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排序方式: 共有723条查询结果,搜索用时 46 毫秒
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Casse M. Thevenod L. Guillaumot B. Tosti L. Martin F. Mitard J. Weber O. Andrieu F. Ernst T. Reimbold G. Billon T. Mouis M. Boulanger F. 《Electron Devices, IEEE Transactions on》2006,53(4):759-768
Electron and hole mobility in HfO/sub 2//metal gate MOSFETs is deeply studied through low-temperature measurements down to 4.2 K. Original technological splits allow the decorrelation of the different scattering mechanisms. It is found that even when charge trapping is negligible, strong remote coulomb scattering (RCS) due to fixed charges or dipoles causes most of the mobility degradation. The effective charges are found to be located in the HfO/sub 2/ near the SiO/sub 2/ interface within 2 nm. Experimental results are well reproduced by RCS calculation using 7/spl times/10/sup 13/ cm/sup -2/ fixed charges at the HfO/sub 2//SiO/sub 2/ interface. We also discuss the role of remote phonon scattering in such gate stacks. Interactions with surface soft-optical phonon of HfO/sub 2/ are clearly evidenced for a metal gate but remain of second order. All these remote interactions are significant for an interfacial oxide thickness up to 2 nm, over which, these are negligible. Finally, the metal gate (TiN) itself induces a modified surface-roughness term that impacts the low to high effective field mobility even for the SiO/sub 2/ gate dielectric references. 相似文献
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Pediatric anxiety disorders are common illnesses that, if left untreated, may induce academic, family, and interpersonal problems. Cognitive-behavioral techniques and other psychotherapeutic interventions may be adequate for the treatment of most anxiety disorders. For patients with severe symptoms or for whom psychotherapeutic approaches are not adequate, medications are indicated. Among the available medications, the SSRIs are currently the first choice; however, other medications, such as the benzodiazepines and the TCAs, may be used alone or sometimes in combination with the SSRIs. Caution with respect to medication interactions and side effects is indicated. In particular, long-term side effects in these medications have not been well studied. 相似文献
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Separator materials suitable for use in industrial alkaline water electrolysers are surveyed, including both inorganic and organic materials. The properties which make asbestos diaphragms unsuitable for use above 100°C are also reviewed.In summary, potassium titanate and polyantimonic acid separator materials perform well in high-temperature alkali. Oxide-coated metallic diaphragms merit further attention. Polysulfone and polyphenylene sulfide polymers are promising, but will need definite improvement in their wettability. Asbestos stabilization by silicate electrolyte additions may be viable. 相似文献
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Probing a model of educational productivity in high school science with national assessment samples.
Walberg Herbert J.; Pascarella Ernest; Haertel Geneva D.; Junker Linda K.; Boulanger F. David 《Canadian Metallurgical Quarterly》1982,74(3):295
Tested a psychological theory of educational productivity and explored the usefulness of the National Assessment of Educational Progress data for secondary analysis for policy purposes. The science achievement scores of 3,049 17-yr-old students were regressed on indexes of their socioeconomic status, motivation, quality (of instruction), class (social psychological environment), homework, and home conditions. Findings indicate that all measures of these productivity factors are significant in ordinary multiple regression equations when controlled for one another and race and gender, and the equation coefficients conform closely in sign and magnitude to theoretical values derived from C. W. Cobb and P. H. Douglas's (1928) theory of national economic productivity. Under a stringent causal probe, however, class and didactic quality of instruction appear to be the only unequivocal and potentially manipulable causes of science learning in the data. (19 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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The toxic gases released by combustion/pyrolysis of wool include CO, HCN and four compounds containing sulphur. Animal test data suggest that the toxicity of the sulphur compounds is significant. Wool was pyrolysed and the gases were analysed by GC-MS. SO2 was the main sulphur-containing gas produced by flaming combustion in an oxygen-enriched atmosphere. In pyrolysis under various conditions COS was a major sulphur-containing product. Although it is a highly toxic gas, COS has not so far been reported by workers engaged in the toxicity of fire gases. It is suggested that analysis of COS be included in the analytical toxicology of sulphur-containing polymers. 相似文献
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