场致发射电流对高气压间隙击穿场强的影响  

Effect of Field-Emission Current on Breakdown Field Strength of High-Pressure Gas Gap

作　　者：张喜波[1,2] 苏建仓[1,2] 孙旭[1,2] 赵亮[1,2] 李锐[1,2] 

机构地区：[1]西北核技术研究所,西安710024 [2]高功率微波技术重点实验室,西安710024

出　　处：《现代应用物理》2015年第1期42-45,共4页Modern Applied Physics

摘　　要：气压较高时,电极间隙击穿场强偏离巴申曲线。分析认为,间隙击穿前,金属微凸场致发射电流持续加热电流通道内的气体,导致气体温度上升和通道内气体分子数密度降低,由于电子平均自由程与气体分子数密度成反比,因此随着平均自由程的增大,电子更容易获得足以导致"雪崩"的能量,进而降低了对间隙电场强度的要求,即场致发射电流的加热效应在某种程度上抵消了增大气压对击穿场强的提升效果。推导给出了修正的气体间隙击穿场强表达式,场增强因子处于合理范围内,结论可解释实验现象。Under high pressure,the breakdown field strength in electrode gap will depart from the Paschen curve,and the field emission preceding electrical breakdown caused by the micro-protrusions on the cathode surface will heat the gas in the current channel,leading to decrease of the gas density in the channel,and thus reducing the sensitivity of the breakdown field strength to the pressure.In this paper,a modified expression for breakdown field strength is presented which can well express the phenomena in field emission,with a field enhancement factor in a reasonable range.

关 键 词：场致发射 击穿场强 巴申定律 气体开关 

分 类 号：TN78[电子电信—电路与系统]