Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Ultra-thin ferroelectric material for next-generation electronics

12.10.2016

'Ferroelectric' materials can switch between different states of electrical polarization in response to an external electric field. This flexibility means they show promise for many applications, for example in electronic devices and computer memory. Current ferroelectric materials are highly valued for their thermal and chemical stability and rapid electro-mechanical responses, but creating a material that is scalable down to the tiny sizes needed for technologies like silicon-based semiconductors (Si-based CMOS) has proven challenging.

Now, Hiroshi Funakubo and co-workers at the Tokyo Institute of Technology, in collaboration with researchers across Japan, have conducted experiments to determine the ferroelectric properties of an inorganic compound called hafnium oxide (HfO2) for the first time. Crucially, the crystal structure of HfO2 allows it to be deposited in ultra-thin films, meaning it may prove invaluable for next-generation technologies.


Scientists at Tokyo Institute of Technology have demonstrated the potential of a new, thin-film ferroelectric material that could improve the performance of next-generation sensors and semi-conductors.

Credit: Tokyo Institute of Technology

Ferroelectric properties stem from the shape and structure of the crystal used. The team knew that an 'orthorhombic' crystal of HfO2 would likely exhibit ferroelectricity. Funakubo's team wanted to pinpoint the material's spontaneous polarization and the Curie temperature (the point above which a material stops being ferroelectric due crystal re-structuring). To do this, they needed to grow a carefully-ordered crystal on a substrate, a process known as epitaxy, which would give them well-defined data on an atomic scale.

The researchers found that one particular epitaxial film, labelled YHO-7, exhibited ferroelectricity with a spontaneous polarization of 45μC/cm and a Curie temperature of 450 °C (see image). The experimental results confirm earlier predictions using first principle calculations.

From a scientific and industrial point of view, a Curie temperature of 450 °C is of great interest, because it means the material could fulfil functions for future technologies. In contrast to many existing ferroelectric materials, the new thin-film exhibits compatibility with Si-based CMOS and is robust in miniature forms.

Background

Ferroelectric materials

Ferroelectric materials differ from other materials because their polarization can be reversed by an external electric field being applied in the opposite direction to the existing polarization. This property stems from the materials' specific crystal structure. Ferroelectric materials are highly valuable for next-generation electronics. While a number of ferroelectric materials are known to science and are already used in different applications, their crystal structure does not allow them to be scaled down to a small enough, ultra-thin film for use in miniaturized devices.

The material used by Funakubo and co-workers, hafnium oxide (HfO2), had previously been predicted to exhibit ferroelectric properties through first principle calculations. However, no research team had confirmed and examined these predictions through experiments. Funakubo's team decided to measure the properties of the material when it was deposited in thin-film crystal form onto a substrate. The precise nature of the crystal structure enabled the researchers to pinpoint the material's properties in full for the first time.

Their discovery of a particular epitaxial thin-film crystal of HfO2 that exhibits ferroelectricity below 450 °C will be of great significance in the field.

Implications of the current study

Funakubo's team are hopeful that their new thin film ferroelectric material will have applications in novel random-access memory and transistors, along with quantum computing. Their material is also the first ferroelectric material compatible with silicon-based semiconductors (Si-based CMOS).

Media Contact

Emiko Kawaguchi
media@jim.titech.ac.jp
81-357-342-975

http://www.titech.ac.jp/english/index.html

Emiko Kawaguchi | EurekAlert!

More articles from Materials Sciences:

nachricht Serendipity uncovers borophene's potential
23.02.2017 | Northwestern University

nachricht Switched-on DNA
20.02.2017 | Arizona State University

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Stingless bees have their nests protected by soldiers

24.02.2017 | Life Sciences

New risk factors for anxiety disorders

24.02.2017 | Life Sciences

MWC 2017: 5G Capital Berlin

24.02.2017 | Trade Fair News

VideoLinks
B2B-VideoLinks
More VideoLinks >>>