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排序方式: 共有1416条查询结果,搜索用时 31 毫秒
1.
Jeong-Soo Lee Yang-Kyu Choi Daewon Ha Balasubramanian S. Tsu-Jae King Bokor J. 《Electron Device Letters, IEEE》2003,24(3):186-188
The hydrogen annealing process has been used to improve surface roughness of the Si-fin in CMOS FinFETs for the first time. Hydrogen annealing was performed after Si-fin etch and before gate oxidation. As a result, increased saturation current with a lowered threshold voltage and a decreased low-frequency noise level over the entire range of drain current have been attained. The low-frequency noise characteristics indicate that the oxide trap density is reduced by a factor of 3 due to annealing. These results suggest that hydrogen annealing is very effective for improving device performance and for attaining a high-quality surface of the etched Si-fin. 相似文献
2.
A mechanism of soldering of an aluminum alloy die casting to a steel die is proposed. A soldering critical temperature is
postulated, at which iron begins to react with aluminum to form an aluminum-rich liquid phase and solid intermetallic compounds.
The liquid joins the die with the casting upon solidification. The critical temperature is determined by the elements in both
the casting alloy and the die material and is equal to the solidus temperature of the resulting alloy. The critical temperature
is used to predict the onset of die soldering, and the local liquid fraction is related to the soldering tendency. Experiments
have been carried out to validate the concept and to determine the critical temperature for die soldering in an iron-aluminum
system. Thermodynamic calculations are used to determine the critical temperature and soldering tendency for the cases of
pure aluminum and a 380 alloy in a steel mold. Factors affecting the soldering tendency are discussed, and methods for reducing
die soldering are suggested. 相似文献
3.
Liang Y.C. Wenjiang Zeng Pick Hong Ong Zhaoxia Gao Jun Cai Balasubramanian N. 《Electron Device Letters, IEEE》2002,23(12):700-703
In this letter, a concise process technology is proposed for the first time to enable the fabrication of good quality three-dimensional (3-D) suspended radio frequency (RF) micro-inductors on bulk silicon, without utilizing the lithography process on sidewall and trench-bottom patterning. Samples were fabricated to demonstrate the applicability of the proposed process technology. 相似文献
4.
Conversion of acrylonitrile-based precursors to carbon fibres 总被引:1,自引:0,他引:1
Mukesh K. Jain M. Balasubramanian P. Desai A. S. Abhiraman 《Journal of Materials Science》1987,22(1):301-312
The progress of stabilization of two compositions of acrylic fibres with various orientations has been followed by a variety of techniques. The thermooxidative treatments for stabilization have been carried out in a continuous process and also in a batch process under free shrinkage, constant length and constant tension conditions. The morphological model of acrylic fibres consists of an alternating sequence of laterally ordered and laterally disordered regions along the fibre direction. This structure is consistent with the observations based on small-angle X-ray scattering of copper- impregnated precursor fibres and thermomechanical response, thermal stress development, calorimetry, wide- and small-angle X-ray scattering and sonic modu-lus measured at different extents of stabilization. Lateral as well as orientational order in these fibres can be increased markedly through a high-temperature deformation process prior to stabilization. An increase in perfection and extent of order is observed in the early stages of stabilization. There is also a simultaneous decrease in the orientation of the disordered phase at this stage and the extent of this decrease depends on the axial constraints imposed on the fibre. Little difference in the rate of stabilization is observed as measured by density or oxygen uptake for fibres with different extents of orientation, lateral order or restraint. Fibres containing itaconic add, a stabilization catalyst did show an increased rate of stabilization. Inferences have been drawn regarding additional research pertaining to achieving high order in precursor fibres, minimizing orientational relaxation during oxidative stabilization, and the techniques for monitoring the extents of the stabilization treatment and the changes in relevant morphological parameters. 相似文献
5.
Becker-Gomez A. Lakshmi Viswanathan T. Viswanathan T.R. 《Circuits and Systems II: Express Briefs, IEEE Transactions on》2008,55(7):609-613
6.
Evolution of multiprotocol label switching 总被引:11,自引:0,他引:11
Multiprotocol label switching (MPLS) is rapidly emerging as an Internet Engineering Task Force (IETF) standard intended to enhance the speed, scalability, and service provisioning capabilities in the Internet. MPLS uses the technique of packet forwarding based on labels, to enable the implementation of a simpler high-performance packet forwarding engine. This also decouples packet forwarding from routing, facilitating the provision of varied routing services independent of the packet forwarding paradigm. The authors track the evolution of this technology in relation to other existing technologies. Then an overview of the MPLS architecture and design is provided. In addition, some of the work that was a precursor to MPLS is discussed, as well as related issues and debates 相似文献
7.
M. D. Kannan Sa. K. Narayandass C. Balasubramanian D. Mangalaraj 《Journal of Materials Science》1992,27(18):5040-5044
Aluminium-neodymium oxide-aluminium thin film capacitors have been prepared by thermal evaporation and the d.c. conduction properties of these films have been studied. The thicknesses of the films have been determined by a multiple beam interferometer. The current-voltage power-law dependence showed that the conduction in these films is space-charge limited. The linear dependence of the current density on the square root of the applied field confirmed the exponential trap distribution. The trap density has been found to be of the order of 1026 m–3. It has also been observed that the Schottky type of conduction is predominant in the high-field region and the height of the Schottky barrier has been determined. It is seen that the conduction mechanism is an activated process with the activation energy decreasing with increasing field. 相似文献
8.
OBJECTIVE: To determine the characteristics and long-term outcome of radiation-induced thyroid cancer in children. DESIGN: Retrospective review of a cohort of 4296 irradiated patients who received childhood radiation treatment to the head and neck area at the same hospital. PATIENTS: Forty-one children who were younger than 20 years when thyroid cancer developed in them and 77 adults in whom thyroid cancer developed. All 118 cases were diagnosed before 1974 and were followed up for a median of 19.4 years. RESULTS: Children presented with clinically palpable lymph nodes more often than adults (30.7% vs 15.1%, P = .05) and had more recurrences (39% vs 16%, P = .05). Despite these frequent recurrences, only one patient (an adult) died of thyroid cancer. Seventy percent of the recurrences occurred during the first 10 years of follow-up, but recurrences continued after 20 years. The adults had previously identified factors that predicted the risk of recurrences, but none could be identified in the children. CONCLUSION: The presentation and relatively good outcome of radiation-induced thyroid cancer in children is similar to that in nonirradiated children. Frequent and late recurrences call for lifelong follow-up. 相似文献
9.
S. Kar T. Searles E. Lee G. B. Viswanathan H. L. Fraser J. Tiley R. Banerjee 《Metallurgical and Materials Transactions A》2006,37(3):559-566
The development of a set of computational tools that permit microstructurally based predictions for the tensile properties
of commercially important titanium alloys, such as Ti-6Al-4V, is a valuable step toward the accelerated maturation of materials.
This paper will discuss the development of neural network models based on a Bayesian framework to predict the yield and ultimate
tensile strengths of Ti-6Al-4V at room temperature. The development of such rules-based model requires the population of extensive
databases, which in the present case are microstructurally based. The steps involved in database development include producing
controlled variations of the microstructure using novel approaches to heat treatments, the use of standardized stereology
protocols to characterize and quantify microstructural features rapidly, and mechanical testing of the heat-treated specimens.
These databases have been used to train and test neural network models for prediction of tensile properties. In addition,
these models have been used to identify the influence of individual microstructural features on the tensile properties, consequently
guiding the efforts toward development of more robust mechanistically based models. Based on the neural network model, it
is possible to investigate the influence of individual microstructural features on the tensile properties, and in certain
cases these dependencies can point toward unrecognized phenomena. For example, the apparently unexpected trend of increase
in tensile strength with increasing prior β-grain size has led to the determination of the pronounced role of the basketweave microstructure in strengthening these alloys,
especially in case of larger prior β grains.
This article is based on a presentation made in the symposium “Computational Aspects of Mechanical Properties of Materials,”
which occurred at the 2005 TMS Annual Meeting, February 13–17, 2005, in San Francisco, CA, under the auspices of the MPMD-Computational
Materials Science & Engineering (Jt. ASM-MSCTS) Committee. 相似文献
10.