标题： 用于复制闪耀反射光栅的衬底共形压印光刻溶胶抗蚀剂收缩的X射线验证 显示英文标题

标题： X-ray verification of sol-gel resist shrinkage in substrate-conformal imprint lithography for a replicated blazed reflection grating

摘要： 通过纳米压印光刻（NIL）制造的表面浮雕光栅容易因抗蚀剂收缩而产生地形畸变。 对于软 X 射线波长（$\lambda \approx 0.5 - 5$~nm）天文学光谱学应用来说，表征这种效应对闪耀衍射效率的影响尤为重要，这类应用需要大量生产大面积光栅副本，且要求表面浮雕具有亚微米级锯齿形轮廓。 一种非常适合此任务的 NIL 变体是基底共形压印光刻（SCIL），它使用由刚性主模板形成的柔性复合压印模，在无机抗蚀剂中压印纳米级特征，该抗蚀剂通过溶胶-凝胶过程热力学固化。 尽管 SCIL 能在压印模退化之前生产数百个压印，并避免了许多与 NIL 中大面积压印相关的弊端，但溶胶-凝胶抗蚀剂的收缩依赖于压印后的固化温度。 通过先进光源 6.3.2 光束线的原子力显微镜和衍射效率测试，研究了这种效应对闪耀响应的影响，针对在 90$^{\circ}$C 下固化的 $\sim$160-nm 周期光栅副本进行了限制。结果显示，与由各向异性湿法刻蚀制备的主光栅相比，闪耀角度减少了 $\sim$2$^{\circ}$。主光栅是在$\langle 311 \rangle$-取向硅中刻蚀而成，其斜面角接近 30$^{\circ}$。 显示英文摘要

摘要： Surface-relief gratings fabricated through nanoimprint lithography (NIL) are prone to topographic distortion induced by resist shrinkage. Characterizing the impact of this effect on blazed diffraction efficiency is particularly important for applications in astrophysical spectroscopy at soft x-ray wavelengths ($\lambda \approx 0.5 - 5$~nm) that call for the mass-production of large-area grating replicas with sub-micron, sawtooth surface-relief profiles. A variant of NIL that lends itself well for this task is substrate-conformal imprint lithography (SCIL), which uses a flexible, composite stamp formed from a rigid master template to imprint nanoscale features in an inorganic resist that cures thermodynamically through a silica sol-gel process. While SCIL enables the production of several hundred imprints before stamp degradation and avoids many of the detriments associated with large-area imprinting in NIL, the sol-gel resist suffers shrinkage dependent on the post-imprint cure temperature. Through atomic force microscopy and diffraction-efficiency testing at beamline 6.3.2 of the Advanced Light Source, the impact of this effect on blaze response is constrained for a $\sim$160-nm-period grating replica cured at 90$^{\circ}$C. Results demonstrate a $\sim$2$^{\circ}$ reduction in blaze angle relative to the master grating, which was fabricated by anisotropic wet etching in $\langle 311 \rangle$-oriented silicon to yield a facet angle close to 30$^{\circ}$.