Investigation on near-plane varied-line-spacing gratings made by electron beam lithography and near field holography

电子束光刻和近场全息近平面变线距光栅研究

• 批准号: 254170536
• 负责人: Dr. Ernst-Bernhard Kley
• 金额: --
• 依托单位: Institut für Angewandte Physik
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2014
• 资助国家: 德国
• 起止时间: 2013-12-31 至 2016-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/254170536?language=en
• 关键词: Investigation; near; plane; varied; line

Varied-line-spacing gratings (VLSGs) are continuously being developed for synchrotron radiation, plasma diagnosis, and other applications with their advantages of high resolution, aberration correction, and simple scanning mechanisms. VLSGs have been fabricated by either mechanical ruling or holographic ion beam etching. Mechanical ruling suffers from ghost lines, background scattering and rough facets. In contrast, holographically etched VLSGs overcome the above drawbacks. Nevertheless, the optical configuration for holographic exposure is complex for VLSGs and is considered as less flexible in the generation of the period distribution than the EBL method. At present, a precise and fast micro- and nano-fabrication technique for large aperture VLSGs is still challenging, especially for soft x-ray VLSGs with a high density and small density increment. Therefore, we propose an innovative combination of high-end electron beam lithography and optical near field holography (EBL-NFH) for the development of VLSGs with an unprecedented step period increment of ~ 0.1 nm on a long substrate. In its essence, first an initial and reusable fused silica mask of a VLSG is fabricated by EBL. Afterwards, the pattern of the fused silica mask is replicated and transferred to a photo resist layer by NFH, such that a photo resist mask is obtained that can be copied into the substrate. Finally, an optimized VLSG will be fabricated after one or a few feedback cycles via the photo resist mask in NFH process. To our knowledge - this method has not yet been applied at least to the EUV and soft x-ray regime, with its needs for high accuracy and spatial resolution in the copy process. The most important and time-consuming process in the project is presumably the EBL fabrication. Hence it is crucial to realize a reusable initial mask by EBL. The combination of EBL with NFH achieves this aim exactly. Compared to other pattern transfer techniques, the advantage of NFH is that it not only transfers the binary density distribution of the mask, but may also control the photo resist profile according to its design requirement. Our goal is to develop a flexible, convenient and high-efficient micro- and nano-production method for high-precision VLSGs, to improve their optical properties and to extend the application range of the EBL-NFH technique. Keywords: micro- & nano-production; VLSG; electron beam lithography; near field holography; soft x-rays.

变线距光栅（VLSGs）以其高分辨率、像差校正和简单的扫描机制等优点，在同步辐射、等离子体诊断等领域得到了广泛的应用。VLSG已经通过机械刻划或全息离子束蚀刻制造。机械划线会受到鬼线、背景散射和粗糙刻面的影响。相比之下，全息蚀刻的VLSG克服了上述缺点。然而，全息曝光的光学配置对于VLSG是复杂的，并且被认为在周期分布的生成方面比EBL方法灵活性更低。目前，大口径VLSGs的精确和快速的微米和纳米制造技术仍然具有挑战性，特别是对于具有高密度和小密度增量的软X射线VLSGs。因此，我们提出了一种创新的高端电子束光刻和光学近场全息（EBL-NFH）的组合，用于VLSGs的开发，其在长衬底上具有前所未有的~ 0.1 nm的步进周期增量。本质上，首先由EBL制造VLSG的初始和可重复使用的熔融石英掩模。然后，通过NFH将熔融石英掩模的图案复制并转移到光致抗蚀剂层，从而获得可以复制到基板中的光致抗蚀剂掩模。最后，在一个或几个反馈周期后，通过光致抗蚀剂掩模在NFH工艺中制造优化的VLSG。据我们所知，这种方法至少还没有应用于EUV和软X射线领域，因为它需要在复制过程中具有高精度和空间分辨率。项目中最重要和最耗时的过程可能是EBL制造。因此，利用EBL实现可重用的初始掩码是至关重要的。EBL与NFH的结合正好达到了这一目的。与其他图形转移技术相比，NFH的优点是它不仅可以转移掩模的二进制密度分布，而且还可以根据其设计要求控制光刻胶的轮廓。我们的目标是开发一种灵活、方便、高效的高精度VLSG微纳米制备方法，以改善其光学性能，并扩大EBL-NFH技术的应用范围。关键词：微纳制程;超大型雷射;电子束微影;近场全像术;软x光。

项目成果

Reducing Rowland ghosts in diffraction gratings by dynamic exposure near-field holography.

通过动态曝光近场全息术减少衍射光栅中的罗兰鬼影

• DOI: 10.1364/ol.43.000811
• 发表时间: 2018
• 期刊: Optics letters
• 影响因子: 3.6
• 作者: D. Lin;H. Chen;Z. Liu;K. Dietrich;S. Kroker;T. Käsebier;Y. Liu;E. Kley;Y. Hong
• 通讯作者: Y. Hong