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Abstract-Electrostatically driven MEMS devices commonly operate with electric fields as high at 10 8 V/m applied across the dielectric between electrodes. Even with the best mechanical design, the electrical design of these devices has a large impact both on performance (e.g., speed and stability) and on reliability (e.g., corrosion and dielectric or gas breakdown). In this paper, we discuss the reliability and performance implications of leakage currents in the bulk and on the surface of the dielectric insulating the drive (or sense) electrodes from one another. Anodic oxidation of poly-silicon electrodes can occur very rapidly in samples that are not hermetically packaged. The accelerating factors are presented along with an efficient early-warning scheme. The relationship between leakage currents and the accumulation of quasistatic charge in dielectrics are discussed, along with several techniques to mitigate charging and the associated drift in electrostatically actuated or sensed MEMS devices. Two key parameters are shown to be the electrode geometry and the conductivity of the dielectric. Electrical breakdown in submicron gaps is presented as a function of packaging gas and electrode spacing. We discuss the tradeoffs involved in choosing gap geometries and dielectric properties that balance performance and reliability.

A scalable, multiplexed ion trap for quantum information processing is fabricated and tested. The trap design and fabrication process are optimized for scalability to small trap size and large numbers of interconnected traps, and for integration of control electronics and optics. Multiple traps with similar designs are tested with $^{111}$Cd$^+$, $^{25}$Mg$^+$, and $^{88}$Sr$^{+}$ ions at room temperature and with $^{88}$Sr$^+$ at 6 K, with respective ion lifetimes of 90 s, 300 $\pm$ 30 s, 56 $\pm$ 6 s, and 4.5 $\pm$ 1.1 hours. The motional heating rate for $^{25}$Mg$^{+}$ at room temperature and a trap frequency of 1.6 MHz is measured to be 7 $\pm$ 3 quanta per millisecond. For $^{88}$Sr$^{+}$ at 6 K and 540 kHz the heating rate is measured to be 220 $\pm$ 30 quanta per second.

Electrically tunable membranes with controllable permeability have been experimentally demonstrated by combining nanostructured and microstructured superhydrophobic surfaces with the phenomenon of electrowetting. Electrowetting allows dynamical tuning of the contact angle that the liquid forms with the membrane nanofeatures and microfeatures, thus controlling the flow of the liquid through the membrane and, therefore, tuning the permeability of the entire structure. “Smart” electrochemical energy storage cells that can be activated on demand have been built by combining these membranes and microfabricated Zn∕MnO2 electrodes. A typical open-circuit voltage of 1.55V and capacity of 200μAh∕cm2 have been demonstrated.