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
Vortex laser offers hope for Moore's Law
29.07.2016 | University at Buffalo
Ultra-flat circuits will have unique properties
26.07.2016 | Rice University
Transparent electronics devices are present in today’s thin film displays, solar cells, and touchscreens. The future will bring flexible versions of such devices. Their production requires printable materials that are transparent and remain highly conductive even when deformed. Researchers at INM – Leibniz Institute for New Materials have combined a new self-assembling nano ink with an imprint process to create flexible conductive grids with a resolution below one micrometer.
To print the grids, an ink of gold nanowires is applied to a substrate. A structured stamp is pressed on the substrate and forces the ink into a pattern. “The...
A new Fraunhofer MEVIS method conveys medical interrelationships quickly and intuitively with innovative visualization technology
On the monitor, a brain spins slowly and can be examined from every angle. Suddenly, some sections start glowing, first on the side and then the entire back of...
Researchers at the U.S. Department of Energy's (DOE) Ames Laboratory have discovered an unusual property of purple bronze that may point to new ways to achieve high temperature superconductivity.
While studying purple bronze, a molybdenum oxide, researchers discovered an unconventional charge density wave on its surface.
Munich Physicists have developed a novel electron microscope that can visualize electromagnetic fields oscillating at frequencies of billions of cycles per second.
Temporally varying electromagnetic fields are the driving force behind the whole of electronics. Their polarities can change at mind-bogglingly fast rates, and...
Breakup of continents with two speed: Continents initially stretch very slowly along the future splitting zone, but then move apart very quickly before the onset of rupture. The final speed can be up to 20 times faster than in the first, slow extension phase.phases
Present-day continents were shaped hundreds of millions of years ago as the supercontinent Pangaea broke apart. Derived from Pangaea’s main fragments Gondwana...
29.07.2016 | Event News
15.07.2016 | Event News
15.07.2016 | Event News
29.07.2016 | Power and Electrical Engineering
29.07.2016 | Life Sciences
29.07.2016 | Event News