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41.
This paper presents a behavioral model that can be used to improve the manufacturability of systems based on MEMS convective sensors. This model permits to handle faults related to process scattering, taking into account not only the electrical and lateral geometrical parameters but also the influence of the cavity depth. Moreover correlations between conductive and convective phenomena are included. The model is validated with respect to FEM simulations and a very good agreement is obtained between the behavioral model and FEM results. The proposed model can then be used in system-level simulations, for instance to evaluate the impact of process scattering on the performances of the sensing part and/or to investigate different design and calibration strategies with respect to the system robustness.  相似文献   
42.
Highly reliable nitride-based LEDs with SPS+ITO upper contacts   总被引:1,自引:0,他引:1  
Nitride-based blue light emitting diodes (LEDs) with an n/sup +/-short period superlattice (SPS) tunnel contact layer and an indium tin oxide (ITO) transparent contact were fabricated. Compared with conventional nitride-based LEDs with Ni/Au upper contacts, it was found that we could achieve a 60% increase in electroluminescence (EL) intensity by using ITO upper contacts. However, it was also found that the lifetime of ITO LEDs were much shorter. Furthermore, it was found that we could achieve a longer lifetime and a smaller reverse leakage current (I/sub R/) by the deposition of a SiO/sub 2/ layer on top of the ITO LEDs.  相似文献   
43.
An encoder-dependent video cut detection algorithm is proposed. Based on the inertia property of natural videos, the proposed algorithm detects video cuts in the video-coding loop by making use of the intermediate results of video compression. Experiments show that the detection performance of the proposed algorithm is quite good as compared to previous works, and when it is integrated with the coder, not only is the content accessibility of the output code stream improved but also the compression ratio is improved. The authors regard this inertia-based algorithm as a step towards the integration of video compression and content-based video retrieval.  相似文献   
44.
介绍了用于钨双嵌入和钨栓CMP工艺的新型CMP3200TM氧化铝浆料,测试证明,这种浆料在110nm技术节点的钨CMP工艺应用中取得了理想的效果。通过对氧化铝粒子制造工艺的有效控制,获得了可满足110nm技术节点双嵌入和栓层钨CMP工艺要求的低缺陷率,高性价比的氧化铝蛐硝酸铁浆料。从而在价格竞争激烈的半导体制造领域,特别是代工市场引起了业界越来越多的关注。  相似文献   
45.
In this paper, a new method for autotuning of a phase-lead controller for nonselfregulating or integrating systems is proposed. By connecting the system with a suitable high-order derivative filter and a relay with hysteresis, the frequency data of the system can be obtained and phase-lead controllers can be designed based on some phase margin specifications. Simulations and experimental studies are included in the paper to illustrate the performance of the proposed algorithm  相似文献   
46.
47.
Investigation of interface traps in LDD pMOST's by the DCIV method   总被引:1,自引:0,他引:1  
Interface traps in submicron buried-channel LDD pMOSTs, generated under different stress conditions, are investigated by the direct-current current-voltage (DCIV) technique. Two peaks C and D in the DCIV spectrum are found corresponding to interface traps generated in the channel region and in the LDD region respectively. The new DCIV results clarify certain issues of the underlying mechanisms involved on hot-carrier degradation in LDD pMOSTs. Under channel hot-carrier stress conditions, the hot electron injection and electron trapping in the oxide occurs for all stressing gate voltage. However, the electron injection induced interface trap spatial location changes from the LDD region to the channel region when the stressing gate voltage changes from low to high  相似文献   
48.
The linkage-spring model based on a quasi-static looping has been used to determine the design rules to reduce the loop heights and the sagging altitude of gold wire in the package. In order to further simulating the capillary trajectory which includes a looping speed factor from the first bond to the second bond stages, a linkage-spring model is modified in this study. The factors of the inertia mass and variations in material properties with different strain-rates need to be considered due to a high speed looping.It is found that the looping speed effects on the wirebond profiles due to the inertia mass can be neglected at a regular looping process of 3–5g acceleration even up to around 10g acceleration. However, variations in the material properties during deformation at different strain-rates could be an important factor on the wirebond profiles. Fortunately, a pure annealed state like pure gold wire would be little strain-rate sensitivity. The effects of the strain-rate in pure gold wire, therefore, can be excluded in analysis. Accordingly, a linkage-spring model based on the quasi-static looping is still applicable in analyzing the wirebond profiles.  相似文献   
49.
The pedagogical product presented below is a practical work intended to the electrical engineering students, fourth year, of the National Institut of Applied Sciences of Rennes. This work is a part of filter realisation programme either in microstrip technology or lumped element. The aim of this practical work is restricted to calculate by optimizing all the basic parameters of the filter realization. Thus, an optimization and simulation work is performed on computer, by using a Touchstone software product of the Electronic Engineering Software society, to obtain parameter values close to the wished ones. This practical work is performed by groups of two students during three hours.  相似文献   
50.
The authors present the design and the development of integrated microwave filters using suspended substrate microstrip, a technology that provides many advantages. Through quasi-static approximation the propagation structure has been treated using integral equations solved with the method of moments. Thanks to this tool of analysis and to an accurate synthesis method, a series of bandpass filters have been designed and manufactured. The results presented validate the accuracy of our design method.  相似文献   
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