基于X光移动光刻技术的PMMA微透镜阵列制备

Fabrication of PMMA micro lens array based on X-ray moving lithography

微透镜阵列的制备已经成为微光学领域的研究热点。利用两次X光移动光刻技术,以聚甲基丙烯酸甲酯(PMMA)为正光刻胶,在PMMA基板上制造了微透镜阵列,并对其制作原理进行了详细说明。设计了制备微透镜阵列用的掩膜图形,并通过掩膜图形模拟仿真,预测了微透镜在两次移动曝光显影后的形状。第一次X光移动光刻后,理论上会得到半圆柱状三维结构;第一次光刻后将掩膜板旋转90°,进行第二次移动曝光光刻,最终在PMMA基板上制备了面积为10 mm×10 mm的30×30个微透镜阵列,阵列中每个微透镜的直径约248μm、厚度约82μm。同时也研究了X光曝光量与PMMA刻蚀深度之间的关系。微透镜阵列形貌测试表明此种制备微透镜阵列的新方法是可行的。

Fabrication of micro lens arrays has been a research hotspot in the area of micro optics. By using two X-ray moving lithography, the polymethyl methacrylate （PMMA） as the positive photoresist, the micro lens array was manufactured on PMMA plate, and its fabrication principle was described in detail. The related mask pattern for fabricating micro lens arrays was designed. Through designed mask patterns simulation, the shape of the actual micro lens could be predicted. After the first moving x-ray lithography, theoretically the semi-circular columnar micro 3D structure was formed on the PMMA substrate. If the mask mounted vertically was rotated 90° after the first X-ray lithography and the second X-ray lithography was carded out, eventually the 30x30micro lens array was obtained on the 10mm×10mm PMMA substrate, the diameter of each micro lens was about 248μm, the depth was about 82μm. The relationships between the amount of X light exposure and the depth of PMMA etching was studied. The micro lens array profile measurement shows that the new method for the fabrication of micro lens array is proved to be feasible.