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Updated: Feb 15, 2026
09:25
Fabricating van der Waals Heterostructures with Precise Rotational Alignment
Published on: July 5, 2019
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Self-Aligned van der Waals Heterojunction Diodes and Transistors
Vinod K Sangwan1, Megan E Beck1, Alex Henning1
1Department of Materials Science and Engineering, ‡Department of Chemistry, and §Department of Electrical Engineering and Computer Science, Northwestern University , Evanston, Illinois 60208, United States.
Nano Letters
|February 1, 2018
Summary
A novel self-aligned fabrication method enables the creation of advanced van der Waals electronic devices. This technique allows for the development of highly efficient transistors and diodes with nanoscale precision.
Area of Science:
- Materials Science
- Nanotechnology
- Electronics Engineering
Background:
- Van der Waals materials offer unique electronic properties for next-generation devices.
- Fabrication of nanoscale electronic devices with precise control remains a challenge.
Purpose of the Study:
- To develop a general, self-aligned fabrication scheme for diverse van der Waals electronic devices.
- To demonstrate the capability of this method for creating advanced transistors and heterojunction diodes.
Main Methods:
- A self-aligned fabrication process utilizing van der Waals materials and heterojunctions.
- Finite-element device simulations to elucidate operating principles.
- Photolithography on large-area MoS2 films for scalability.
Main Results:
- Fabrication of source-gated transistors in MoS2 with 135 nm channel lengths and near-ideal saturation.
- Development of dual-gated van der Waals p-n heterojunction diodes with complete electrostatic control.
- Demonstration of scalability through sub-100 nm self-aligned transistors and various device types.
Conclusions:
- The self-aligned fabrication scheme is versatile and scalable for van der Waals electronics.
- This method facilitates the integration of van der Waals heterojunction devices into complex systems.
- Provides design rules for future self-aligned electronic devices.
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