Achromatic Talbot lithography(ATL)with high resolution has been demonstrated to be an excellent technique for large area periodic nano-fabrication.In this work,the uniformity of pattern distribution in ATL was studied in detail.Two ATL transmission masks with^50%duty cycle in a square lattice were illuminated by a spatial coherent broadband extreme ultraviolet beam with a relative bandwidth of 2.38%.Nonuniform dot size distribution was observed by experiments and finite-difference time-domain simulations.The sum of the two kinds of diffraction patterns,with different lattice directions(45°rotated)and different intensity distributions,results in the final nonuniform pattern distribution.
Huijuan XiaShumin YangLiansheng WangJun ZhaoChaofan XueYanqing WuRenzhong Tai