光学学报, 2008, 28 (7): 1225, 网络出版: 2008-07-04
13.4 nm软X射线干涉光刻透射光栅的优化设计
Optimized Design of Transmission Grating Used for 13.4 nm Soft X-Ray Interference Lithography
干涉光刻 软X射线透射光栅 严格耦合波方法 复折射率 衍射效率 interference lithography soft X-ray transmission grating rigorous coupled-wave method complex refractive index diffraction efficiency
摘要
基于严格的矢量耦合波方法,结合纳米级光栅实际制作工艺,定量分析了在13.4 nm软X射线(TE偏振)正入射条件下,光栅材料、厚度、占空比、梯形浮雕底角大小等因素对光栅一级衍射效率的影响。结果表明,在此波段处,Si3N4、Cr、Au浮雕的相位作用对光栅衍射起重要影响,其中非金属材料Si3N4比金属材料Cr、Au的相位作用更明显。最后优化得到了用Si(或Si3N4)做衬底的Si3N4、Cr、Au光栅,分析结果显示,其一级衍射效率优于目前用于13.4 nm软X射线干涉光刻的Cr、Si3N4复合光栅。
Abstract
Based on the rigorous coupled-wave analysis, considering the actual fabrication processes for nanometer level gratings, the first-order diffraction efficiency was simulated for a normally-incident transmission grating at wavelength of 13.4 nm. The influence on the first-order diffraction efficiency by parameters, such as grating materials, relief thickness, gap/period ratio, and trapezoidal angle on the relief are analyzed quantitatively. The results show at the wavelength, the phase of the relief (Si3N4, Cr, Au) effects grating diffraction greatly. The phase shift of the nonmetallic relief (Si3N4) is found to precede the metallic materials (Cr, Au). After optimization, Si3N4, Cr and Au gratings with Si (Si3N4) substrate are proposed , which have the higher first-order diffraction efficiency than the Cr/Si3N4 compound gratings currently used for soft X-ray interference lithography.
朱伟忠, 吴衍青, 陈敏, 王纳秀, 邰仁忠, 徐洪杰. 13.4 nm软X射线干涉光刻透射光栅的优化设计[J]. 光学学报, 2008, 28(7): 1225. Zhu Weizhong, Wu Yanqing, Chen Min, Wang Naxiu, Tai Renzhong, Xu Hongjie. Optimized Design of Transmission Grating Used for 13.4 nm Soft X-Ray Interference Lithography[J]. Acta Optica Sinica, 2008, 28(7): 1225.