The gas field ion microscope was used to investigate helium and neon ion beam induced etching of nickel as a candidate technique for extreme ultraviolet (EUV) lithography mask editing. No discernable nickel etching was observed for room temperature helium exposures at 16 and 30 keV in the dose range of 1 x 10(15)-1 x 10(18) He+/cm(2); however, transmission electron microscopy (TEM) revealed subsurface damage to the underlying Mo-Si multilayer EUV mirror. Subsequently, neon beam induced etching at 30 keV was investigated over a similar dose range and successfully removed the entire 50 nm nickel top absorber film at a dose of similar to 3 x 10(17) Ne+/cm(2). Similarly, TEM revealed subsurface damage in the underlying Mo-Si multilayer. To further understand the helium and neon damage, the authors simulated the ion-solid interactions with our EnvizION Monte-Carlo model, which reasonably correlated the observed damage and bubble formation to the nuclear energy loss and the implanted inert gas concentration, respectively. A critical nuclear energy density loss of similar to 80 eV/nm(3) and critical implant concentration of similar to 2.5 x 10(20) atoms/cm(3) have been estimated for damage generation in the multilayer structure. (C) 2014 American Vacuum Society.
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机译:气相离子显微镜用于研究氦和氖离子束诱导的镍蚀刻,将其作为极紫外(EUV)光刻掩模编辑的候选技术。在剂量范围为1 x 10(15)-1 x 10(18)He + / cm(2)的16和30 keV的室温氦气下,未观察到明显的镍蚀刻。然而,透射电子显微镜(TEM)揭示了对下面的Mo-Si多层EUV反射镜的表面损伤。随后,在相似的剂量范围内研究了在30 keV下氖气束诱导的蚀刻,并以类似于3 x 10(17)Ne + / cm(2)的剂量成功去除了整个50 nm镍顶部吸收膜。同样,TEM显示了在下面的Mo-Si多层膜中的地下损伤。为了进一步了解氦气和氖气的损害,作者使用我们的EnvizION蒙特卡洛模型模拟了离子与固体的相互作用,该模型将观察到的损害和气泡形成分别与核能损失和注入的惰性气体浓度合理地关联起来。对于多层结构中的损伤产生,已估算出类似于80 eV / nm(3)的临界核能密度损失和类似于2.5 x 10(20)原子/ cm(3)的临界注入浓度。 (C)2014美国真空学会。
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