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131.
This paper presents a theoretical framework about interface states creation rate from Si-H bonds at the Si/SiO2 interface. It includes three mains ways of bond breaking. In the first case, the bond can be broken thanks to the bond ground state rising with an electrical field. In the two others cases, incident carriers will play the main role either if there are very energetic or very numerous but less energetic. This concept allows us physically modeling the reliability of MOSFET transistors, and particularly NBTI permanent part, and Channel Hot Carrier (CHC) to Cold Carrier (CCC) damage. Finally, the translation of these physical models into reliability spice models is discussed. These models pave the way to Design-in Reliability (DiR) approach which seeks to provide a quantitative assessment of reliability - CMOS device reliability in this case - at design stage thereby enabling judicious margins to be taken beforehand. 相似文献
132.
Tae Woo Kim Hana Yoo In Young Kim Hyung‐Wook Ha Ah Reum Han Jong‐San Chang Ji Sun Lee Seong‐Ju Hwang 《Advanced functional materials》2011,21(12):2301-2310
Manganese oxide nanocrystals are combined with aluminum oxide nanocrystals to improve their crystallinity via calcination without a significant increase of crystal size. A nanocomposite, consisting of two metal oxides, can be synthesized by the reaction between permanganate anions and aluminum oxyhydroxide keggin cations. The as‐prepared manganese oxide–aluminum oxide nanocomposite is X‐ray amorphous whereas heat‐treatment gives rise to the crystallization of an α‐MnO2 phase at 600 °C and Mn3O4/Mn2O3 and γ‐Al2O3 phases at 800 °C. Electron microscopy and N2 adsorption‐desorption‐isotherm analysis clearly demonstrate that the as‐prepared nanocomposite is composed of a porous assembly of monodisperse primary particles with a size of ~20 nm and a surface area of >410 m2 g?1. Of particular interest is that the small particle size of the as‐prepared nanocomposite is well‐maintained up to 600 °C, a result of the prevention of the growth of manganate grains through nanoscale mixing with alumina grains. The calcined nanocomposite shows very‐high catalytic activity for the oxidation of cyclohexene with an extremely high conversion efficiency of >95% within 15 min. The present results show that the improvement of the crystallinity without significant crystal growth is very crucial for optimizing the catalytic activity of manganese oxide nanocrystals. 相似文献
133.
戴孟良 《有色冶金设计与研究》2012,33(1):21-23
介绍韶冶在氧化物料对工厂生产经营和现场环境造成不利影响的条件下,通过设备、工艺两方面的研究,提高氧化物料处理能力,从而增强烧结工艺对原料的适应性,使干精矿含硫降低,烧结机产能大幅度提升,烧结块质量保持较高水平,年创效益约2 500万元。 相似文献
134.
《Particulate Science and Technology》2012,30(8):927-931
ABSTRACTMaterials based on bismuth(III) oxide are candidate to be used in optical and electronic devices because of their properties such as a variable band gap, photoconductivity, photoluminescence, high refractive index, and dielectric permittivity. These properties are dependent of several factors, e.g., present phases and crystal morphology. The microwave-assisted hydrothermal method (MAH) is a fast and efficient approach of synthesis to obtain semiconductor powders. However, the synthesis of monoclinic bismuth oxide (α-Bi2O3) with acicular morphology by MAH was not found in literature. In this paper, microcrystals of acicular α-Bi2O3 (monophasic) were successfully obtained by MAH using a synthesis temperature of 80°C for 0.5?h. X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron, and transmission electron microscopies showed the formation of a monoclinic structure (space group P21/c) with acicular morphology that grew along the [001] direction. The temperature and time necessary to synthetize acicular microcrystals were significantly lower than those found for acicular microcrystals obtained by conventional hydrothermal method. 相似文献
135.
136.
FENG Ying HUANG ShiHua KANG Kai & FENG YuGuang Institute of Optoelectronic Technology Beijing Jiaotong University Beijing China 《中国科学:信息科学(英文版)》2010,(1)
The influence of channel length on the performances of carbon nanotube field effect transistors(CNT-FETs) has been studied.Buffered oxide etching was used to remove approximately a 60 nm layer from the original 100 nm silicon dioxide layer,to thin the dielectric layer of the back gate.Channel length of the CNT-FETs was changed along with the etching process.The dependence of drain-source current on gate voltage was measured to analyze the performance of the CNT-FETs,including the transconductance,carrier mo... 相似文献
137.
ZnO单晶的KOH碱液法生长和表征 总被引:2,自引:1,他引:1
采用自发成核方法,以KOH碱液作助熔剂,在银、镍和铁坩埚中分别生长了透明、棕绿色和棕色的纤维锌矿氧化锌单晶。X射线衍射和电感耦合等离子体原子发射光谱分析表明:晶体的颜色与所含的杂质有关,这些杂质来源于所使用的坩埚。采用光致发光(photoluminescence,PL)光谱对所生长的晶体进行了表征,结果显示,从银坩埚中生长的氧化锌晶体质量较高,其室温下用325nm波长光激发的PL光谱显示381nm强的紫外发射峰。在此基础上,从200mL银坩埚中生长出了尺寸为φ3mm×34mm氧化锌晶体。 相似文献
138.
Kyungyea Park Deok‐Kyou Lee Byung‐Sung Kim Haseok Jeon Nae‐Eung Lee Dongmok Whang Hoo‐Jeong Lee Youn Jea Kim Jong‐Hyun Ahn 《Advanced functional materials》2010,20(20):3577-3582
Stretchable and transparent thin film transistors (TFTs) with intrisically brittle oxide semiconductors are built using a wavy structural configuration that can provide high flexibility and stretchability. After device fabrication procedures including high temperature annealing, the oxide semiconductor‐based TFT arrays can be transferred directly to plastic or rubber substrates, without an additional device process, using transfer printing methods. This procedure can avoid some of the thermal degradation problems associated with plastic or rubber substrates by separating them from the annealing procedure needed to improve the device performance. These design and fabrication methods offer the possibility of developing a new format of stretchable electronics. 相似文献
139.
Gd2O3-modified CeO2 particles are prepared by a solid-state reaction method, and are used to remove Pb(II) ions from aqueous solutions by a photoelectrodeposition. The UV–photocatalytic activity for Pb(II) ion removal of the Gd2O3-modified CeO2 is significantly higher than that of pure CeO2. A solid solution Gd0.1Ce0.9O1.95 phase coexisting with the CeO2 matrix phase shows a high ability of photoelectrodeposition for the Pb(II) ions removal, compared to the two-phases mixture of Gd2O3–CeO2. The high photocatalytic activity is also supported by a strong photoluminescence (PL) signal from the Gd0.1Ce0.9O1.95–CeO2. The high activity can be due to a formation of heterojunctions between p-type Gd0.1Ce0.9O1.95 and n-type CeO2, promoting transfer of photogenerated electron–hole pairs and efficiency restraining recombination of the charges. 相似文献
140.
Batteries: Enhanced Electrocatalysis via 3D Graphene Aerogel Engineered with a Silver Nanowire Network for Ultrahigh‐Rate Zinc–Air Batteries (Adv. Funct. Mater. 18/2017) 下载免费PDF全文