多能点X射线透射光栅的制作技术

针对X射线自支撑透射光栅在多能点单色成像光栅谱仪中的应用,采用电子束和光学匹配曝光、微电镀和高密度等离子体刻蚀技术,成功制备了周期为500nm、金吸收体厚度为350nm、占空比接近1∶1,满足三个能点成像需求的2000lp/mm X射线自支撑透射光栅。首先利用电子束光刻和微电镀技术制备金光栅图形,然后采用紫外光刻和微电镀技术制作自支撑结构,最后通过腐蚀体硅和感应耦合等离子体刻蚀聚酰亚胺完成X射线自支撑透射光栅的制作。在电子束光刻中,采用几何校正和高反差电子束抗蚀剂实现了对纳米尺度光栅图形的精确控制。实验结果表明,同一个器件分布的三块光栅占空比合理,栅线平滑,可以满足单能点单色成像谱仪的要求。

Fabrication of Multi-Energy Point X-Ray Transmission Gratings

For the application of the X-ray self-standing transmission gratings in the multi-energy point imaging spectrometer,2 000 lp/mm X-ray self-standing transmission gratings with a period of 500 nm,a gold absorber thickness of 250 nm and the duty cycle nearly 1∶1 were successfully fabricated by the combination process of electron beam lithography,UV lithography,micro-electroplating and inductively coupled plasma etching.Firstly,the gold gratings pattern was fabricated by the e-beam lithography and micro-electroplating technology.Then,the self-stan-ding structure was made by UV lithography and micro-electroplating.Finally,the fabrication of X-ray self-standing transmission gratings was fulfilled by corroding bulk silicon and inductively coupled plasma etching polyimide.It was realized to precisely control the grating pattern with nano-scale by geometric correction and high contrast electron beam resist during the electron beam lithography.The experimental results show that three gratings in the same device,of which the duty cycle is reasonable and the gate line is smooth,can meet the requirements of single-energy point imaging spectrometers.