Atomically thin device shows tunable electrical behavior not previously realized in conventional electronics

Oct 21, 2013

As electronics approach the atomic scale, researchers are increasingly successful at developing atomically thin, virtually two-dimensional materials that could usher in the next generation of computing. Integrating these materials to create necessary circuits, however, has remained a challenge.

Northwestern University researchers have now taken a significant step toward fabricating complex nanoscale electronics. By integrating two atomically thin – molybdenum disulfide and carbon nanotubes—they have created a p-n diode, an interface between two types of semiconducting materials.

"The p-n junction diode is among the most ubiquitous components of modern electronics," said Mark Hersam, Bette and Neison Harris Chair in Teaching Excellence in the Department of Materials Science and Engineering at Northwestern's McCormick School of Engineering and Applied Science and director of the Northwestern University Materials Research Center. "By creating this device using atomically thin materials, we not only realize the benefits of conventional diodes but also achieve the ability to electronically tune and customize the device characteristics. We anticipate that this work will enable new types of electronic functionality and could be applied to the growing number of emerging two-dimensional materials."

The isolation over the past decade of atomically thin two-dimensional crystals—such as graphene, a single-atom-thick carbon lattice—has prompted researchers to stack two or more distinct two-dimensional materials to create high-performance, ultrathin electronic devices. While significant progress has been made in this direction, one of the most important —the p-n junction diode—has been notably absent.

Among the most widely used electronic structures, the p-n junction diode forms the basis of a number of technologies, including solar cells, light-emitting diodes, photodetectors, computers, and lasers.

In addition to its novel electronic functionality, the p-n heterojunction is also highly sensitive to light. This attribute has allowed the authors to fabricate and demonstrate an ultrafast photodetector with an electronically tunable wavelength response.

The research, "Gate-Tunable Carbon Nanotube-MoS2 Heterojunction p-n Diode," was published October 21 in the Proceedings of the National Academy of Sciences.

Explore further: All directions are not created equal for nanoscale heat sources

More information: Gate-tunable carbon nanotube–MoS2 heterojunction p-n diode, www.pnas.org/cgi/doi/10.1073/pnas.1317226110

Related Stories

Playing Lego on an atomic scale

Jul 25, 2013

In a perspective review written for Nature, Sir Andre and Dr Irina Grigorieva, from The University of Manchester, discuss how layered materials can be split into isolated atomic planes and then reassembled ...

Densest array of carbon nanotubes grown to date

Sep 20, 2013

Carbon nanotubes' outstanding mechanical, electrical and thermal properties make them an alluring material to electronics manufacturers. However, until recently scientists believed that growing the high density ...

Recommended for you

New absorber will lead to better biosensors

15 hours ago

Biological sensors, or biosensors, are like technological canaries in the coalmine. By converting a biological response into an optical or electrical signal, they can alert us to dangers in our external and internal environments. ...

Ultrafast remote switching of light emission

Sep 30, 2014

Researchers from Eindhoven University of Technology can now for the first time remotely control a miniature light source at timescales of 200 trillionth of a second. They published the results on Sept. 2014 ...

Nanotube cathode beats large, pricey laser

Sep 30, 2014

Scientists are a step closer to building an intense electron beam source without a laser. Using the High-Brightness Electron Source Lab at DOE's Fermi National Accelerator Laboratory, a team led by scientist ...

User comments : 0