Reliable Switching Operation Research Articles

Improved reset breakdown strength in a HfOx-based resistive memory by introducing RuOx oxygen diffusion barrier

We investigated the reset breakdown phenomenon of HfOx-based resistive memory for reliable switching operation in a fully CMOS compatible stack. Through the understanding on the effect of electrode materials and device area, our findings show that observed failure is attributed to additional oxygen vacancies close to the electrode interface, where switching is occurred. Therefore, RuOx serving as an oxygen diffusion barrier was introduced to suppress the generation of unwanted oxygen vacancies by preventing out-diffusion of oxygen through the electrode. As a result, significantly enhanced breakdown strength in HfOx/RuOx stack is achieved and resulting in improved cycle endurance with larger on/off ratio.

Circuit Modelling and Eigenfrequency Analysis of a Poly-Si Based RF MEMS Switch Designed and Modelled for IEEE 802.11ad Protocol

This paper presents the equivalent circuit modelling and eigenfrequency analysis of a wideband robust capacitive radio frequency (RF) microelectromechanical system (MEMS) switch that was designed using Poly-Si and Au layer membrane for highly reliable switching operation. The circuit characterization includes the extraction of resistance, inductance, on and off state capacitance, and Q-factor. The first six eigenfrequencies are analyzed using a finite element modeler, and the equivalent modes are demonstrated. The switch is optimized for millimeter wave frequencies, which indicate excellent RF performance with isolation of more than 55 dB and a low insertion loss of 0.1 dB in the V-band. The designed switch actuates at 13.2 V. The R, L, C and Q-factor are simulated using Y-matrix data over a frequency sweep of 20-100 GHz. The proposed switch has various applications in satellite communication networks and can also be used for devices that will incorporate the upcoming IEEE Wi-Fi 802.11ad protocol.

If It Ain't Broke...

As requirements for service reliability have increased, many utility asset managers are also facing pressures to reduce maintenance costs while squeezing more performance from existing-and often aging-equipment. High-voltage circuit breakers provide a case in point. Not only are high-voltage breakers essential to the protection of other system components under fault conditions, their reliable switching operation is necessary for maintaining optimal system conditions. A breaker's failure to operate as required can result in equipment damage, increased system disturbance, and loss of load. With many years of experience, utilities have established programs for maintaining circuit breakers in good operating order. Because of their sheer numbers, however, breakers represent a significant portion of a utility's power delivery maintenance budget. The maintenance challenge is made more complicated by the fact that many breakers, including breakers that have been in service for decades, remain idle for extended periods during normal system conditions. In response to pressures to reduce maintenance expenses, many utilities have moved away from the original manufacturer's maintenance recommendaticondition-based approachesons, which were principally based on time in operation and number of operations, and toward reliability-centered maintenance (RCM) and condition-based approaches.

Bistability and Switching Properties of Semiconductor Ring Lasers With External Optical Injection

We investigate both analytically and numerically the switching, locking and stability properties of a bistable semiconductor ring laser subject to an external optical injection. Minimum optical power required for the injected signal at certain frequency to switch the lasing direction of a bistable semiconductor ring laser from its initially lasing direction to initially nonlasing direction is determined. Locking to the injected signal and stability of the switched laser are investigated to give an area of reliable switching operation. Correspondingly, numerical simulation has been carried out to find successful switching and stable locking region with variable injection power and frequency, and is compared with the analytical results. The region obtained from simulation coincides well with the intersection of switching, locking and stable locking regions. The relation between switching speed and parameters of injected source is also studied numerically.

Free-Space Optical Switch Modules Using Risley Optical Beam Deflectors

This paper describes new optical switch modules based on Risley optical beam deflectors. The Risley deflector consists of two wedge-shaped prisms and precisely controllable rotation mechanisms. An optical beam can be deflected to the direction of two axes by rotating each prism independently. The deflectors potentially have a self-latching function, which provides a reliable switching operation, and a large-deflection angle of 19.2°, which makes the switch compact. We experimentally confirmed that prototype switch modules, hardware volume: 15×15×31 mm3, deflection angle: <19.2°, have a scalability of the switch up to 256 ports, low-loss characteristics of 1.0–1.5 dB, and switching time of within 6 s.

A three-dimensional MEMS optical switching module having 100 input and 100 output ports

This paper describes an optical switching module based on microelectromechanical systems (MEMS) two-axis tilt mirror arrays and low-cost highly accurate free-space optics. The MEMS mirror arrays are integrated on single-crystal silicon wafers and provide reliable switching operation at a low driving voltage. The free-space optics consists of two-dimensional optical fiber and microlens arrays based on low-cost and highly accurate polymer-based components. They provide a compact switching module (approximately 80/spl times/60/spl times/35 mm [170 cc]) and are assembled passively by using dowel pins. A prototype switch module with 100-ch optical fiber I/O has a low coupling loss of 4.0 dB, a low crosstalk within -60 dB, and switching time of 3 ms.