摘要
针对电子束领域中透镜对中效率低、精度差和多变量耦合复杂的问题,提出了一种基于传输矩阵与分步梯度合并的全自动对中方法。首先构建了上下对中线圈与电磁透镜的级联传输矩阵模型,量化描述线圈电流与透镜激励对束斑位置和光轴偏差的耦合关系。基于该模型,设计了同时约束位置误差和对中稳定性的损失函数,以平衡快速收敛与焦距变化下的稳定性。其后,采用两阶段梯度合并算法,即先计算位置误差梯度,再计算对中条件梯度,并以自适应步长更新线圈电流,实现高效迭代校正。实验结果表明,该方法在有限扫描次数内即可将束斑偏差收敛至纳米级别,显著提升了透镜对中的速度与精度。
An automatic lens alignment method for variable shaped electron beam lithography systems is presented.A cascaded transmission-matrix model of centering coils and electromagnetic lens is developed to quantify the coupled effects of coil currents and lens excitation on beam spot displacement and optical axis deviation.A dual-constraint loss function is formulated to balance rapid convergence and stability under focal changes.A two-stage gradient fusion algorithm,first computing position-error gradients,then centering-condition gradients with adaptive step-size updates enables efficient current calibration.Experimental validation demonstrates micrometer-level alignment within minimal scanning,substantially improving alignment speed and accuracy.
作者
苏鑫
黄少冰
章卓
李杰
梁文彬
谭小林
SU Xin;HUANG Shaobing;ZHANG Zhuo;LI Jie;LIANG Wenbing;TAN Xiaolin(The 48^(th)Research Institute of CETC,Changsha 410004,China)
出处
《电子工业专用设备》
2025年第5期13-17,52,共6页
Equipment for Electronic Products Manufacturing
关键词
电子束领域
透镜对中
传输矩阵
分步梯度合并
自动校正
Electron beam field
Lens alignment
Transmission matrix
Two-stage gradient fusion
Automatic calibration
