针对工件台制造和装配过程中产生的移动直线性误差,建立了掩模沿曲线移动时曝光量与曲线和移动距离之间关系的数学模型。通过对实测工件台移动直线性误差规律的分析,确定了近似的移动曲线函数。利用MATLAB进行数值模拟的方法,分别模拟了沿理想直线移动、不同幅值和不同移动距离的曲线移动时,所获得元件的面形,并分析了面形误差的影响因素和“竹节”误差产生的原因。最后得出结论:通过控制移动距离为一倍的掩模图形重复周期,并减小工件台移动直线性误差,对控制元件的面形精度和“竹节”误差最为有利。
In view of the moving linear error caused by the manufacturing and assembling of stage in the mask moving exposure technique, a mathematical model of relationships among exposure flux, moving curve and moving distance was built when mask moved along the curve, According to the real test result of linear error of stage, approximate function of stage moving curve was obtained. By use of numeric simulation with Matlab, the simulation of surface topography of exposed elements was carried out based on the following situation: mask moving along ideal beeline, along curve of different amplitude and different moving distance. The factors of surface shape accuracy and 'bamboo' shape variation error were analyzed. Results show that the surface shape errors of element can be controlled by reducing the stage moving linear error and adjusting mask moving distance that is equal to one repeated period of mask geometric figures