电子束静电折板偏转系统研究

以SDS-3电子束曝光机为基础,用折板结构静电偏转替代直板结构静电偏转,探讨了电子束曝光机折板静电偏转场的电子轨迹与电位分布应满足的要求。导出了折板静电偏转灵敏度与电位分布之间的关系,给出静电偏转像差方程及像差系数。用矢量描写电子轨迹,以积分式表示像差系数,给出了折板结构方程与参量。像差系数适应计算机辅助运算。结果表明,折板结构静电偏完成的图像像差明显优于原直板结构静电偏。提供了静电折板偏转与直板偏转的相关计算数据及摩尔栅条纹图。     

电子束曝光机静电偏转系统

以静电极板为电子束曝光机偏转负载，用双通道扫描原理进行扫描，并使用计算机辅助设计研究电子束曝光机聚焦偏转系统的结构。由SDS-3电子束曝光机试验结果表明，复合静电偏转可以达到磁偏转相似的像差水平。     

用于电子束曝光机中的“摆动物镜”(SOL)

本文讨论了复合磁透镜和磁偏转器场中,电子束主轨迹和偏转像差之间的关系。为了改善电子束扫描系统的性能,本文提出了一阶近似的电磁摆动物镜(Swinging Objective Lens)(SOL),给出了摆动物镜的像差系数。本文讨论了建立在摆动物镜基础上的适用于电子束曝光机的实际扫描系统。为了减小系统的总像差,结合电子光学的条件,采用了“权复形”最优化方法,得到了实际的复合结构;在0.005弧度半张角、高压波动0.0001、象距50mm的条件下,在5×5mm~2扫描场的边角处,动态校正前的总像差斑为0.083 μm。     

电磁复合场三级几何像差方程的修正与像差系数

本文基于作者提出的“函数逼近的数值迭代概念”，修正了电磁复合场中电子成像系统的三级几何像差方程式，给出了具有更高精度的像差计算公式和用集中参数形式描述的像差系数表达式，为像差的数值计算和电子光学系统的计算机优化设计提供了实用的理论依据。     

磁极自会聚偏转系统设计研究

本文对具有较高偏转灵敏度的多段式磁极自会聚偏转系统的结构形式、设计原理、偏转像差的校正方法进行了介绍，并对５１ＦＳ，９０°偏转角的两段式磁极偏转系统计算机辅助设计结果进行了讨论。     

DY-2001A型纳米级电子束曝光机中静电偏转器的设计

基于纳米曝光要求和JSM-35CF型扫描电镜,设计了一组上下偏转器长度不一致的静电偏转器,使偏转灵敏度大大提高.采用二阶有限元法计算了八极静电偏转器的轴上场分布.高精度的场分布有利于高级像差.为了使系统的总体像差最小,结合具体电子光学系统,用最小二乘法对偏转器的激励强度、转角及其在系统中的位置进行优化,得到直至五级分量的像差.动态校正后,偏转场为80μm×80μm时,束斑分辨率约为3.2 am;偏转场大小为1 mm×1 mm时,束斑分辨率约为29.8 nm.结果表明,应用该组静电偏转器的电子光学系统的分辨率满足纳米曝光的要求.     

偏转像差中的Dilemma效应

本文应用多级场像差校正理论，通过对大偏转角下五级偏转像差中的彗差进行分析得出，在五级偏转彗差中存在Ｄｉｌｅｍｍａ效应，即五级彗差的某种线性组合是一常数，它不受十极场的影响。五级彗差应在这个常数为０或较小值时，通过调整十极场分布进行校正，对影响Ｄｉｅｍｍａ常数的因素进行了计算分析。     

一种极低场曲复合聚焦偏转系统的设计

本文提出了一种用系统本身预偏转和主偏转象差相抵消来消除电子光学场曲的方法。采用解析函数近似表示系统场分布和电子轨迹,对象差进行了理论分析和解析计算,表明在一定条件下,可以完全消除复合聚焦偏转系统的彗差和横向色差,并使场曲达到极小。由设计实例可见,该系统在10×10mm~2扫描范围内,场曲仅为0.013μm。     

多极场对Trilemma效应影响的研究

Ｔｒｉｌｅｍｍａ效应是偏转系统实现自会聚的一个重要判据，对高级偏转像差的校正，需要考虑高阶Ｔｒｉｌｅｍｍａ效应的影响，本文给出了对直至七阶的Ｔｒｉｌｅｍｍａ常数调整时，２ｎ多极场对ｎ阶Ｔｒｉｌｅｍｍａ常数影响的表达式，并对此影响进行了计算。     

多极场对Trilemma效应影响的研究

Ｔｒｉｌｅｍｍａ效应是偏转系统实现自会聚的一个重要判据，对高级偏转像差的校正，需要考虑高阶Ｔｒｉｌｅｍｍａ效应的影响，本文给出了对直至七阶的Ｔｒｉｌｅｍｍａ常数调整时，２ｎ多极场对ｎ阶Ｔｒｉｌｅｍｍａ常数影响的表达式，并对此影响进行了计算。     

七级偏转象差中的Trilemma效应

Trilemma效应是偏转系统实现自会聚的一个重要判据,对高级偏转象差的校正,需要考虑高阶Trilemma效应的影响,本文从多极场偏转象差校正理论出发,应用区域分割的方法,对直至七阶的Trilemma效应进行了分析,给出了各阶Trilemma常数的表达式,其中七阶Trilemma常数可以作为大偏转角偏转象差校正的判据。     

Electron optical aberration calculations in a homogeneous magneticdeflection system with curved axis at extra-large defection angles

In the authors' previous paper, variational deflection aberration theory has been developed for nonhomogeneous magnetic deflection systems with curved axes at extra-large deflection angles. Based on the variational deflection aberration theory, a magnetic deflection system consisting of a homogeneous deflection field and a homogeneous sextupole field has been further investigated in the present paper. For such a magnetic deflection system, both the Gaussian trajectory and all second- and third-order aberrations have been calculated analytically and been expressed by algebraic-trigonometric formulae suitable for computer computations. It is to be expected that the present research and computational results may be useful in designing high-performance magnetic deflection systems for high-definition television color picture tubes with self-convergence     

Computer calculation of deflection aberrations in electron beams

The aberrations of a magnetically deflected electron beam are investigated in detail using an IBM 7094 computer. The computer programming is applicable to the case of one-dimensional deflection through small angles. The beam is treated as a group of electrons having no internal interactions, no energy spread, and producing no external fields. The field distributions that would produce minimum total aberration for a range of specified working distances, maximum deflection distances, coil widths, and coil openings are calculated. The aberrations produced by these ideal fields and by fields that deviate from the model are predicted. Typically, for a working distance of 3 in (7.62 cm), field coverage of 11 mm, and beam convergence angle of 3.54 × 10^-3rad, the maximum increase in spot diameter is of the order of 0.05 micron. Theoretical limitations on the minimum aberration of a specific deflection system are established. The aberration is expected to be further minimized if dynamic astigmatic correction, as described in this paper, is applied.     

A unified aberration theory for magnetic deflection systems withrectilinear or curvilinear axes

A unified deflection aberration theory has been further developed for magnetic deflection systems with curvilinear or rectilinear axes. By using variational method, primary-order deflection aberrations with respect to curvilinear or rectilinear axis can be universally calculated by means of gradient operations on eikonal (the function of optical length). Conventional pure-order rectilinear-axis theory can be derived from a curvilinear axis eikonal of mixed-order in the rectilinear limit. By introducing general aberration integration functions in terms of mathematical operators, all primary-order deflection aberrations have been explicitly expressed in compact formulae suitable for computer computations. It is to be expected that the unified deflection aberration theory may be useful in designing high-quality magnetic deflection systems for high-definition television color picture tubes     

Variational aberration theory for magnetic deflection systems with curved axes at extra-large angles

Variational deflection aberration theory has been further developed for deflection systems with curved axes at extra-large deflection angles (up to 120/spl deg/). The variational method allows us to calculate second- and third-order deflection aberrations with respect to a curved axis by means of gradient operations on eikonal (the function of optical length). All second- and third-order deflection aberrations have been explicitly expressed in compact and appropriate formulae suitable for computer computations. It is to be expected that the variational deflection aberration theory may be useful in designing high-quality magnetic deflection systems for high-deflection television color picture tubes.<>     

平行板偏转系统的几何象差和优化设计

本文从理想均匀静电场偏转系统三级几何象差的公式出发,导出了由两对互相垂直的偏转板组成的平行平板偏转系统的三级几何象差公式。这些公式不但可用来快速估算偏转象差,还可用来作为校验数字计算程序的理论模型。从水平和垂直方向偏转象散和场曲的影响应相同这一要求出发,提出了一种优化设计方法。在给定偏转区总长度和两对偏转板之间的距离后,可以计算出每对偏转板的最佳长度。文中给出了设计数表,并比较了平行平板偏转系统和八极偏转系统的优缺点。     

Feasibility of multi-beam electron lithography

The achievable throughput of a high-resolution electron-beam pattern generator in which a matrix of 1000 individually blankable 0.1-μm-sized pixels is scanned in a raster should be about 0.5 cm²/s. This is an order of magnitude greater than for the best existing shaped-beam vector-scan machine. The matrix could be formed by splitting a solid beam into beamlets which pass through an array of blankers. The beam splitter and array optics can be corrected for spherical aberration so that all the beamlets can be brought together at the entrance to the projection/deflection system.     

Dilemma效应与Trilemma效应

在大偏转角自会聚彩色显像管的五级偏转像差中存在彗差校正的Ｄｉｌｅｍｍａ效应和像散校正的Ｔｒｉｌｅｍｍａ效应，即五级彗差的某种线性组合过及五级像散的某种线性组合均是常数，它们不受１０极场的影响。对于大偏转角五级彗差和像散的校正，应在Ｄｉｌｅｍｍａｔ Ｔｒｉｌｅｍｍａ常数均为０或较小值时，通过调整１０极场分布进行校正。