共查询到20条相似文献,搜索用时 62 毫秒
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采用锌粉和银粉为蒸发源,用热蒸发法不同温度下制备了四针状纳米氧化锌,并以单独的锌粉做对照。采用扫描电子显微镜(SEM)观察其形貌,X射线衍射(XRD)谱表征其晶体结构。采用丝网印刷方法将其制备为场致电子发射阴极,将阴极与印刷有荧光粉的阳极板组装成二极结构场致发射显示屏,并进行了场致电子发射特性对比实验。结果表明较高温度制备的氧化锌具有较好的场致发射性能;掺杂银粉的蒸发源制备的样品的发射性能明显优于没有掺杂银粉的样品。实验证明ZnO是一种优良的场致发射冷阴极材料,在真空电子方面具有广阔的应用前景。 相似文献
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碳纳米管场发射显示器的研究进展 总被引:14,自引:6,他引:8
碳纳米管因具有良好的电子发射特性而成为理想的场发射阴极材料,利用碳纳米管作阴极的场致发射平板显示器件的研究是目前显示技术领域的研究热点之一。报道了场发射显示器(FED)的结构及工作原理、阴极发射材料应具有的特点及碳纳米管在场发射领域中的应用情况。详细地论述了碳纳米管的场致发射特性,包括开启电场、发射电流密度、电流稳定性及发射点密度等,对国内外碳纳米管场发射显示器的发展现状及趋势作了回顾和展望,并对目前所面临的主要问题作了分析,同时提出了一些改进的思路。 相似文献
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三极场发射显示器中二次印刷型碳纳米管阴极的制备及特性(英文) 总被引:2,自引:2,他引:0
结合丝网印刷技术,研发了一种碳纳米管阴极制备法.利用双壁纳米管作为原材料,并加入细小银颗粒,制作了混合纳米管浆料.将混合纳米管浆料制作在传导电极表面,再将普通纳米管浆料印刷在混合纳米管浆料的上面.在链式烧结炉中对烘烤后的纳米管浆料同时进行烧结以除掉有机溶剂.在进行适当的后处理工艺之后,就形成了二次印刷型纳米管阴极,它能显著改善阴极的场致发射特性.制作了二次印刷型纳米管阴极的三极结构场致发射显示器.该显示器具有更高的发光亮度以及更好的发光图像亮度均匀性.与普通纳米管阴极场致发射显示器相比较,它能够将开启电场从2.15V/μm降低到1.75V/μm,并能够将最大场发射电流从735.8μA提高到1 588.5μA.所研发的纳米管阴极制备方法具有很强的实际应用性,且制作成本低廉. 相似文献
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在强电场条件下,由阴极通过场致发射产生的电子具有很强的空间电荷效应,因此真空二极管的空间电荷限制电流是设计高功率微波源等强流电子束器件时需要考虑的重要参数.场致发射电流密度只和阴极材料、阴极表面电场等有关,而空间电荷效应则会受二极管电压、间隙距离等因素的影响.为研究二极管间隙距离对场致发射过程中空间电荷效应的影响,建立了由场致发射阴极构成的一维平板真空二极管物理模型,利用第一性原理的粒子模拟方法,研究了二极管间隙距离和外加电压等参数变化时的阴极表面电场随时间的演变特性,得到了阴极表面稳态电场和二极管间隙距离之间的关系.结果表明,场致发射过程开始后,阴极表面电场先有个振荡过程,随后趋于稳定;在同一外加电场条件下,间隙距离越长,稳态电场的绝对值越小,且达到稳态所需的时间也越长;间隙距离越短,当阴极表面电场达到稳定状态时,二极管间隙区的电场分布变化越剧烈. 相似文献
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采用质点网格法(particle-in-cell),利用MAGIC软件模拟了场致发射的物理过程.对两 种典型的场致发射模型(Spindt阴极发射体和金刚石薄膜发射体)分别进行了模拟.对Spind t阴极发射,研究了发射特性与尖端尺寸,尖端与栅极面的相对高度的关系.对金刚石薄膜发 射,比较了三极管和四极管的发射特性,以及薄膜面积对发射特性的影响,得出金刚石薄膜 发射体优于Spindt发射体的特性.
关键词:
场致发射
MAGIC程序
Spindt发射体
金刚石薄膜发射体 相似文献
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三极结构四针状纳米ZnO场致发射显示器的研究 总被引:2,自引:0,他引:2
针对二极式场致发射显示器(field emission display, FED)驱动电压过高的问题, 设计制作了前栅极式三极结构纳米ZnO场致发射显示器, 并进行了场致发射实验, 验证这种结构的可行性.前栅极结构采用喷砂工艺结合光刻技术, 制作出微细的栅孔结构, 实现了较低电压的控制.同时对影响场致发射性能的栅极电压、栅孔开口尺寸和介质层厚度进行了分析讨论.实验结果表明:采用三极结构四针状纳米ZnO场致发射显示器具有良好的发射性能, 是一种有前途的场致发射显示器. 相似文献
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本文采用热化学气相沉积方法制备氧化锌纳米线阵列, 研究氧化锌纳米线阵列在紫外光辐照下的场电子发射特性. 实验结果表明, 在紫外光辐照下, 氧化锌纳米线场发射开启电压降低, 发射电流明显增大. 机理分析认为, 氧化锌纳米线紫外光增强的场发射源自场电子发射与半导体耦合作用, 紫外光激发价带电子跃迁到导带和缺陷能级使发射电子数量增加, 同时, 光生电子发射降低了发射材料表面的有效功函数, 从而显著增强场电子发射性能. 氧化锌纳米线具有紫外光耦合增强场电子发射特性, 在光传感、冷阴极平板显示和场发射电子源等方面具有潜在的应用价值. 相似文献
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Chen Hong-sheng Qi Jun-jie Zhang Yue Liao Qing-liang Huang Yun-hua 《Frontiers of Physics in China》2007,2(2):195-198
The direct growth of a tetrapod-like ZnO nanostructure has been accomplished by using a thermal oxidation method without any
catalysts. Studies on the field emission properties of the ordered ZnO nanotetrapods films found that the shape of the ZnO
nanotetrapods has considerable effect on their field emission properties, especially the turn-on field and the emission current
density. Compared with the rod-like legs ZnO nanotetrapods, the nanotetrapods with acicular legs have a lower turn-on field
of 2.7 V/μm at a current density of 10 μA/cm2, a high field enhancement factor of 1830, and an available stability. More importantly, the emission current density reached
1 mA/cm2 at a field of 4.8 V/μm without showing saturation. The results could be valuable for using the ZnO nanostructure as a cold-cathode
field-emission material.
相似文献
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Long Zhao Yuxiang Chen Yuanming Liu Guofu Zhang Juncong She Shaozhi Deng Ningsheng Xu Jun Chen 《Current Applied Physics》2017,17(1):85-91
Addressable field emitter arrays (FEAs) have important applications in vacuum electronic devices. However, it is important to integrate nanowire emitters into a gated structure without influencing the device structure and maintain the excellent field emission properties of nanowire emitters in the FEAs after the fabrication process. In this study, gate-structure ZnO nanowire FEAs were fabricated by a microfabrication process. The structure combines a planar gate and an under-gate, which is compatible with the preparation of ZnO nanowire emitters. The effect of electrode materials on the field emission properties of ZnO nanowires was studied using a diode structure, and it was found that ZnO nanowire pads on indium-tin-oxide (ITO) electrode showed better field emission performance compared with chromium (Cr) electrode. In addition, effective emission current modulation by the gate voltage was achieved and the addressing capability was demonstrated by integrating the ZnO nanowire FEAs in a vacuum-encapsulated field emission display. The reported technique could be a promising route to achieve large area addressable FEAs. 相似文献
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采用简单物理气相沉积法制备出取向和非取向的氧化锌纳米棒,他们的场致电子发射性能测量结果表明,ZnO纳米棒具有较好的场发射性能,但是高度取向的ZnO纳米棒阵列并不利于获得高的场致电子发射电流密度.这可能是由于高密度ZnO纳米棒之间具有较高的屏蔽效应,降低了ZnO纳米棒阵列的场放大因子,从而影响了其场发射性能.相反,非取向ZnO纳米棒由于相互之间的屏蔽效应比较弱,而且表面存在容易成为发射中心的微小突起,表现出较好的场发射效果.这些结果不仅有助于加深我们对准一维纳米材料场致电子发射性能的理解,也为未来场发射电子器件的实际应用提供了可靠的依据.
关键词:
氧化锌
场发射
非取向 相似文献
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J. Li G.J. Fang C. Li L.Y. Yuan L. Ai N.S. Liu D.S. Zhao K. Ding G.H. Li X.Z. Zhao 《Applied Physics A: Materials Science & Processing》2008,90(4):759-763
Wurtzite stalactite-like quasi-one-dimensional ZnS nanoarrays with ZnO protuberances were synthesized through a thermal evaporation
route. The structure and morphology of the samples are studied and the growth mechanism is discussed. X-ray diffraction (XRD)
results show both the ZnS stem and the ZnO protuberances have wurtzite structure and show preferred [001] oriented growth.
The photoluminescence and field emission properties have also been investigated. Room temperature photoluminescence result
shows it has a strong green light emission, which has potential application for green light emitter. Experimental results
also show that the stalactite arrays have a good field emission property, with turn-on field of 11.4 V/μm, and threshold field
of 16 V/μm. The ZnO protuberances on the ZnS stem might enhance the field emission notably.
PACS 81.05.Dz; 81.07.Bc; 81.16.-c; 78.60.Hk; 85.45.Db 相似文献
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Vertical ZnO nanoneedles with sharp tips are secondarily grown on tips of primarily grown ZnO micropyramids by a vapour transport process. The field emission (FE) properties exhibit a lower turn-on electric field and a higher field enhancement factor as compared with vertical ZnO microrods. This result indicates that ZnO nanoneedles have good optimum shapes for FE due to electron accumulation at sharp tips. 相似文献
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利用水热法制备了垂直于衬底的定向生长的ZnO纳米棒,利用扫描电子显微镜及光致发光的方法对其形貌及光学特性进行了表征,利用场发射性能测试装置对ZnO纳米棒的场发射性能进行了测试.结果表明:利用水热法在较低的温度(95 ℃) 下生长了具有较好形貌和结构的ZnO纳米棒,并表现出了较好的场发射特性,当电流密度为1 μA/cm2时,开启电场是2.8 V/μm,当电场为6.4 V/μm时,电流密度可以达到0.67 mA/cm2,场增强因子为3360.稳定性测试表明,在5 h内,4.5 V/μm的电场下,其波动不超过25%.将制备的ZnO纳米棒应用到有机/无机电致发光中,其中ZnO纳米棒为电子传输层,m-MTDATA(4,4',4″-tris{N,(3-methylphenyl)-N-phenylamino}-triphenylamine) 为空穴传输层,得到了ZnO的342 nm的紫外电致发光,此发光较ZnO纳米棒光致发光的紫外发射有约40 nm的蓝移.
关键词:
ZnO纳米棒
场发射
水热法
有机/无机复合电致发光 相似文献
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Surface coating effect on field emission performance of ZnO nanowires was studied by zinc surface coating. Coating time was
found to play an important role in determining the field emission properties. 3 s and 5 s coating enhanced the field emission
properties considerably, with lower turn-on field and larger electron emission current density. Prolonging the coating time
to 10 s deteriorated the field emission properties of ZnO nanowires. Surface morphology change and green emission in photoluminescence
related surface state were found to be responsible for such improvement. Our results provide an innovative approach to improve
the field emission properties of ZnO nanowires for development of vacuum nanoelectronic devices. 相似文献