GEM电场和电子轨迹的三维模拟研究  

3D Simulation Study of Electric Field and Electron Trajectories in Gas Electron Multiplier

作　　者：秦娜娜[1] 屠彦[1] 杨兰兰[1] 

机构地区：[1]东南大学电子科学与技术学院显示技术研究中心,南京210096

出　　处：《电子器件》2012年第3期253-257,共5页Chinese Journal of Electron Devices

基　　金：国家自然科学基金项目(60871015;50907009);国家863计划项目(2008AA03A308)

摘　　要：利用有限元法模拟了三维双碗型GEM电场和电子轨迹,计算了不同几何尺寸(包括小孔外径D、内径d、厚度T)和电参数(GEM上下电极电压差Vgem、漂移电场场强Ed、收集电场场强Ei)下的静电场和电子轨迹,研究不同几何结构和电参数对电场分布和电子透过率的影响。分析表明,D、T、Vgem对场强分布的影响比较大,d、Ed、Ei对GEM微孔内的电场影响不大。只有D、d、Ed、Vgem会对电子透过率产生影响,其余参数改变下的电子透过率与文中基准模型的一样,为35.26%,结果表明几何光学的透过率和微孔附近的电场共同决定了GEM中的电子透过率。The distributions of 3D electric field and the electron trajectories of double bowl structure gas electron multiplier（GEM）are simulated based on the finite element method.The electric field and electron trajectories of GEM for different geometric sizes and electrical parameters have been investigated,including external and internal diameters（D and d）,Kapton foil thicknesses（T）,the GEM voltage（Vgem：the voltage difference between the two copper electrodes on both sides of the GEM Kapton foil）,the drift electric field（Ed）,and the induct electric field（Ei）.Moreover,electron transparencies for different parameters are calculated at the same time.It shows that,D,T and Vgem have great effects on the electric field inside the GEM hole while there is no influence of d,Ed and Ei on the electric field.Only the D,d,Ed and Vgem can influence the electron transparency,the electron transparencies of other parameters are 35.26%.In addition,the influences of（D/P）^2 and Eh（the estimated electric field inside the GEM hole）on the electron trajectories have been researched.And it indicates that the geometry transparency and the electric field around the GEM hole is decisive to the electron transparency.

关 键 词：气体电子倍增器 电场分布 有限元法 双碗型 电子轨迹 电子透过率 

分 类 号：TL811[核科学技术—核技术及应用]