基于分区闪耀原理的宽波段闪耀全息光栅设计及研制

Diffraction efficiency is one of the most important performance indicators of gratings. In order to improve the performance of spectroscopic instruments, it is common to propose high diffraction efficiency requirements for gratings over a wide range of wavelengths. In the development of traditional gratings, the parameters such as the blaze angle and groove depth of a single groove are optimized to improve the diffraction efficiency at a fixed wavelength, and it is difficult to meet the requirements of wide band. Aiming at this problem, a design method of wide-band blazed holographic grating based on partition blazed principle is proposed. Firstly, the multi-parameter grating diffraction efficiency data cube in the whole-band range is established, and then the global optimization design method is used to solve the slot parameters of each partition that meets the specific target based on the initial parameters such as the number of partitions, the maximum or minimum partition range, and thus the wide-band range is obtained. Raster etching process parameters that achieve high diffraction efficiency. Finally, the design and processing of the ion beam etching tool that meets the conditions of pattern transfer are performed. Based on the etching parameters of the single blaze angle, the etching process for the same parameter photoresist mask on the same substrate is performed to perform multiple blaze angles. The production of wide band gratings. This project will complete the design, modeling and development of wide-band holographic grating parameters. Under the given constraints, the diffraction efficiency of the whole band can be improved and the requirements of the corresponding spectral instruments can be met.

衍射效率是光栅最重要的一项性能指标，为提升光谱仪器性能，通常对光栅提出在较宽的波段范围内兼具高衍射效率要求。传统光栅研制中，对单一槽形的闪耀角、槽深等参数进行优化设计从而提高固定波长处衍射效率，难以满足宽波段要求。针对该问题，提出一种基于分区闪耀原理的宽波段闪耀全息光栅设计方法。首先建立全波段范围内的多参数光栅衍射效率数据立方，然后基于分区数、最大或最小分区范围等初始参数利用全局优化设计方法求解出满足特定目标的各分区槽形参数，从而获得宽波段范围内达到高衍射效率的光栅刻蚀工艺参数。最后进行满足图形转移条件的离子束刻蚀工装的设计及加工，以单闪耀角的刻蚀参数为基础，进行同一基底上针对同一参数光刻胶掩模的刻蚀工艺研究，进行多闪耀角的宽波段光栅的制作。本项目将完成对宽波段全息光栅参数设计、建模和研制等工作，在给定的约束条件下可以更好地提高全波段的衍射效率，并满足相应光谱仪器的使用条件要求。

全息光栅作为光谱仪器的核心光学元件，其设计制造技术水平直接决定了 光谱仪器的性能。与传统的机械刻划光栅相比，全息光栅具有完全无鬼线、高信噪比、制造周期短、光栅面型多样和易制成大面积等诸多优点。离子束刻蚀技术的发展进一步推动了全息光栅的发展，全息光栅与离子束刻蚀技术的成功 结合，极大地提高了全息光栅的衍射效率。宽波段全息光栅在光谱分析领域具有使仪器结构 简单、使用便捷等独特优势，如何在同一块光栅上制作出不同闪耀角的全息离 子束刻蚀光栅是光栅领域的前沿课题。本文围绕全息光栅掩模图形转移理论模 型及新工艺进行了研究。在分析全息离子束刻蚀物理过程基础上，建立了以特征曲线法为依据的光栅掩模图形转移理论模型，对全息光栅掩模图形转移过程进行数值模拟，并以三角形、矩形、梯形等槽形光栅为例，模拟了光栅槽形的形成过程。提出了宽波段全息光栅槽形参数分段设计方法，给出利用宽波段全息光栅槽形 参数优化光栅衍射效率的计算模型，采用分段、分步离子束刻蚀技术，在同一 光栅基底上分区制作了位相相同但闪耀角不同的宽波段闪耀光栅，研制了 200nm~900nm宽波段全息离子束刻蚀光栅。