一种X射线成像型平响应低通滤波技术  

A Technology of X-Ray Imaging Flat-Response Low-Pass Filter

作　　者：袁铮[1] 曹柱荣[1] 朱效立[2] 邓博[1] 李晋[1] 杨志文[1] 洪才浩[3] 刘慎业[1] 杨家敏[1] 赵屹东[3] 

机构地区：[1]中国工程物理研究院激光聚变研究中心,四川绵阳621900 [2]中国科学院微电子研究所纳米加工与新器件集成技术实验室,北京100029 [3]中国科学院高能物理研究所,北京100049

出　　处：《光学学报》2016年第5期329-334,共6页Acta Optica Sinica

基　　金：中国工程物理研究院科学技术发展基金(2014B0102010)

摘　　要：提出一种基于掠入射微柱面反射镜阵列的X射线成像型平响应低通滤波技术.根据X射线光学理论,介绍了基于微柱面反射镜阵列的平响应低通滤波原理,分析了元件透射谱的计算方法.基于电子束刻蚀技术在聚酰亚胺衬底上制作了金柱体直径200nm、深度1.3μm、占空比0.393的微柱面镜阵列样品,根据理论计算在2°掠射角时其截止能量为1250eV,响应不平整度为5.7%.利用转角精度优于0.1°的三维精密转角机构,在北京同步辐射装置的4B7B软X射线束线站标定样品在不同掠入射角下的透射率,得到初步标定结果.标定结果显示,在1keV以上的不同能点各曲线均有下降趋势,且角度越大下降能点越偏软,说明掠射角的增大对较高能的X射线具有明显抑制效果.由于电子束刻蚀的技术局限性,样品的深宽比、侧壁垂直度、侧壁粗糙度等参数并未达到理论要求,所以标定结果与理论计算值有一定差异.A X-ray imaging flat-response low-pass filter technology based on grazing incidence micro-cylinder mirror arrays is proposed.According to the X-ray optical theory,the principle of flat-response low-pass filter based on micro-cylinder mirror arrays is introduced and the computational method of the element transmission spectrum is analyzed.A micro-cylinder array sample is fabricated on the substrate of polyimide by electron-beam lithography,with 200 nm column diameter,1.3μm height and 0.393 duty ratio.According to the theoretical calculation,when the glancing angle is 2°,the end-energy is 1250 eV and the unevenness is 5.7%.Transmission of this array is calibrated on 4B7 Bsoft X ray beam line station of Beijing synchrotron radiation facility from several grazing-incidence angles,using a three dimensional precision angle institution of which the angular precision is better than 0.1°.The initial calibration result is attained.Calibration result shows that for all the grazing-incidence angles,the transmission presents on declining curve over 1keV,and the downturn energy decreases as the angle increases.It demonstrates that the increase of glancing angle has an restraint effect on the high-energy X-ray.Because of the electron-beam lithography limits,the depth to width,side wall perpendicularity,side wall roughness and other parameters of the sample can not reach the theory requirement,thus the calibration result has an certain difference from the theoretical calculation.

关 键 词：X射线光学 平响应低通滤波 掠入射 微柱面镜阵列 同步辐射 

分 类 号：O434.19[机械工程—光学工程] O435.1[理学—光学]