Patterning damage mechanisms for two-dimensional crystalline polymers and evaluation for a conjugated imine-based...

Area of Science:

• Materials Science
• Nanotechnology
• Polymer Chemistry

Background:

• High-quality patterning of emerging two-dimensional (2D) conjugated polymers is vital for advanced electronic nanodevices.
• A comprehensive understanding of damage mechanisms during patterning is lacking for 2D polymers, hindering method selection.

Purpose of the Study:

• To unveil damage mechanisms during the patterning of 2D polymers using various techniques.
• To systematically study structural damage and edge morphology in an imine-based 2D polymer (polyimine).

Main Methods:

• Evaluation of patterning using focused electron beam, focused ion beam (FIB), and mechanical carving.
• Analysis of structural modifications and edge morphology induced by different patterning methods.
• Correlation of electron dose with sputtering, knock-on displacement, and radiolysis effects.

Main Results:

• Focused electron beam induces sputtering, knock-on damage (enabling patterning), and radiolysis, with carbon contamination impeding patterning beyond critical thickness.
• FIB results in current-dependent edge morphologies and ion implantation damage from unfocused beam tails.
• Mechanical carving, when beam damage is avoided, can create suitable edge roughness by tearing through grain boundaries.

Conclusions:

• This study provides detailed instructions for proper patterning techniques for 2D crystalline polymers.
• Understanding damage mechanisms and edge roughness is key for tailored intrinsic properties and device fabrication.
• The findings pave the way for optimized fabrication of 2D polymer-based electronic nanodevices.