面向大尺寸、高密度光栅的并行激光直写新技术研究

项目名称： 面向大尺寸、高密度光栅的并行激光直写新技术研究

项目编号： No.61307064

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 无线电电子学、电信技术

项目作者： 麻健勇

作者单位： 中国科学院上海光学精密机械研究所

项目金额： 28万元

中文摘要： 针对国家激光点火工程中对核心器件-脉冲压缩光栅密度进一步提高的迫切需求，基于径向偏振光和二元相位板，提出了一种并行激光直写光栅的新技术，设计合适的二元相位板，在高数值孔径的情况下，不仅可以实现超越衍射极限的光斑，满足脉冲压缩光栅密度不断增大的要求，同时大大延长了系统的焦深，降低了对伺服聚焦系统响应速度的要求，克服了在高速刻写过程中，曝光条纹不均匀的问题，使并行激光直写的速率有了数量级的提升。利用径向光聚焦在焦点形成的强纵向电场可以提高条纹对比度，提高光栅掩膜的质量，同时聚焦激光束纵向能量密度均匀分布，可以大大改善移动平台pitch抖动带来的不利影响，提高光栅的直写成品率。实验表明，相比于传统的并行激光直写光栅技术，本申请提出的新技术，在相同刻写速率的情况下，刻写光斑的质量有了明显的改善，制备出的光栅掩膜周期500nm，线宽小于250nm，完全满足实际的工程需要。

中文关键词： 达曼光栅；激光直写；伺服聚焦；；

英文摘要： With the urgent demand to further improve the density of pulse compression grating(PCG), a key optical element in the laser ignition project,we propose a new technology for parallel laser direct writing system. Based on radial polarized light and binary phase plate, we can not only obtain the spot beyond the diffraction limit，which meet the requirement of increasing the pulse compression grating density, but also greatly extend the depth of focus，which can improve response of servo focusing system, therefore,the speed of laser writing system have one order of magnitude improvement with better uniform of grating mask.In additon,the quality of grating mask can be greatly improved with the stronge longitudinal electric field formed around the focal plane,beside,the uniformal distribution of energy density can reduce the influence of pithch vibration of mobile stage and hence improve the yield of productions of grating mask. It is demonstrated from our experiments that the spot quality has been greatly improved in the same writing speed compared with the traditional parallel laser direct writing technology.In addtion, based on this new technology,the grating mask with grating period of 500nm and line width less than 250 nm have been fabricated,which can fully the actual requirement of our project.

英文关键词： Dammann grating；Direct Laser Writing；Auto-focusing Servo symstem；；