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排序方式: 共有2197条查询结果,搜索用时 218 毫秒
1.
Ju-Hwan Han Jin-Myung Choi Seong-Hyeon Lee Woojin Jeon Jin-Seong Park 《Ceramics International》2018,44(17):20890-20895
Silicon nitride (Si3N4) films have received great attention not only as dielectric materials for the gate dielectric of transistors and the insulator of capacitors, but also as a buffer layer and etch-stop layer for the semiconductor industry. As the applications of Si3N4 film increase, the necessity of investigating a novel deposition process applicable at low temperature has emerged. In this regard, the plasma-enhanced atomic layer deposition (PEALD) technique is attractive as a promising process; however, the Si3N4 film deposition process at growth temperatures less than 150?°C using PEALD has not been investigated. In this work, the growth behavior and chemistry of SiNx (x?<?1.33) film deposited by the PEALD process at various growth temperatures were developed. Insufficient thermal energy from low growth temperature induces an unstable chemical state of deposited film due to the remaining unreacted ligand of adsorbed precursors. This state results in a further chemical reaction to SiO2 formation by air exposure. Other chemical effects depending on chemical composition and electrical property were also examined in detail. 相似文献
2.
Y.J. Han Y.Z. Wang C.H. Yang Q. Yao J. Chen S.F. Huang 《Ceramics International》2018,44(13):15153-15159
This work reports the characteristics of nonstoichiometric Na0.5+xBi0.5+yTi0.96W0.01Ni0.03O3 (x?=?0.0%, y?=?1.0%; x?=?0.5%, y?=?2.0%; x?=?1.0%, y?=?4.0%) ceramic films derived from chemical solution deposition and the role played by excess Na/Bi in modifying microstructure and electrical properties. Single perovskite phase structure can be maintained in all compositions. Decreased grain size can be obtained with the increasing compensation for volatile Na/Bi elements. Particularly, extra amounts of 0.5?mol% Na and 2.0?mol% Bi leads to reduced leakage and enhanced ferroelectric polarization. Meanwhile, due to the high breakdown electrical field strength and large difference between maximum and remanent polarization, an excellent energy storage performance can be achieved in Na0.505Bi0.52Ti0.96W0.01Ni0.03O3 sample, which is distinguished by a recoverable energy storage density of 40.5?J/cm3 and an energy storage efficiency of 43.6% at 2515?kV/cm as well as a good frequency stability. Hence, the regulation for the content of volatile elements is effective to modify the electrical response of Na0.5Bi0.5TiO3-based materials. 相似文献
3.
《Ceramics International》2020,46(4):4148-4153
The ferroelectric photovoltaic (FPV) effect obtained in inorganic perovskite ferroelectric materials has received much attention because of its large potential in preparing FPV devices with superior stability, high open-circuit voltage (Voc) and large short-circuit current density (Jsc). In order to obtain suitable thickness for the ferroelectric thin film as light absorption layer, in which, the sunlight can be fully absorbed and the photo-generated electrons and holes are recombined as few as possible, we prepare Pb0.93La0.07(Zr0.6Ti0.4)0.9825O3 (PLZT) ferroelectric thin films with different layer numbers by the sol-gel method and based on these thin films, obtain FPV devices with FTO/PLZT/Au structure. By measuring photovoltaic properties, it is found that the device with 4 layer-PLZT thin film (~300 nm thickness) exhibits the largest Voc and Jsc and the photovoltaic effect obviously depends on the value and direction of the poling electric field. When the device is applied a negative poling electric field, both the Voc and Jsc are significantly higher than those of the device applied the positive poling electric field, due to the depolarization field resulting from the remnant polarization in the same direction with the built-in electric field induced by the Schottky barrier, and the higher the negative poling electric field, the larger the Voc and Jsc. At a -333 kV/cm poling electric field, the FPV device exhibits the most superior photovoltaic properties with a Voc of as high as 0.73 V and Jsc of as large as 2.11 μA/cm2. This work opens a new way for developing ferroelectric photovoltaic devices with good properties. 相似文献
4.
Preparation and characterisation of films from xylose‐glycosylated peanut protein isolate powder 下载免费PDF全文
Wei‐Jing Lin Hong‐Zhi Liu Ai‐Min Shi Li Liu Benu Adhikari Qiang Wang 《International Journal of Food Science & Technology》2015,50(7):1538-1544
This work aimed at producing and characterising xylose‐glycosylated peanut protein isolate (PPI‐X) films by dissolving PPI‐X powder in water at ambient temperature and further plasticising with glycerol. The effect of powder dissolution temperature (20–100 °C) and glycerol concentration (15.0–45.0%, w/w) on mechanical properties and integrity of these films was quantified. The results showed that the powder dissolution temperature had no significant effect on the mechanical and water resistance properties of PPI‐X films within the temperature range tested. With increasing concentration of glycerol, the tensile strength and water resistance of PPI‐X films decreased and elongation increased. The films produced by dissolving the PPI‐X powder at 20 °C and plasticising with 25.0% glycerol had comparable mechanical properties and better water resistance compared to some other plant protein films plasticising with glycerol. The results suggested that PPI‐X films could potentially be used as biodegradable packaging materials. 相似文献
5.
Immobilized lipase catalyzed synthesis of n‐amyl acetate: parameter optimization,heterogeneous kinetics,continuous flow operation and reactor modeling 下载免费PDF全文
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在光固化光敏树脂成型过程中,聚四氟乙烯离型膜会在树脂液位的波动影响下发生变形,进而影响光固化制件的精度,因此需要减小离型膜在制件过程的变形量,确保其相对稳定。首先分析树脂液位变化,通过液位变化量,等效出树脂液波动带给离型膜的载荷,建立离型膜受力模型。然后基于离型薄膜的挠度变形理论,应用Ansys软件进行模拟研究,对不施加预应力和施加不同预应力作用下的离型膜变形结果分析,结果表明施加预应力有利于提高离型膜稳定性,且施加预应力为2. 645M Pa时离型膜受到树脂波动影响最小,位置精度变化在0. 01 mm。 相似文献
8.
通过新型的旋转芯棒薄膜吹塑设备制备了低密度聚乙烯(LDPE)/高密度聚乙烯(HDPE)复合薄膜,并研究了该设备模具流道环流协同作用对吹塑聚乙烯薄膜结构和性能的影响。结果表明,制备的聚乙烯薄膜呈现一种互锁片晶结构;芯棒转速的提高对聚乙烯薄膜样品的结晶度、片晶厚度也有一定增益作用,使得结晶更完善;聚乙烯薄膜的拉伸性能和撕裂性能随芯棒转速提高都有所提升,尤其是横向力学性能,横向拉伸性能最大提升幅度为25.75%,横向撕裂性能最大提升幅度为27.64%;同时,该技术实现了在不影响聚乙烯薄膜的纵向热收缩率的情况下,大幅提高其横向热收缩率,提升幅度可达128.41%。 相似文献
9.
Xunwang Shi Xiuhan Yu Caiwen Nie Fengji Li Sam Zhang 《Ceramics International》2021,47(15):21546-21553
Color films are widely used for visual effect as well as for their functional properties. To date, however, synthesizing thin films with desired color remains challenging. In this work, AlN color films are deposited on Si wafers by precise control of the deposition time for different thickness during reactive magnetron sputtering from an Al target in Ar/N2 atmosphere. The thickness, morphology, structure, composition and color index are carefully examined by field emission scanning electron microscopy, atomic force microscopy, grazing incidence X-ray diffraction, X-ray photoelectron spectrometry and colorimeter, respectively. As the film thickness changes from 57 nm to 165 nm, the film exhibits purple, indigo, blue, green, yellow, orange and red in color. These colors repeat in the same order when the thickness goes over 165 nm. Once the thickness exceeds 467 nm, overlapping of colors takes place. The mechanisms are elucidated. 相似文献
10.
Molecular dynamics simulation is employed to study the depletion behaviors of perfluoro-lubricants under scanning laser heating for heat-assisted magnetic recording hard disk drives. A partial lubricant near the substrate is irradiated by the laser beam to mimic nano-scale heat transfer from disk to lubricant. The lubricant surface morphology and thickness profiles are examined to reveal the dynamic depletion behaviors. The localized temperature evolution is also evaluated to illustrate the direction-dependent ridge formation around the depletion zone. In addition, the effects of laser power and film thickness on lubricant depletion are explored. Although evaporation is enhanced significantly at high laser powers or for lubricant with thickness around one monolayer, thermodiffusion is the primary mode of lubricant depletion under scanning laser heating. 相似文献