The formation of electrically conducting ‘nanoroads’ on atomically thin semiconductor nanosheets enables the integration of electronic components.
Two-dimensional sheets of electronic materials, such as graphene, show promise for practical nanoelectronics applications, including transparent electronic circuits used in electronic displays.
Conducting ‘nanoroads’ on the surface of nanosheets of molybdenum disulfide could underpin integrated electronics on this ultrathin material.
Molybdenum disulfide (MoS2) is of particular interest because, unlike metallic graphene, it is semiconducting, like silicon — the semiconductor that underpins today’s computer technology.
Now, Yongqing Cai from the A*STAR Institute of High Performance Computing in Singapore, with colleagues from China and the United States, has calculated that, by adding hydrogen to a MoS2 surface, regions of the surface can be converted into metallic ‘roads’.
These roads can transport electrical charges between different areas of a MoS2 nanosheet, enabling the fabrication of integrated electronic circuits(1).
Computer chips require both semiconductors and metals. Semiconductors (typically silicon) are the basis for electronic components such as transistors, whereas metals (generally copper or gold) are used for wires that transport electrical charges around a chip. One advantage of using two-dimensional sheets such as MoS2 is that semiconductors and metals can be integrated on the same sheet, facilitating the development of nanoscale computer chips.
For this to become a reality, the semiconducting properties of a MoS2 sheet need to be modified to enable some areas of the sheet to become metallic and hence electrically conducting. Cai dubs these regions ‘nanoroads’.
“The design of conductive nanoroads on two-dimensional nanosheets — in a way that doesn’t compromise their structural integrity — is critical for transporting electrical charges and to create reliable, highly conducting channels for nanoelectronics applications,” explains Cai.
MoS2 has to be modified before it can conduct electricity, since it requires additional atoms to be able to transport electrical charges. The researchers simulated the effects of adding hydrogen atoms to the surface of a MoS2 sheet and found that MoS2 will become metallic in areas where hydrogen atoms bond to its surface.
They showed that adding lines or chains of hydrogen atoms to the surface created metallic strips. The researchers’ calculations reveal that these strips, or nanoroads, are reliable electrical conductors, and, importantly, they do not damage the structure of the underlying sheets.
In terms of practical implementation, the technology already exists for depositing hydrogen on semiconductor nanosheets: hydrogen has been deposited on other two-dimensional sheets, including graphene. Before MoS2 sheets can be used to produce components such as transistors, a method for producing electron-deficient regions needs to be developed. Once this practical challenge has been addressed, the way will be open to successfully using MoS2 in integrated electronic applications.
1. Cai, Y., Bai, Z., Pan, H., Feng, Y. P., Yakobson, B. I. & Zhang, Y.-W. Constructing metallic nanoroads on a MoS2 monolayer via hydrogenation. Nanoscale 6, 1691–1697 (2014).
Lee Swee Heng | Research SEA News
On the crest of the wave: Electronics on a time scale shorter than a cycle of light
30.07.2015 | Universität Regensburg
Ultra-Thin Hollow Nanocages Could Reduce Platinum Use in Fuel Cell Electrodes
27.07.2015 | Georgia Institute of Technology
Glacier decline in the first decade of the 21st century has reached a historical record, since the onset of direct observations. Glacier melt is a global phenomenon and will continue even without further climate change. This is shown in the latest study by the World Glacier Monitoring Service under the lead of the University of Zurich, Switzerland.
The World Glacier Monitoring Service, domiciled at the University of Zurich, has compiled worldwide data on glacier changes for more than 120 years. Together...
Using ultracold atoms trapped in light crystals, scientists from the MPQ, LMU, and the Weizmann Institute observe a novel state of matter that never thermalizes.
What happens if one mixes cold and hot water? After some initial dynamics, one is left with lukewarm water—the system has thermalized to a new thermal...
Physicists from Regensburg and Marburg, Germany have succeeded in taking a slow-motion movie of speeding electrons in a solid driven by a strong light wave. In the process, they have unraveled a novel quantum phenomenon, which will be reported in the forthcoming edition of Nature.
The advent of ever faster electronics featuring clock rates up to the multiple-gigahertz range has revolutionized our day-to-day life. Researchers and...
Researchers have developed an ultrafast light-emitting device that can flip on and off 90 billion times a second and could form the basis of optical computing.
Joint BioEnergy Institute study identifies bacterial protein that is key to protecting rice against bacterial blight
A bacterial signal that when recognized by rice plants enables the plants to resist a devastating blight disease has been identified by a multi-national team...
23.07.2015 | Event News
10.07.2015 | Event News
25.06.2015 | Event News
03.08.2015 | Materials Sciences
03.08.2015 | Life Sciences
03.08.2015 | Life Sciences