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The deterioration or catastrophic breakdown of thin gate oxides during ion implantation is studied. The effect of ion beam density, the distribution of the gate oxide deterioration over a wafer, and the effect of photoresist coverage are shown quantitatively by measuring the number of interface states generated in MOS capacitors. It is shown that the four charge sources contribute to the deterioration of gate oxide: the irradiated ion beam, the secondary electrons emitted from the gate electrode, the charges accumulated on the photoresist surface around the gate electrode, and the secondary electrons emitted from a wafer holder. The first three charges accelerate the deterioration of the gate oxide and the last one reduces it. A model of the gate oxide deterioration in ion implantation that is very useful for finding methods of reducing the charging damage is presented 相似文献
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W Kimura I Han Y Furukawa E Sunami N Futakawa T Inoue H Shinkai B Zhao T Muto M Makuuchi H Komatsu 《Canadian Metallurgical Quarterly》1997,44(14):387-393
Long-term survival of carcinomas in the body and tail of the pancreas after surgery is still rare. One of the major reasons for unresectability is cancerous invasion to major vessels, such as the common hepatic and splenic arteries. Resection of the involved arteries can increase resectability and thus might increase post-operative survival. The aim of this study was to clarify the importance of the Appleby operation for carcinoma of the body and tail of the pancreas. A Case Report was carried out with a 54 year-old man, had suffered back pain and loss of body weight for six months. Imaging procedures such as US, CT or angiography showed a carcinoma in the body of the pancreas, about 3 cm in size, and both the common hepatic and splenic arteries were invaded by the tumor. The Appleby operation was used for this patient, since firstly there was no invasion to the head of the pancreas, secondly neither the proper hepatic artery nor the SMA was involved, thirdly the root of the CA was free of carcinoma, and finally because clear pulsation of the proper hepatic artery could be felt one or two minutes after occlusion of the CHA, which indicated that resection of the CHA would not lead to hepatic ischemia. The postoperative course was uneventful. His appetite recovered well and his body weight increased to the level before the disease. The patient was relieved from back pain and has returned to work 18 months after the operation, although he had a local recurrence eight months after the operation. In addition, eleven cases with carcinoma of the body and tail of the pancreas were used for a literature review. The average survival time after the Appleby operation is 6.6 months, and four patients are still alive. One patient has survived 13 years after the operation. It was concluded that although the prognosis after Appleby procedure is still not satisfactory that this operation can at least offer patients a better quality of life. 相似文献
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Pulsed laser annealing was carried out for n-type semiconducting GaAs in air, 1 bar nitrogen, 1 bar argon, and 100 bar argon gas ambiences. Depth profiles of the atomic ratio
measured by SIMS indicate that pulse annealing in air results in As loss and penetration of oxygen into the crystal, both of which affect dopant redistribution and deteriorate electrical properties of the annealed layer. High electrical activity (100%) and electron mobilities were achieved for high-dose implants of Si+ (1 × 1015 cm−2) by pulsed laser annealing in the high-pressure ambience. 相似文献
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Fumio Fujii 《International journal for numerical methods in engineering》1981,17(12):1843-1859
For plate bending analysis, both discrete and non-discrete mixed methods are presented by using spline functions in the Hellinger-Reissner variational principle. Piecewise spline interpolation with local supports and overall spline interpolation with boundary knots are applied to each of two mixed functionals. The prescribed boundary conditions can be considered by multiple boundary knots. The convergence behaviour of the mixed methods presented is studied. Numerical examples show that a high degree of accuracy can be obtained due to continuous properties in the high derivatives of the employed shape functions. The proposed mixed methods are found to be very competitive with other numerical methods for plate bending problems. 相似文献
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Khan JS Imamoto Y Yamazaki Y Kataoka M Tokunaga F Terazima M 《Analytical chemistry》2005,77(20):6625-6629
A new type of biosensor is presented for the first time. This method is based on the diffusion measurement in the time domain by the transient grating method. As the first demonstration of this new method, various intermolecular interactions with a reaction intermediate of photoactive yellow protein, such as the protein-protein interaction, protein-DNA interaction, and protein-small molecule binding are detected. The characteristic advantages and limitations are summarized. 相似文献