Researchers find a way to integrate two two-dimensional materials into a single electronic device

May 22, 2014 by Bob Yirka, report

Credit: ACS
( —Researchers working at the Massachusetts Institute of Technology have found a way to integrate two different two-dimensional materials in one single electronic device. In their paper published in the journal Nano Letters, the team describes how they used both graphene and molybdenum disulfide (MoS2) to create a single circuit.

Two dimensional materials (so named because they are just one atom thick) have created a lot of buzz in the electronics community because of their unique electronic properties. Scientists hope to use them to create smaller, more efficient devices. The two main materials that have captured the attention of the research world are graphene (a sheet of carbon) and MoS2. Both have shown promise, but each has its limitations. To take advantage of what each does well, and to avoid the disadvantages, researchers have looked to joining the two on a single circuit. In this new effort the team at MIT is reporting that they've done just that, creating large-scale .

Getting the two materials to cooperate was no easy feat. They started by growing samples of MoS2 and using . The MoS2 was then etched to fashion it into channels, followed by a process that caused aluminum oxide (Al2O3) to form on its surface. Graphene sheets were then applied to the channel, cut with oxygen plasma to form gate electrodes and source drains. In the final result, the Al2O3 serves to protect the MoS2 allowing the circuit to run as designed.

The researchers believe their fabrication process could be used to allow for integrating many types of two-dimensional materials, allowing for the creation of whole new device types, e.g. lasers, tunneling microscopes and a variety of transistors. An additional plus, they note, is that because the finished products are exceptionally thin, they can be bent to allow for the creation of circuits of virtually any shape. The circuits are also transparent, which means they could likely be used for new types of personal technology devices (skin patches or those that can be sewn into clothes, for example) or as a part of hidden sensors. The team plans to next work on integrating insulating layers onto their tiny circuits, allowing for the creation of even more exotic circuitry.

Explore further: Scientists probe the next generation of 2-D materials

More information: Graphene/MoS2 Hybrid Technology for Large-Scale Two-Dimensional Electronics, Nano Lett., Article ASAP. DOI: 10.1021/nl404795z

Two-dimensional (2D) materials have generated great interest in the past few years as a new toolbox for electronics. This family of materials includes, among others, metallic graphene, semiconducting transition metal dichalcogenides (such as MoS2), and insulating boron nitride. These materials and their heterostructures offer excellent mechanical flexibility, optical transparency, and favorable transport properties for realizing electronic, sensing, and optical systems on arbitrary surfaces. In this paper, we demonstrate a novel technology for constructing large-scale electronic systems based on graphene/molybdenum disulfide (MoS2) heterostructures grown by chemical vapor deposition. We have fabricated high-performance devices and circuits based on this heterostructure, where MoS2 is used as the transistor channel and graphene as contact electrodes and circuit interconnects. We provide a systematic comparison of the graphene/MoS2 heterojunction contact to more traditional MoS2-metal junctions, as well as a theoretical investigation, using density functional theory, of the origin of the Schottky barrier height. The tunability of the graphene work function with electrostatic doping significantly improves the ohmic contact to MoS2. These high-performance large-scale devices and circuits based on this 2D heterostructure pave the way for practical flexible transparent electronics.

Related Stories

Scientists probe the next generation of 2-D materials

April 3, 2014

As the properties and applications of graphene continue to be explored in laboratories all over the world, a growing number of researchers are looking beyond the one-atom-thick layer of carbon for alternative materials that ...

Fantastic flash memory combines graphene and molybdenite

March 19, 2013

Swiss scientists have combined two materials with advantageous electronic properties—graphene and molybdenite—into a flash memory prototype that is very promising in terms of performance, size, flexibility and energy ...

Scalable CVD process for making 2-D molybdenum diselenide

April 8, 2014

( —Nanoengineering researchers at Rice University and Nanyang Technological University in Singapore have unveiled a potentially scalable method for making one-atom-thick layers of molybdenum diselenide—a highly ...

New graphene-type material created

May 22, 2014

( —Scientists at the University of Liverpool have created a new material, related to graphene, which has the potential to improve transistors used in electronic devices.

Recommended for you

Researchers engineer a tougher fiber

February 22, 2019

North Carolina State University researchers have developed a fiber that combines the elasticity of rubber with the strength of a metal, resulting in a tougher material that could be incorporated into soft robotics, packaging ...

A quantum magnet with a topological twist

February 22, 2019

Taking their name from an intricate Japanese basket pattern, kagome magnets are thought to have electronic properties that could be valuable for future quantum devices and applications. Theories predict that some electrons ...


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.