Spindt型真空微三极管按比例缩小的CE规则

本文根据恒定电场原理，提出了Ｓｐｉｎｄｔ型真空微三极管按比例缩小规则。研究指出，Ｓｐｉｎｄｔ型真空微三极管按比例缩小后，性能明显改进，工作电压降低。     

自对准栅场发射三极管的设计

对于场发射三极管，提高使用频率，增加跨导以提高增益是设计的关键。因此，本文在研究场发射三极管工作原理的基础上，重点分析了场发射三极管结构参数与电参数的关系，设计出了两种结构、四种尺寸的自对准栅场发射三极管单元结构参数，并对它们的性能进行了讨论。     

基于场发射三极管结构的离子轰击分析

离子轰击影响场致发射器件的稳定性和工作寿命。本文以碳纳米管场发射三极管结构为例模拟了气体—电子碰撞电离产生的正离子回轰阴极的全过程，对模型中的平面阴极受损的位置和程度进行了的分析；为了减小离子轰击的影响，在三极管中引入了第二栅极利用其离子陷阱效应，并模拟了使用第二栅极后正离子回轰阴极的全过程和阴极受损情况。模拟结果证明，加入离子陷阱结构后可以明显改善场致发射三极管的离子轰击问题。     

自对准栅场发射三级管的设计

对于场发射三极管，提高使用频率，增加跨导以提高增益是设计的关键。因此，本文在研究场发射三级管工作原理的基础上，重点分析了场发射三极管结构参数与电参数的关系。     

真空微电子三极管几何参数的设计考虑

真空微电子三极管是近年来兴起与发展的真空微电子学中的一类重要器件。本文从真空微三极管的工作特性出发,分析了这类器件中所需考虑的几何参数和工作特性的关系,并给出了一些理论和实验公式,为今后的设计提供一些参考。     

电子跳跃结构场发射阴极的电子通过率研究

针对一种基于二次电子发射的跳跃电子阴极三极管结构进行了研究,这种特殊结构可以有效地提高了电子注电流密度。并减小受残余气体离子的对阴极轰击造成的阴极发射跌落。对应用碳纳米管场发射的跳跃电子阴极的三极管结构的电子通过率的研究,提出了的栅网上蒸镀高二次电子发射系数的介质膜的方法,可以有效地解决栅网的截获问题,提高电子通过率。     

场发射金属尖阴极阵列的制备

本文采用ＳｉＯ２作锥尖的塑模，再利用塑模制备出场发射金属尖阴极阵列，并给出ＳＥＭ金属尖照片，分析了工艺因素对金属尖的影响，同时提出了真空微电子二极管和三极管的设想。     

平面型纳米真空三极管的计算机模拟

平面纳米真空三极管只需要平面工艺,与现有的微电子工艺兼容,与基于经典Spindt阴极的真空微电子三极管相比,具有工艺相对简单等特点,同样具备纳米真空电子器件抗辐射、温度稳定性好等优点。本文采用粒子模拟方法对平面型纳米真空三极管的场发射特性进行了计算机模拟研究,模拟中考虑了空间电荷的影响。典型器件的模拟结果表明,平面型纳米真空三极管具有信号响应速度快,工作电压较低等优点。研究了该三极管结构中的尖端曲率半径、尖端相对高度、栅极电压和阳极电压对场发射特性的影响,有助于设计和优化该类器件结构。这种平面型纳米真空三极管可望成为真空集成电路的基础器件,并在卫星等航空航天领域等需要抗辐射领域获得应用。     

横向场发射三极管

利用薄膜边缘场发射阴极设计的三极管、阴极、栅极和阳极是平面结构，因此极间电容小，适合应用于高速和高频电路。它在工艺上与半导体器件兼容，工艺比较简单，是真空微电子集成电路中的有源器件，它有着广泛的应用前景。     

硅薄膜场发射阴极的制造和性能

本文评述了薄膜场发射阴极的一般制造方法后,介绍了我们的制造技术。我们用硅材料为基体,用各向同性的湿法化学腐蚀工艺制出尖端,用氧化增尖和自对准栅极工艺制成TFFEC—薄膜场发射阴极。外加阳极就构成了三极管。本文给出了TFFEC和三极管的测试性能。     

具有汇聚特性的场发射电子源的模拟研究

提出了一种具有汇聚特性的新型场发射阴极结构,利用有限元方法模拟计算了此种阴极结构在不同参数条件下的电场分布、电子轨迹,考察了不同参数对电子汇聚效果的影响,给出了此种场发射阴极的栅极-阴极间距、栅极宽度、阳极电压、栅极电压等基本参数对汇聚效果的影响.模拟计算结果表明,电子束的汇聚程度随着栅极-阴极间距的增大而增大,随着栅极宽度的增大而减小;电子束的汇聚程度与阳极电压、栅极电压参数密切相关,并存在最优参数.     

电泳法制备平栅极碳纳米管场发射阴极及场发射特性研究

采用电泳法在ITO玻璃基板上选择性制备了碳纳米管(CNTs)阴极薄膜,采用电子扫描(SEM)分析了CNTs薄膜的表面形貌,并测试了碳纳米管阴极的场致发射特性.结果表明,利用电泳法制得的碳纳米管阴极薄膜均匀性、致密性良好,且具有较大发射电流密度;通过控制共面栅控CNTs场发射阴极的栅极电位能够有效控制阴极的场发射电流密度...     

碳纳米管冷阴极Pierce电子枪

为发展场致发射冷阴极毫米波电真空辐射源器件, 对利用大面积碳纳米管冷阴极产生大电流、高电流密度电子注的电子光学系统进行了研究.通过在Pierce电子枪阴极表面引入栅网结构, 解决了碳纳米管冷阴极场致发射所需的强电场和电子聚束问题.在碳纳米管冷阴极实验测试数据的基础上, 采用粒子模拟软件对上述电子光学系统进行了仿真.研究了栅网对注电流、注腰半径和电子注散射的影响, 分析了阳极电压和外加轴向磁场对电子注的聚束作用.优化后的仿真结果表明在阴极发射面为3.03 cm2时, 该电子光学系统能够产生210 mA、60 kV, 电流密度为6.7 A/cm2, 最大注半径为1mm的电子注.     

多级场发射结构模拟及特性研究

以场发射基本原理为基础,建立四种四极管模型,采用有限差分法对微孔径场发射阵列进行了模拟.在建立模型时,采用的是相同的结构参数,如栅极到阳极间的距离,发射体尖锥的材料和形状,绝缘层的厚度以及各个结构体的电压.各个模型不同的地方在于聚焦级的位置和厚度不同.通过调整聚焦级的位置找到各种结构的最佳发射性能位置,然后通过比较在不同栅极电压的情况下,比较四种结构发射的特性如聚焦性和电流大小,得到一般性结论,并讨论分析了导致电子束光斑大小变化的原因,得出与实际相符合的数值模拟和优化结构,为试验提供设计依据.     

纳米多孔硅的场致电子发射性能研究

对采用阳极氧化法及阴极还原表面处理技术制备的性能稳定的纳米多孔硅,用原子力显微镜(AFM)表征了其微观结构,多孔硅颗粒粒径在30 nm左右.室温条件下测试了多孔硅场电子发射的特性,结果表明,多孔硅具有很好的场致发光性能,在5 V/μm的电场下就可以产生场发射电流.多孔硅的开启电压在1 000 V左右,发射电流随着电压的增大而不断增大,发射电压在2 000 V以上.

Abstract：

Nanoscale porous silicon (PS) was prepared by anodic oxidation, cathode reduction and surface treatment technique. The porous silicon particles with the average diameter of about 30 nm were obtained by characterizing their microstructure with atomic force microscope (AFM). Electron field emission characteristics of porous silicon were investigated at room temperature. The resuhs demonstrate that porous silicon has favorable electroluminescence properties, and the field emission current can be generated only under the electric field of 5 V/ μm. And the turn - on voltage is about 1 000 V. With the increase of the offered voltage, the emission current is enhanced and the emission voltage is over 2 000 V.     

Analysis of Failure in Miniature X‐ray Tubes with Gated Carbon Nanotube Field Emitters

We correlate the failure in miniature X‐ray tubes with the field emission gate leakage current of gated carbon nanotube emitters. The miniature X‐ray tube, even with a small gate leakage current, exhibits an induced voltage on the gate electrode by the anode bias voltage, resulting in a very unstable operation and finally a failure. The induced gate voltage is apparently caused by charging at the insulating spacer of the miniature X‐ray tube through the gate leakage current of the field emission. The gate leakage current could be a criterion for the successful fabrication of miniature X‐ray tubes.     

Low-loss high-speed switching devices, 2300-V 150-A static induction thyristor

Focussing attention to the performance of high-speed high off-state voltage and large current provided in the buried-gate-type static induction (SI) thyristor, a 2300-V 150-A low-voltage-drop high-speed medium-power SI thyristor was developed. Irrespective of the magnitude of switching current, the SI thyristor has the characteristics of fast turn-on time and less on-gate current compared to that of the GTO thyristor. The characteristics of this SI thyristor obtained as the result of manufacturing this prototype were such that the forward blocking voltage was 2300 V at a gate reverse voltage of -5 V, the reverse blocking voltage was 2350 V, and the forward voltage drop was 1.4 V at an anode current of 150 A and 2.2 V at an anode current of 450 A. The switching characteristics were such that the turn-on time was 1.5 µs when an anode current IAof 150 A becomes ON, turnoff time was 2.5 µs at IA= 100 A and 3.6 µs at IA= 200 A. This SI thyristor is able to break the anode current of 1000 A at a gate current of 95 A. Performance exceeding 1100 A/µs was confirmed for the di/dt capability and even for dv/dt, and these normally can be operatable even at 100 times higher current compared with maximum average current.     

A novel approach for focusing electron beams using low-cost ceramicgrid [field emitter arrays]

A low-cost ceramic grid was used as a stand-alone focusing electrode in field emitter arrays to obtain high brightness and small electron beam size. The ceramic grid with an array of 200-μm holes was made from DuPont 591 with low-cost equipment. Beam size is controllable by the voltage applied to the focusing grid. Light intensity profiles were measured and analyzed. The full width at half maximum (FWHM) of the light profile excited by electron emission from 30-μm wide field emitter arrays is 60 μm at 5000 V with 6 mm anode-cathode separation. At an anode voltage of 2000 V and gate voltage of 55 V, focusing is optimized at a focusing voltage of 30 V. Arc-free operation at 10 kV was achieved, thereby promoting improved phosphor efficiency. This focusing approach may lead to improve lifetimes for field emission displays and other vacuum microelectronic devices by significantly increasing the total vacuum volume and providing a means for improved getter utilization     

全丝印后栅CNT-FED仿真及器件研究

模拟并制作了一种基于丝网印刷技术的后栅结构碳纳米管场发射显示器。采用有限元分析软件ANSYS对器件进行了电场模拟,优化了阴极宽度、阴极厚度、阴极间隙、介质层厚度等结构参数。取最优参数制作了像素为30×30,发光面积为54mm×54mm的单色显示屏。在阳压为1500V、栅压为300V时,器件发射电流密度达到5μA/cm2。该器件制作成本低,稳定性和均匀性良好,可矩阵寻址实现字符显示。     

Ultralow-voltage boron-doped diamond field emitter vacuum diode

A boron-doped diamond field emitter diode with ultralow turn-on voltage and high emission current is reported. The diamond field emitter diode structure with a built-in cap was fabricated using molds and electrostatic bonding techniques. The emission current versus anode voltage of the capped diamond emitter diode with boron doping, sp² content, and vacuum thermal electric (VTE) treatment shows a very low turn-on voltage of 2 V. A high emission current of 1 μA at an anode voltage of less than 10 V can be obtained from a single diamond tip. The turn-on voltage is significantly lower than comparable silicon field emitters