide parameter space. Analytical and numerical studies of a continuum mechanics model, including the competing higher order nonlinear terms, reveal a comprehensive nonlinear dynamics phase diagram, which quantitatively explains the complex behaviors of GNEMRs. [ABSTRACT FROM AUTHOR]

We present a systematic study of the dependence of breakdown voltages on oxide thickness d in Al–AlO[sub x]–Al thin-film capacitor structures. For sufficiently thin dielectrics, we find that a significant portion of the measured breakdown potential V[sub b] occurs across the electrode interfaces, thereby leading to an overestimate (V[sub b]/d) of the true breakdown electric field E[sub b] across the dielectric. By modeling this interface contribution as an “interface” capacitance in series with the geometric “bulk” capacitance, we find for high-quality rf magnetron-sputtered AlO[sub x] dielectrics that E[sub b] is independent of d over the range 30–300 Å. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]