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Updated: Jun 3, 2026
07:12
A Standard and Reliable Method to Fabricate Two-Dimensional Nanoelectronics
Published on: August 28, 2018
From point defects in graphene to two-dimensional amorphous carbon.
J Kotakoski1, A V Krasheninnikov, U Kaiser
1Department of Physics, University of Helsinki, Post Office Box 43, 00014 Helsinki, Finland. jani.kotakoski@iki.fi
Physical Review Letters
|April 8, 2011
Summary
Researchers created the first amorphous two-dimensional material, a one-atom-thick carbon membrane, using electron irradiation. This breakthrough in 2D materials may lead to new electronic devices.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Nanotechnology
Background:
- Crystalline two-dimensional (2D) materials like graphene are well-established.
- The creation of amorphous 2D materials has remained an experimental challenge.
Purpose of the Study:
- To report the first experimental creation of an amorphous 2D material.
- To investigate the formation mechanism and properties of this novel material.
Main Methods:
- Electron irradiation of a carbon membrane.
- In-situ observation of structural transformation.
- First-principles calculations.
Main Results:
- Successfully synthesized an sp2-hybridized, one-atom-thick amorphous carbon membrane with randomly arranged polygons, including four-membered carbon rings.
- Detailed the step-by-step transformation process via nucleation and growth of multivacancy structures.
- Observed that the created domains possess a band gap.
Conclusions:
- The study presents the first amorphous 2D material, expanding the family of 2D materials.
- Provides fundamental insights into carbon bonding and defect dynamics in graphene.
- The band gap in the amorphous material opens possibilities for novel graphene-based electronic devices.
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