激光光刻大面积扫描投影成像光学系统测试及评价

基于351nm XeF激光大面积投影成像光刻系统,通过对其光学系统包括光学照明系统和折叠投影系统进行光学性能测试。由激光经过柱面透镜、微透镜阵列均束器以及投影折叠物镜之后产生的能量及光束质量变化,将准分子激光光束均匀性评价指标部分运用到光学系统的评价之中,得到光学系统在不同关键位置的能量分布曲线以及平顶因子关系图,表明微透镜阵列均束器虽保证了整个光学系统各处光斑的均匀性,但衍射却造成了能量利用率的降低。同时,通过对印制电路板(PCB)和玻璃(ITO)进行曝光和显影实验,表明该双远心共焦投影光学系统,只要控制使均匀输出的能量符合曝光剂量,就能够满足分辨率的要求。

Measurement and Evaluation for the Optical System in Laser Large-Area Scanning Projection Imaging Lithography

Based on the system of a large-area laser projection imaging lithography using 351 nm XeF excimer laser,some optical properties of the system including illumination system and folded projection system are measured.According to the variation of energy and beam quality of the beam passing through two cylindrical square lenses and two microlens arrays and projection folded system,some evaluating norm about excimer laser beam uniformity is partly adopted to evaluate this optical system.The energy distribution on different crucial areas of the optical system and the top-hat factor can be obtained.The results show that the microlens array maintains the beam uniformity,whereas the energy utilization rate is suppressed due to the diffraction.Meanwhile,through the printed circuit board(PCB) and ITO lithographic experiment,it shows that the designed double-telecentric confocal projection lithographic system can meet the required resolution,provided the uniform-output energy is controlled to be in accord with the exposure dose.