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991.
O.V. TretyakV.A. Skryshevsky V.A. VikulovYu.V. Boyko V.M. Zinchuk 《Thin solid films》2003,445(1):144-150
The character of electronic states in porous silicon (PS)-Si, Pd-PS interfaces, and/or PS bulk at the formation of the metal-PS-silicon heterostructure was studied. The energy parameters were estimated using the deep-level transient spectroscopy and capacitance-voltage characteristics at the accounting of the voltage drop distribution along the structure. The analytical expression for voltage drop distribution along dielectric layer, porous layer and space charge region in silicon was obtained by solving the equation for continuity of the electrostatic induction vector. The electronic states studied were shown to manifest the quasi-continuous sub-band in the energy gap if the porous layer was 30-nm thick. Their density increased, as the energy position was being transformed to a deeper energy level of Ev+0.81 eV at the PS layer growing to 90 nm wide. 相似文献
992.
Noise modeling for RF CMOS circuit simulation 总被引:2,自引:0,他引:2
Scholten A.J. Tiemeijer L.F. van Langevelde R. Havens R.J. Zegers-van Duijnhoven A.T.A. Venezia V.C. 《Electron Devices, IEEE Transactions on》2003,50(3):618-632
The RF noise in 0.18-/spl mu/m CMOS technology has been measured and modeled. In contrast to some other groups, we find only a moderate enhancement of the drain current noise for short-channel MOSFETs. The gate current noise on the other hand is more significantly enhanced, which is explained by the effects of the gate resistance. The experimental results are modeled with a nonquasi-static RF model, based on channel segmentation, which is capable of predicting both drain and gate current noise accurately. Experimental evidence is shown for two additional noise mechanisms: 1) avalanche noise associated with the avalanche current from drain to bulk and 2) shot noise in the direct-tunneling gate leakage current. Additionally, we show low-frequency noise measurements, which strongly point toward an explanation of the 1/f noise based on carrier trapping, not only in n-channel MOSFETs, but also in p-channel MOSFETs. 相似文献
993.
994.
V. P. Uvarov 《Glass and Ceramics》2003,60(11-12):359-360
A method for constructing experimental models of drawing optical rods based on experimental data is considered. The models obtained make it possible to identify admissible technological parameter fluctuations in the range selected. 相似文献
995.
996.
V. V. Vavilova V. M. Ievlev A. P. Isaenko Yu. E. Kalinin Yu. K. Kovneristyi N. A. Palii B. G. Sukhodolov V. N. Timofeev 《Inorganic Materials》2003,39(1):72-76
The effect of pulsed photon annealing with energy densities from 1.4 to 42 J/cm2 for various lengths of time on the structure of the amorphous alloy Fe79P14.2Si4.4Mn2.2V0.2 was studied by x-ray diffraction, differential scanning calorimetry, and transmission electron microscopy. The results demonstrate that short-term irradiation with low energy densities leads to surface relaxation of the amorphous alloy, increases the strength of the surface layer, and reduces the internal-friction peak. Longer term photon annealing leads to crystallization of the alloy throughout the sample thickness. 相似文献
997.
998.
999.
Claesson V. Lonn H. Suri N. 《Parallel and Distributed Systems, IEEE Transactions on》2004,15(8):725-739
A desired attribute in safety-critical embedded real-time systems is a system time and event synchronization capability on which predictable communication can be established. Focusing on bus-based communication protocols, we present a novel, efficient, and low-cost start-up and restart synchronization approach for TDMA environments. This approach utilizes information about a node's message length that forms a unique sequence to achieve synchronization such that communication overhead can be avoided. We present a fault-tolerant initial synchronization protocol with a bounded start-up time. The protocol avoids start-up collisions by deterministically postponing retries after a collision. We also present a resynchronization strategy that incorporates recovering nodes into synchronization. 相似文献
1000.
The development of hydrogen power for switching the most energy-intensive segments of industry and transportation to a qualitatively new energy carrier - hydrogen - as a strategic direction for decreasing the acuteness of the problems of environmental pollution and the growing shortage of petroluem-based fuel for automobiles is examined.It is concluded for vehicular transportation systems in megalopolises and large cities that the main solution is to develop an ecologically safe means of transportation powered by an electrochemical generator operating on hydrogen and atmospheric air. A preliminary conclusion is drawn on the basis of a comparison of various types of electrochemical generators that electrochemical generators with a solid-polymer membrane have merit.Various systems for storing hydrogen in an automobile are examined. The system which is closest to practical implementation is a system for storing hydrogen gas at high pressure in a tank made of composite materials. An assessment is made of the danger that the hydrogen stored in a high-pressure tank in an automobile will catch fire or explode.Translated from Atomnaya Énergiya, Vol. 97, No. 5, pp. 380–387, November, 2004. 相似文献