Oliva M, Harzendorf T, Michaelis D, Zeitner U D, Tünnermann A
Fraunhofer Institute for Applied Optics and Precision Engineering, Albert-Einstein-Strasse 7, 07745 Jena, Germany.
Opt Express. 2011 Jul 18;19(15):14735-45. doi: 10.1364/OE.19.014735.
In this paper we present a novel technological approach for the fabrication of multilevel gratings in the resonance domain. A coded chromium mask is used to avoid alignment errors in electron beam lithography, which typically occur within the standard multistep binary micro-optics technology. The lateral features of all phase levels of the grating are encoded in a single chromium mask. The final profile of the structure is obtained by selective etching process for each level. This new technological method is applied for the fabrication of two different three-level gratings in resonance domain. The corresponding optical response as well as structural characterizations are presented and discussed. In particular, a first order diffraction efficiency of 90% is demonstrated for a grating period twice the wavelength at normal incidence.
在本文中，我们提出了一种在共振域制造多级光栅的新颖技术方法。使用编码铬掩模来避免电子束光刻中通常在标准多步二元微光学技术中出现的对准误差。光栅所有相位级别的横向特征都编码在单个铬掩模中。通过对每个级别进行选择性蚀刻工艺获得结构的最终轮廓。这种新技术方法应用于在共振域制造两种不同的三级光栅。给出并讨论了相应的光学响应以及结构表征。特别是，对于在正常入射下光栅周期为波长两倍的情况，展示了90%的一阶衍射效率。
