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The formation of conductive percolation path in high-κ (HK)/interfacial layer (IL) dielectric stack is accompanied by dynamic changes in the electrical and chemical properties at the nanometer length scale. It is therefore essential to study these breakdown (BD) events using high-precision nanoscale characterization tools to investigate the physical mechanisms of failure for advanced HK dielectric based devices. In this work, we carry out a new method for electrical nanoprobing of HfO2/SiOx (x

Control of photonic crystal resonances in conjunction with large spectral shifting is critical in achieving reconfigurable photonic crystal devices. We propose a simple approach to achieve nano-mechanical control of photonic crystal resonances within a compact integrated on-chip approach. Three different tip designs utilizing an in-plane nano-mechanical tuning approach are shown to achieve reversible and low-loss resonance control on a one-dimensional photonic crystal nanocavity. The proposed nano-mechanical approach driven by a sub-micron micro-electromechanical system integrated on low loss suspended feeding nanowire waveguide, achieved relatively large resonance spectral shifts of up to 18 nm at a driving voltage of 25 V. Such designs may potentially be used as tunable optical filters or switches.

We present dynamic tuning of optical resonance using microelectromechanical systems (MEMS)-driven coupled photonic crystal (PhC) nanocavities. The device consists of an air-suspended one-dimensional PhC nanocavity coupled to input and output waveguides and a perturbing nanocavity attached to a submicrometer MEMS comb drive. Resonance tuning is achieved through varying the gap between the two coupled cavities. We demonstrate experimentally that resonance can be tuned up to 8nm with no significant deterioration in the Q factor. The proposed mechanism potentially enables a new platform of on-chip photonic devices that can achieve a large tuning range with low power and small footprint and may find useful applications in tunable optical/photonic devices.

A wide-range split-ladder photonic crystal cavity which is tuned by changing its intrinsic gap width is designed and experimentally verified. Different from the coupled cavities that feature resonance splitting into symmetric and anti-symmetric modes, the single split-ladder cavity has only the symmetric modes of fundamental resonance and second-order resonance in its band gap. Finite-difference time-domain simulations demonstrate that bipolar resonance tuning (red shift and blue shift respectively) can be achieved by shrinking and expanding the cavity's gap, and that there is a linear relationship between the resonance shifts and changes in gap width. Simulations also show that the split-ladder cavity can possess a high Q-factor when the total number of air holes in the cavity is increased. Experimentally, comb drive actuator is used to control the extent of the cavity's gap and the variation of its displacements with applied voltage is calibrated with a scanning electron microscope. The measured wavelength of the second-order resonance shifts linearly towards blue with increase in gap width. The maximum blue shift is 17 nm, corresponding to a cavity gap increase of 26 nm with no obvious degradation of Q-factor.