Patterning damage mechanisms for 2D crystalline polymers and evaluation for a conjugated imine-based polymer

• Published in: Nanotechnology 2024-08
• Main Authors: Zhang, Bowen, Liu, Xiaohui, Li, Wei, Clausner, André, Conzendorf, Sylvia, Liu, Jinxin, Posseckardt, Juliane, Jost, Birgit, Dong, Renhao, Feng, Xinliang, Liao, Zhongquan, Zschech, Ehrenfried
• Format: Article
• Language: English
• ISSN: 1361-6528
• DOI: 10.1088/1361-6528/ad6e8a

High-quality patterning determines the properties of patterned emerging two-dimensional (2D) conjugated polymers which is essential for potential applications in future electronic nanodevices. However, the suitable patterning method for 2D polymers is yet concluded because it's still challenging to gain comprehensive understanding of their damage mechanisms by visualizing the structural modification during patterning process. Here, the damage mechanisms during patterning of 2D polymers, induced by various patterning methods, are unveiled based on a systematic study of structural damage and edge morphology on an imine-based 2D polymer (polyimine). Patterning using focused electron beam, focused ion beam (FIB) and mechanical carving is evaluated. Focused electron beam successively introduces sputtering effect, knock-on displacement damage and massive radiolysis effect as increasing the electron dose from 9.46×107 e-/nm2 to 1.14×1010 e-/nm2. The successful pattering is enabled by knock-on damage while impeded by carbon contamination when beyond a critical sample thickness. FIB creates current-dependent edge morphologies and extensive damage from the ion implantation caused by the tail of unfocused beam. A precisely controlled tip can tear the polyimine film through grain boundaries and in hence create the patterning edge with suitable edge roughness for certain application senarios when the beam damage is avoided. Taking structural damage and the resulting quantitative edge roughness into consideration, this study provides a detailed instruction on the proper patterning techniques for 2D crystalline polymers and paves the way for tailored intrinsic properties and device fabrication using these novel materials.&#xD.