Saifullah Mohammad S M, Asbahi Mohamed, Neo Darren C J, Mahfoud Zackaria, Tan Hui Ru, Ha Son Tung, Dwivedi Neeraj, Dutta Tanmay, Bin Dolmanan Surani, Aabdin Zainul, Bosman Michel, Ganesan Ramakrishnan, Tripathy Sudhiranjan, Hasko David G, Valiyaveettil Suresh
Laboratory for Micro and Nanotechnology, Paul Scherrer Institute, 5232 Villigen PSI, Switzerland.
Interuniversity Microelectronics Centre (IMEC), Kapeldreef 75, 3001 Leuven, Belgium.
Nano Lett. 2022 Sep 28;22(18):7432-7440. doi: 10.1021/acs.nanolett.2c02339. Epub 2022 Sep 7.
It has been long known that low molecular weight resists can achieve a very high resolution, theoretically close to the probe diameter of the electron beam lithography (EBL) system. Despite technological improvements in EBL systems, the advances in resists have lagged behind. Here we demonstrate that a low-molecular-mass single-source precursor resist (based on cadmium(II) ethylxanthate complexed with pyridine) is capable of a achieving resolution (4 nm) that closely matches the measured probe diameter (∼3.8 nm). Energetic electrons enable the top-down radiolysis of the resist, while they provide the energy to construct the functional material from the bottom-up─unit cell by unit cell. Since this occurs only within the volume of resist exposed to primary electrons, the minimum size of the patterned features is close to the beam diameter. We speculate that angstrom-scale patterning of functional materials is possible with single-source precursor resists using an aberration-corrected electron beam writer with a spot size of ∼1 Å.
长期以来，人们都知道低分子量抗蚀剂能够实现非常高的分辨率，理论上接近电子束光刻（EBL）系统的探针直径。尽管EBL系统在技术上有所改进，但抗蚀剂的进展却滞后了。在此，我们证明一种低分子量单源前驱体抗蚀剂（基于与吡啶络合的乙基黄原酸镉（II））能够实现与测量的探针直径（约3.8纳米）紧密匹配的分辨率（4纳米）。高能电子使抗蚀剂能够进行自上而下的辐射分解，同时它们提供能量以自下而上逐个晶胞地构建功能材料。由于这仅发生在暴露于初级电子的抗蚀剂体积内，图案化特征的最小尺寸接近束直径。我们推测，使用光斑尺寸约为1埃的像差校正电子束写入器，单源前驱体抗蚀剂有可能实现功能材料的埃级图案化。
