Dielectric-breakdown-induced epitaxy: a universal breakdown defect in ultrathin gate dielectrics

The breakdown phenomena in SiO/sub x/N/sub y/ (EOT=20 /spl Aring/) gate dielectric under a two- stage constant voltage stress in inversion mode are physically analyzed with the aid of transmission electron microscopy. The results show that dielectric-breakdown-induced epitaxy (DBIE) remains as one of the major failure defects responsible for gate dielectric breakdown evolution even for a stress voltage as low as 2.5 V. Based on the results, the same failure mechanism i.e., presence of DBIE would be responsible for the degradation in ultrathin gate dielectrics for gate voltage below 2.5 V. It is believed that DBIE will be present in MOSFETs failed at nominal operating voltage.     

Advanced SPICE modeling of large power IGBT modules

An enhanced insulated gate bipolar transistor (IGBT) model based on the Kraus model with new derivations based on an extra parameter accounting for p-i-n injection was developed to allow simulation of both trench and DMOS IGBT structures. Temperature dependence was also implemented in the model. The model was validated against steady-state and transient measurements done on an 800-A 1.7-kV Dynex IGBT module at 25/spl deg/C and 125/spl deg/C. The Spice model has also shown excellent agreement with mixed mode MEDICI simulations. The Spice model also takes into account for the first time the parasitic thyristor effect allowing the dc and dynamic temperature-dependent latchup modeling of power modules as well as their temperature-dependent safe operating area.     

A novel energy‐retaining inverter for AC arc welding machines

A novel energy‐retaining power supply for AC arc welding machines is proposed in this paper. In this kind of power supply, current‐steering diodes connected across the output chokes keep the inductor current continuous and retain the energy during the commutation period, hence reducing the commutation time to ensure a better welding performance. In addition, the stored energy can be released in the next energy transfer cycle to raise the conversion efficiency. The circuit operations and design procedures are likewise examined thoroughly. Experimental results on a prototype inverter for driving a 100‐A AC arc welding machine are recorded to validate the effectiveness of the presented scheme. Copyright © 2010 John Wiley & Sons, Ltd.     

A simple control scheme for a single stage flyback LED driver

This study proposes a simple control scheme for using single‐stage flyback (SSF) converters in lighting source applications for LEDs. Among the advantages of the average current mode is an I/O current ripple that is only one‐half of the critical conduction mode (CRM). This condition helps extend the output capacitor lifetime while lowering the input EMI capacitance input EMI capacitance. The SSF converter proposed in this study operates in continuous conduction mode (CCM). In addition, two sample‐and‐hold (S/H) circuits are placed at the output voltage loop and feed‐forward path, respectively. Since these S/H circuits access the average output current and average feed‐forward voltage, the LED driver is unaffected by the 120‐Hz ripple noise, the total harmonic distortion (THD) is reduced, and the transient response of the output current is improved. Finally, the operation principles and design considerations of the studied LED driver are analyzed and discussed. A laboratory prototype is also designed and tested to verify the feasibility. Copyright © 2014 John Wiley & Sons, Ltd.     

面向微粒操纵的介电泳芯片系统研究

针对目前在纳米器件及传感器的制造中尚无对大量粒子进行有效操纵的方法,我们利用介电泳方法对大量微粒进行定位和传输操纵,介绍了利用MEMS工艺进行介电泳芯片加工的过程以及整个观测与实验系统的建立,通过有限元软件对传统介电泳和行波介电泳中电极阵列的电场分布进行求解,并在该实验系统下实现了对微通道中的悬浮高度和微粒的运动速度的测量.该实验系统的研究为液体环境下微纳颗粒的装配和分离提供了一条有效的技术路径.     

Sentences over Integral Domains and Their Computational Complexities

LetRbe a Hilbertian domain and letKbe its fraction field. Letψ(x₁, …, x_n, y) be a quantifier free arithmetical formula overR. We may also takeψ(x₁, …, x_n, y) to be an arithmetical formula overK[x₁, …, x_n] and write it asψ(y). In this paper we show that ifRhas enough non-units and x₁…x_n y ψ(x₁, …, x_n, y), called an ⁿ  sentence, is true inR, then y ψ(y) is true inK[x₁, …, x_n]. Also, ifR=K[T], whereKis an infinite integral domain andx₁…x_n y ψ(x₁, …, x_n, y)is true inR, then y ψ(y) is true inR[x₁, …, x_n]. These results are applied to find the upper and lower bounds of the time complexities of various decision problems on diophantine equations with parameters and arithmetical sentences. Some of the results are: 1. The decision problem of sentences and diophantine equations with parameters over the ring of integers of a global field are co-NP-complete. 2. The decision problem of sentences over the ring of integers of a global field is NP-complete. 3. LetKbe an infinite domain, the time complexities of the decision problems of equations with parameters and sentences over the polynomial ringK[t] are polynomial time reducible to factoring polynomials overK. 4. The decision problem of sentences over all algebraic integer rings is in P. 5. The decision problem of sentences over all integral domains with characteristic 0 is in P. 6. The time complexity of the decision problem of sentences over all integral domains is polynomial time reducible to factoring integers overZand factoring polynomials over finite fields.     

Phone‐Web: Accessing WWW using a telephone set

In order to provide a ubiquitous, comprehensive and versatile service on the WWW the development of a WWW telephone browsing system named Phone‐Web is proposed. This Phone‐Web browser system would act as an intermediary between the telephone user and Web sites, thereby facilitating access to the WWW from any phone. The Phone‐Web system would filter Web page information and then convert it into speech format. Users of the Phone‐Web system could retrieve and hear information stored on WWW servers by using telephone handsets. For this system to work it requires a new hypertext language “Hyper Phone Markup Language” (HPML) and a dedicated Phone‐Web browser. By using the proposed HPML language, Web page designers can easily specify service information in a set of HPML pages, which would be included in the site they are designing. The Phone‐Web browser would be capable of retrieving and then converting the HPML pages into speech patterns. By connecting to the Phone‐Web browser, telephone users can access any information on any site using the HPML language from any telephone anywhere in the world. However, HPML‐specified pages can also be accessed using existing browsers (e.g., Netscape Navigator, Microsoft Internet Explorer, etc.) This means that both telephone and computer users can now access the same set of Web pages to retrieve the same information. Therefore, instead of maintaining the existing two systems (access via the telephone or computer) service providers can now maintain one system, which would provide a versatile, and comprehensive service for users at all levels of Web‐literacy. This revised version was published online in August 2006 with corrections to the Cover Date.     

BiNem® manufacturing process for mass production

Abstract— As the need for high‐resolution ultra‐low‐power bistable displays grows, it is important to rapidly implement the mass‐production manufacturing of BiNem® LCDs. The cost‐effective approach for BiNem® manufacturing is based on using STN manufacturing process technologies since BiNem® and STN displays have a similar internal structure. The key differences between BiNem® and STN displays from a manufacturing point of view will be discussed. We show that industrial STN manufacturing equipment can be used to produce BiNem® LCDs at competitive costs. Reflective e‐book display modules with VGA resolution are produced in the pilot‐production series.     

Electro-elastic characteristics of asymmetric rectangular piezoelectric laminae

The electro-elastic characteristics of clamped rectangular piezoelectric laminated plates were analytically investigated. A fully covered electrode piezoelectric layer was laminated on an elastic layer to form a nonsymmetrical laminated plate. Using the electro-elastic theory with the Kirchhoff-Love hypothesis, formulation of analyses for mechanical, electrical, and electromechanical characteristics of the laminae are presented. Numerical analysis was carried out using the extended Kantorovich method to yield eigenvalues and eigenfunctions. Theoretical predictions of dynamic characteristics were validated by comparing results with finite element analysis data. The calculated natural frequencies are presented in easy-to-use figures that are useful for sensor and actuator design in microelectromechanical systems (MEMS).     

Resource brokering using a multi‐site resource allocation strategy for computational grids

Grid computing employs heterogeneous resources which may be installed on different platforms, hardware/software, computer architectures, and perhaps using different computer languages to solve large‐scale computational problems. As many more Grids are being developed worldwide, the number of multi‐institutional collaborations is growing rapidly. However, to realize Grid computing's full potential, it is expected that Grid participants must be able to share one another's resources. This paper presents a resource broker that employs the multi‐site resource allocation (MSRA) strategy and the dynamic domain‐based network information model that we propose to allocate Grid resources to submitted jobs, where the Grid resources may be dispersed at different sites, and owned and governed by different organizations or institutes. The jobs and resources may also belong to different clusters/sites. Resource statuses collected by the Ganglia, and network bandwidths gathered by the Network Weather Service, are both considered in the proposed scheduling approach. A dynamic domain‐based model for network information measurement is also proposed to choose the most appropriate resources that meet the jobs' execution requirements. Experimental results show that MSRA outperformed the other tested strategies. Copyright © 2010 John Wiley & Sons, Ltd.