设计了一套用于准分子激光低温多晶硅制备的线光束整形系统。系统中设置的光斑转换模块可使原始光束截面横纵倒置; 利用扩束模块对原始光束的短轴进行准直, 其扩束倍率可限定短轴光束尺寸, 以配合短轴光束均匀模块的孔径; 采用基于透镜阵列的长轴、短轴光束均匀模块可在提高光斑能量分布均匀性的同时, 约束光斑尺寸; 系统中设置了投影模块, 可将光束投影于工件表面。为了实现系统中光学原件的精密定位, 设计并加工了配套的机械调节结构; 结合仿真实验, 讨论了阵列单元的中心偏差及工作面的偏离对线光斑质量的影响。利用该线光束整形系统对自行研制的大能量准分子激光光源进行整形, 实测的系统能量传递效率为33%, 工件表面的光斑尺寸约为100 mm×0.3 mm, 平均能量密度为470 mJ·cm-2, 长轴能量分布均匀度为93.95%, 满足退火技术的要求。

A line beam shaping system is developed for low temperature poly-silicon preparation with excimer laser. A spot conversion module is installed to make the beam cross sections of horizontal axis and vertical axis exchange their position. A beam expanding module is used for collimating the short axis of the initial beam, and its magnification determines the spot size of the short axis to match the aperture of the short axis beam homogenizer. The beam homogenizers for long and short axes based on lens array are used to improve the homogeneity of the spot energy distribution and restrict the spot size. A projector is installed to project the beam to the work piece. In order to realize precision positioning of the optical elements, a mechanical adjusting structure is designed and manufactured. The effects of the center error of the lens array unit and the deviation of the working plane on the line beam quality are discussed based on the simulation. The line beam shaping system is used for shaping a homemade high-power excimer laser, and the results show that the measured energy transfer efficiency of the system is 33%, the spot size on the work piece is 100 mm×0.3 mm with the average energy density of 470 mJ·cm-2, and the energy distribution homogeneity of long axis is 93.95%. These results can meet the requirement of annealing technology.