软X射线位相型金透射光栅的设计与制作

根据衍射光栅的标量理论，计算并讨论了金透射光栅在软X波段衍射效率对光栅厚度和占宽比的依赖关系.结果表明，选择合适的光栅槽深和占宽比，高达 21.9%的衍射效率可能被获得，远高于振幅型光栅的+1级衍射效率10.14%.通过全息光刻与电镀转移技术制作的位相型金透射光栅由300nm的聚酰亚胺薄膜支撑，光栅槽深200nm，占宽比为0.55，周期为1μm，面积为20mm×5mm.在国家同步辐射装置上，测得其+1级透射衍射效率在波长λ=7.425nm时获得最大值，约为16%. 关键词： 透射位相光栅 全息光刻 电镀

Design and fabrication of gold transmission phase gratings for soft X-rays

The diffraction efficiency of a gold transmission phase grating is simulated as a function of the depth of grooves and the duty cycle on the basis of the scalar diffraction theories. It is shown that the +1 order diffraction efficiency of a transmission phase grating with appropriate groove depth and duty cycle can beup to 21.9% of the incident light，whereas it is no greater than 10% for a conventional amplitude-mode transmission grating. Transmission gratings with area of 20mm×5mm，period of 1μm，duty cycle of 0.55 and 200nm thick gold bars supported by a membrane of 300nm thick polyimide have been fabricated by combining holographic lithography and electroplating. Its diffraction efficiency has been measured in national synchrotron radiation laboratory，and the maximum efficiency in +1 order is about 16% at λ=7.425nm.