本文選題：場致發(fā)射陰極　切入點(diǎn)：碳納米管　出處：《電子科技大學(xué)》2015年碩士論文　論文類型：學(xué)位論文

【摘要】：碳納米管(CNT)具有優(yōu)良的場致發(fā)射特性,是冷陰極器件的理想陰極材料。為發(fā)展碳納米管冷陰極微波、毫米波電真空輻射源器件,本文對碳納米管冷陰極的場發(fā)射特性進(jìn)行了研究,設(shè)計(jì)了一只可工作于8mm波段的碳納米管冷陰極返波振蕩器。主要工作內(nèi)容如下:(1)對直徑為4mm的圓形平面陰極進(jìn)行了實(shí)驗(yàn)測試,獲得其最大發(fā)射電流密度為127mA/cm2。在實(shí)驗(yàn)的基礎(chǔ)上,結(jié)合粒子模擬軟件CST建立了大面積碳納米管冷陰極的場發(fā)射模型。研究了柵網(wǎng)結(jié)構(gòu)對碳納米管冷陰極場發(fā)射性能的影響,獲得了矩形柵網(wǎng)結(jié)構(gòu)的優(yōu)化尺寸,當(dāng)d=0.1mm,D=4d時(shí),陰極的發(fā)射性能較好,電子注通過率約為60%。(2)設(shè)計(jì)了柵控結(jié)構(gòu)的碳納米管冷陰極帶狀注電子槍。分析了柵網(wǎng)結(jié)構(gòu)、陽極電壓、聚焦磁場等參數(shù)對帶狀注電子槍性能的影響。優(yōu)化結(jié)果表明該電子槍在陰柵間距0.25mm,柵網(wǎng)電壓2.5kV時(shí),能產(chǎn)生工作電壓在18kV,電流為1.5A,注半徑為0.35mm,電流密度高達(dá)17.2A/cm2的帶狀電子注。(3)結(jié)合本征求解法對金屬矩形雙柵慢波結(jié)構(gòu)的色散特性進(jìn)行了推導(dǎo)和研究,利用三維粒子模擬軟件CST設(shè)計(jì)了可工作于8mm波段的金屬矩形雙柵慢波結(jié)構(gòu)。(4)將碳納米管冷陰極用作返波管的粒子發(fā)射源,通過軟件Magic和CST仿真設(shè)計(jì)了可工作于8mm波段的碳納米管冷陰極返波管。仿真結(jié)果表明,該碳納米管冷陰極返波管能產(chǎn)生工作頻率為33.95GHz,輸出功率為2.35kW,效率達(dá)8.73%的返波信號。
[Abstract]:Carbon nanotube (CNT) has excellent field emission characteristics and is an ideal cathode material for cold cathode devices. In this paper, the field emission characteristics of carbon nanotube (CNT) cold cathode are studied, and an 8 mm band CNT cold cathode backwave oscillator is designed. The main work is as follows: 1) the circular planar cathode with a diameter of 4 mm is experimentally tested. The maximum emission current density is 127 Ma / cm 2. On the basis of experiments, a field emission model of large area carbon nanotube cold cathode is established based on particle simulation software CST. The effect of grid structure on field emission performance of carbon nanotube cold cathode is studied. The optimum size of rectangular grid structure is obtained. When the grid structure is 0.1 mm / d, the emission performance of the cathode is better, and the electron beam passing rate is about 60.0.The grid-controlled carbon nanotube cold cathode ribbon electron gun is designed, and the grid structure and anode voltage are analyzed. The influence of focusing magnetic field and other parameters on the performance of the belt electron gun is obtained. The optimized results show that the electron gun has a gap of 0.25 mm and a grid voltage of 2.5 kV. The dispersion characteristics of metal rectangular double-gate slow-wave structures are deduced and studied by using this solicitation method, which can generate a working voltage of 18 kV, a current of 1.5 A, a beam radius of 0.35 mm, and a current density of up to 17.2 A / cm ~ 2. Using 3D particle simulation software CST to design a metal rectangular double-gate slow-wave structure. 4) the carbon nanotube cold cathode is used as the particle emission source of the backwave tube. Through the software Magic and CST simulation, the CNT cold cathode backwave tube which can work in 8mm band is designed. The simulation results show that the CNT cold cathode backwave-return tube can produce a signal with working frequency of 33.95 GHz, output power of 2.35 kW and efficiency of 8.73%.
【學(xué)位授予單位】：電子科技大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2015
【分類號】：TN125

【參考文獻(xiàn)】

相關(guān)期刊論文 前1條

1 袁學(xué)松;張宇;孫利民;黎曉云;鄧少芝;許寧生;鄢揚(yáng);;碳納米管冷陰極脈沖發(fā)射特性及仿真模型研究[J];物理學(xué)報(bào);2012年21期

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本文編號：1594726