Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Layered '2-D nanocrystals' promising new semiconductor

17.04.2013
Researchers are developing a new type of semiconductor technology for future computers and electronics based on "two-dimensional nanocrystals" layered in sheets less than a nanometer thick that could replace today's transistors.
The layered structure is made of a material called molybdenum disulfide, which belongs to a new class of semiconductors - metal di-chalogenides - emerging as potential candidates to replace today's technology, complementary metal oxide semiconductors, or CMOS.

New technologies will be needed to allow the semiconductor industry to continue advances in computer performance driven by the ability to create ever-smaller transistors. It is becoming increasingly difficult, however, to continue shrinking electronic devices made of conventional silicon-based semiconductors.

"We are going to reach the fundamental limits of silicon-based CMOS technology very soon, and that means novel materials must be found in order to continue scaling," said Saptarshi Das, who has completed a doctoral degree, working with Joerg Appenzeller, a professor of electrical and computer engineering and scientific director of nanoelectronics at Purdue's Birck Nanotechnology Center. "I don't think silicon can be replaced by a single material, but probably different materials will co-exist in a hybrid technology."

The nanocrystals are called two-dimensional because the materials can exist in the form of extremely thin sheets with a thickness of 0.7 nanometers, or roughly the width of three or four atoms. Findings show that the material performs best when formed into sheets of about 15 layers with a total thickness of 8-12 nanometers. The researchers also have developed a model to explain these experimental observations.

Findings are appearing this month as a cover story in the journal Rapid Research Letters. The paper was co-authored by Das and Appenzeller, who also have co-authored a paper to be presented during the annual Device Research Conference at the University of Notre Dame from June 23-26.

"Our model is generic and, therefore, is believed to be applicable to any two-dimensional layered system," Das said.

Molybdenum disulfide is promising in part because it possesses a bandgap, a trait that is needed to switch on and off, which is critical for digital transistors to store information in binary code.
Analyzing the material or integrating it into a circuit requires a metal contact. However, one factor limiting the ability to measure the electrical properties of a semiconductor is the electrical resistance in the contact. The researchers eliminated this contact resistance using a metal called scandium, allowing them to determine the true electronic properties of the layered device. Their results have been published in the January issue of the journal Nano Letters with doctoral students Hong-Yan Chen and Ashish Verma Penumatcha as the other co-authors.

Transistors contain critical components called gates, which enable the devices to switch on and off and to direct the flow of electrical current. In today's chips, the length of these gates is about 14 nanometers, or billionths of a meter.

The semiconductor industry plans to reduce the gate length to 6 nanometers by 2020. However, further size reductions and boosts in speed are likely not possible using silicon, meaning new designs and materials will be needed to continue progress. The research was funded by the National Science Foundation.

Writer: Emil Venere, 765-494-4709, venere@purdjue.edu

Sources: Saptarshi Das, sdas@purdue.edu
Joerg Appenzeller, 765 494-1076, appenzeller@purdue.edu

Related webiste:
Network for Computational Nanotechnology

Note to Journalists: An electronic copy of the research paper is available from Emil Venere, 765-494-4709, venere@purdue.edu

Emil Venere | EurekAlert!
Further information:
http://www.purdue.edu

More articles from Power and Electrical Engineering:

nachricht Engineers program tiny robots to move, think like insects
15.12.2017 | Cornell University

nachricht Electromagnetic water cloak eliminates drag and wake
12.12.2017 | Duke University

All articles from Power and Electrical Engineering >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: First-of-its-kind chemical oscillator offers new level of molecular control

DNA molecules that follow specific instructions could offer more precise molecular control of synthetic chemical systems, a discovery that opens the door for engineers to create molecular machines with new and complex behaviors.

Researchers have created chemical amplifiers and a chemical oscillator using a systematic method that has the potential to embed sophisticated circuit...

Im Focus: Long-lived storage of a photonic qubit for worldwide teleportation

MPQ scientists achieve long storage times for photonic quantum bits which break the lower bound for direct teleportation in a global quantum network.

Concerning the development of quantum memories for the realization of global quantum networks, scientists of the Quantum Dynamics Division led by Professor...

Im Focus: Electromagnetic water cloak eliminates drag and wake

Detailed calculations show water cloaks are feasible with today's technology

Researchers have developed a water cloaking concept based on electromagnetic forces that could eliminate an object's wake, greatly reducing its drag while...

Im Focus: Scientists channel graphene to understand filtration and ion transport into cells

Tiny pores at a cell's entryway act as miniature bouncers, letting in some electrically charged atoms--ions--but blocking others. Operating as exquisitely sensitive filters, these "ion channels" play a critical role in biological functions such as muscle contraction and the firing of brain cells.

To rapidly transport the right ions through the cell membrane, the tiny channels rely on a complex interplay between the ions and surrounding molecules,...

Im Focus: Towards data storage at the single molecule level

The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.

Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

AKL’18: The opportunities and challenges of digitalization in the laser industry

07.12.2017 | Event News

 
Latest News

Engineers program tiny robots to move, think like insects

15.12.2017 | Power and Electrical Engineering

One in 5 materials chemistry papers may be wrong, study suggests

15.12.2017 | Materials Sciences

New antbird species discovered in Peru by LSU ornithologists

15.12.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>