强流微束斑电子束系统的研究和设计计算.pdf

强流微束斑电子束系统的研究和设计计算 郭小立* 唐天同 康永锋 任岩 （西安交通大学电子与信息工程学院西安 710049 ） Study on intensity current electron beam systems with micro-spot sizes Guo Xiaoli, Tang Tiantong, Kang Yongfeng, and Ren Yan (School of Electronic and Information Engineering, Xi’an Jiaotong University, Xi’an, 710049, China) Abstract The forming of electron beams with intensity current and micro-spot sizes is studied. A new combined electrostatic-magnetic electron lens is put forward; its maximum axial magnetic field is located near the crossover of the electron beam, with a retarding electric field caused by the electrodes, and the blur of the spot caused by the space-charge repulsion is reduced effectively. A modified Vlasov equation, which describes the evolution of current density distribution, is used to study the electron beam systems with high current; the excitation of lens and the initial conditions of injected beam are investigated numerically to explore their effects on the current density evolution of the electron beams. It was found that it is able to generate intensity current electron beams with micron spot sizes if side pole gape lens and relevant electrodes is used. An electron beam system with beam current 1.96mA and spot radius 4.2 μm is designed. Keywords: Intensity current electron beams, Micro-spot sizes, Evolution of current density distribution, Side pole-gap electron lens, combined electric-magnetic focusing. 基金项目：教育部博士点基金资助项目（No.20020698020 ） *联系人：硕士生，E-mail ：xlguo@ ，Tel ：029-826686