为了研究基片的直边衍射效应对激光汇聚铬原子沉积特性的影响, 利用半经典模型, 采用改进后的设定恰当步长的4阶龙格-库塔算法, 模拟了铬原子在直边衍射激光驻波场中的3维运动轨迹和3维沉积光栅结构, 研究了衍射边与反射镜的距离、激光中轴线与基片表面的距离对激光汇聚原子沉积过程的影响。结果表明, 基片摆放位置不同, 沉积效果受到衍射效应的影响程度也随之改变;当衍射边到反射镜的距离为0.81cm、激光中轴线与基片表面的距离为0.01mm时, 纳米光栅的半峰全宽最小, 同时对比度最大。该研究成果为原子光刻实验提供了丰富的理论指导。

In order to study the influence of straight edge diffraction on the deposition characteristics in the process of laser-focused Cr atoms, the improved fourth-order Runge-Kutta algorithm was adopted to simulate the 3-D trajectory and deposition grating of Cr atoms in the straight edge diffraction laser standing wave field based on the semi-classical model. The influence of the distance from diffraction edge to mirror and from laser medial axis to substrate surface on laser focused atomic deposition process were described. The results show that diffraction effect on the deposition effect will be changed by the different substrate placement. When the distance from diffraction edge to mirror equals 0.81cm and the distance from laser medial axis to substrate surface equals 0.01mm, the full width at half maximum of nanograting reaches the minimum, at the same time, the contrast reaches the maximum. The research results provide a richer theoretical guidance for atomic lithography experiments.