Lugier O, Thakur N, Wu L, Vockenhuber M, Ekinci Y, Castellanos S
Advanced Research Center for Nanolithography, Science Park 106, 1098XG Amsterdam, The Netherlands.
Paul Scherrer Institute, Forschungstrasse 111, 5232 Villigen, Switzerland.
ACS Appl Mater Interfaces. 2021 Sep 15;13(36):43777-43786. doi: 10.1021/acsami.1c13667. Epub 2021 Aug 31.
The fabrication of integrated circuits with ever smaller (sub-10 nm) features poses fundamental challenges in chemistry and materials science. As smaller nanostructures are fabricated, thinner layers of materials are required, and surfaces and interfaces gain a more important role in the formation of nanopatterns. We present a new bottom-up approach in which we use the high optical resolution offered by extreme ultraviolet (EUV) lithography to print patterns on self-assembled monolayers (SAMs). Upon radiation, low-energy electrons induce chemical changes in the SAM so that the projected image is transferred to the substrate surface. We use the chemical differences between exposed and unexposed regions to promote a selective growth of hybrid structures that can act as an etch-resistant layer for further pattern transfer or can be used as functional nanostructures. The EUV doses required to promote selective growth on exposed areas are close to industrial requirements. Furthermore, this method allows for the independent tuning of different steps in the EUV lithography process (photo-induced chemistry, spatially resolved chemical contrast, and formation of nanopatterns), an advantage over current resists, in which the same material plays all roles.
制造具有越来越小（小于10纳米）特征尺寸的集成电路在化学和材料科学领域带来了根本性挑战。随着更小纳米结构的制造，所需材料层变薄，表面和界面在纳米图案形成中发挥着更为重要的作用。我们提出了一种新的自下而上的方法，即利用极紫外（EUV）光刻提供的高光学分辨率在自组装单分子层（SAMs）上打印图案。在辐射作用下，低能电子会在SAM中引发化学变化，从而将投影图像转移到基底表面。我们利用曝光区域和未曝光区域之间的化学差异来促进混合结构的选择性生长，这些混合结构既可以作为抗蚀刻层用于进一步的图案转移，也可以用作功能性纳米结构。在曝光区域促进选择性生长所需的EUV剂量接近工业要求。此外，这种方法能够独立调节EUV光刻过程中的不同步骤（光致化学、空间分辨化学对比度和纳米图案形成），这是相对于当前光刻胶的一个优势，因为在当前光刻胶中，同一材料扮演着所有角色。
