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排序方式: 共有6226条查询结果,搜索用时 15 毫秒
41.
Shye Lin Wu Chung Len Lee Tan Fu Lei Chen C.F. Chen L.J. Ho K.Z. Ling Y.C. 《Electron Device Letters, IEEE》1994,15(4):120-122
In this study, it is demonstrated that the incorporation of fluorine can enhance poly-Si/Si interfacial oxide break-up in the poly-Si emitter contacted p+-n shallow junction formation. The annealing temperature for breaking up the poly-Si/Si interfacial oxide has been found to be as low as 900°C. As a result, the junction depth of the BF2-implanted device is much larger than that of the boron-implanted device 相似文献
42.
Tahui Wang Chimoon Huang Chou P.C. Chung S.S.-S. Tse-En Chang 《Electron Devices, IEEE Transactions on》1994,41(9):1618-1622
A two-dimensional numerical simulation including a new interface state generation model has been developed to study the performance variation of a LDD MOSFET after a dc voltage stress. The spatial distribution of hot carrier induced interface states is calculated with a breaking silicon-hydrogen bond model. Mobility degradation and reduction of conduction charge due to interface traps are considered. A 0.6 μm LDD MOSFET was fabricated. The drain current degradation and the substrate current variation after a stress were characterized to compare the simulation. A reduction of the substrate current at Vg ≃0.5 Vd in a stressed device was observed from both the measurement and the simulation. Our study reveals that the reduction is attributed to a distance between a maximum channel electric field and generated interface states 相似文献
43.
A low frequency, injected beam, circular format crossed-field amplifier has been designed and constructed for the purpose of studying electron-radio frequency wave interaction in reentrant devices. The device has been designed to allow in situ diagnostic probe measurements in the space between the anode and sole. The device has been operated in nonreentrant, fully reentrant, and reentrancy controlled configurations. Details of the design and operating parameters are described. Device characteristics are examined with respect to the amount of circulating charge or degree of reentrancy. A large increase in gain has been achieved from nonreentrant to the fully reentrant format. A gain of 7.2 dB has been obtained for the latter whereas only 3.8 dB has been obtained for the former with 30 mA of injected beam current. A maximum gain of 14.4 dB has been achieved for the fully reentrant configuration. Electron beam and noise measurements versus the degree of reentrancy have also been examined. Results from the nonreentrant amplifier performance have been directly compared with the MASK simulation code and good agreement has been obtained. These experiments will provide the basis for more detailed investigations on the effect of reentrancy on CFA operation and will also allow for the development of more accurate computer models of the reentrant system for numerical simulation of CFA operation 相似文献
44.
Measurement and modeling of self-heating in SOI nMOSFET's 总被引:4,自引:0,他引:4
Su L.T. Chung J.E. Antoniadis D.A. Goodson K.E. Flik M.I. 《Electron Devices, IEEE Transactions on》1994,41(1):69-75
Self-heating in SOI nMOSFET's is measured and modeled. Temperature rises in excess of 100 K are observed for SOI devices under static operating conditions. The measured temperature rise agrees well with the predictions of an analytical model and is a function of the silicon thickness, buried oxide thickness, and channel-metal contact separation. Under dynamic circuit conditions, the channel temperatures are much lower than predicted from the static power dissipation. This work provides the foundation for the extraction of device modeling parameters for dynamic operation (at constant temperature) from static device characterization data (where temperature varies widely). Self-heating does not greatly reduce the electromigration reliability of SOI circuits, but might influence SOI device design, e.g., requiring a thinner buried oxide layer for particular applications and scaled geometries 相似文献
45.
Pd-Ge based ohmic contact to n-GaAs with a TiW diffusion barrier was investigated. Electrical analysis as well as Auger electron
spectroscopy and the scanning electron microscopy were used to study the contact after it was subjected to different furnace
and rapid thermal annealing and different aging steps. All analyses show that TiW can act as a good barrier metal for the
Au/Ge/Pd/n-GaAs contact system. A value of 1.45 × 10−6 Ω-cm2 for the specific contact resistance was obtained for the Au/TiW/Ge/Pd/n-GaAs contact after it was rapid thermally annealed
at 425°C for 90 s. It can withstand a thermal aging at 350°C for 40 h with its ρc increasing to 2.94 × 10−6Ω-cm2 and for an aging at 410°C for 40 h with its ρc increasing to 1.38 × 10−5 Ω-cm2. 相似文献
46.
Resilient metal spring silicone-matrix conducting composites for separable interconnections in electronics were fabricated
by the impregnation of silicone into a preform comprising randomly oriented C-shaped Cu-Be springs and a small proportion
of Sn-Pb solder, which served to connect the springs at some of their intersections. Composites containing 6.1-9.8 vol.% total
filler exhibited volume electrical resistivity 0.5-1.0 mΩ.cm and contact resistivity (with copper) 11-17 mΩ.cm2. A compressive stress of about 30 kPa was needed for the low contact resistivity to be reached. The volume 17-26% and the
contact resistivity increased by 5% after heating in air at 130-150°C for seven days. Composites containing <9 vol.% total
filler showed no stress relaxation for seven days at 6.0% strain. 相似文献
47.
48.
Kuo-Liang Chung Lung-Chun Chang 《IEEE transactions on image processing》2003,12(6):648-652
According to the observation on the distribution of motion differentials among the motion vector of any block and those of its four neighboring blocks from six real video sequences, this paper presents a new predictive search area approach for fast block motion estimation. Employing our proposed simple predictive search area approach into the full search (FS) algorithm, our improved FS algorithm leads to 93.83% average execution-time improvement ratio, but only has a small estimation accuracy degradation. We also investigate the advantages of computation and estimation accuracy of our improved FS algorithm when compared to the edge-based search algorithm of Chan and Siu (see IEEE Trans. Image Processing, vol.10, p.1223-1238, Aug. 2001); experimental results reveal that our improved FS algorithm has 74.33% average execution-time improvement ratio and has a higher estimation accuracy. Finally, we further compare the performance among our improved FS algorithm, the three-step search algorithm, and the block-based gradient descent search algorithm. 相似文献
49.
M.H. Song B. Park S. Nishimura T. Toyooka I.J. Chung Y. Takanishi K. Ishikawa H. Takezoe 《Advanced functional materials》2006,16(14):1793-1798
A liquid crystal (LC) photonic device with an anisotropic optical heterojunction structure has been fabricated. The device has a phase‐retarding nematic LC (NLC) layer sandwiched between two polymer cholesteric LC films with right‐handed helices of different pitches. Electrotunable non‐reciprocal light transmittance and unidirectional circularly polarized (CP) lasing emission have been successfully demonstrated for this device structure. Two left CP (LCP) lasing emission peaks are observed at the edges of the overlapping region between the two photonic bands in the structure and are shifted upon the application of a voltage. In contrast, a non‐reciprocal right CP (RCP) lasing emission peak emerges at one of the band edges and diminishes upon the application of a voltage. These phenomena are interpreted based on the selective reflection of RCP light and the reorientation of the NLC molecules by the application of a voltage. 相似文献
50.
The notion of pseudorandomness is the theoretical foundation on which to consider the soundness of a basic structure used in some block ciphers. We examine the pseudorandomness of the block cipher KASUMI, which will be used in the next‐generation cellular phones. First, we prove that the four‐round unbalanced MISTY‐type transformation is pseudorandom in order to illustrate the pseudorandomness of the inside round function FI of KASUMI under an adaptive distinguisher model. Second, we show that the three‐round KASUMI‐like structure is not pseudorandom but the four‐round KASUMI‐like structure is pseudorandom under a non‐adaptive distinguisher model. 相似文献