By Kim Tae-gyu
Staff Reporter


A team of South Korean scientists has developed a new technology to bring conductivity to insulating materials and says it will lead to the development of 5-nanometer semiconductors, a milestone improvement from the current level of 60 nanometers.

``Many scientists believed that non-conducting metals, called Mott insulators, abruptly change to conductors with high-voltage shock but they failed to prove the hypothesis over the past 56 years, but we did it,’’ said team leader Kim Hyun-tak of the Electronics and Telecommunications Research Institute (ETRI).

In 1949, British scientist Nevill Mott was the first to explain this mysterious insulating behavior of some solid matters. This phenomenon was named after him.

Mott predicted the metal-insulator transition is caused by the repulsive interactions among electrons. Electricity passes through metals thanks to free-moving electrons.

Yet, electrons of Mott metals cannot move because of repulsive powers, thus making them unable to carry electricity. Mott foretold the states would collapse as soon as breaking the repulsive balance among electrons.

``We proved his prediction was 100 percent right with 10-plus year research and now have a technology to convert some metals to insulator and vice versa. We opened an era to control the electric characters of metals,’’ Kim claimed.

He foretold the new technology will have wide-ranging applications, saying, ``The 20th century was an age of semiconductors and this century will be an epoch of Mott insulators. These materials will open up the market of over $100 billion in the future.’’

For one instance, Kim said the technological stagnation in making semiconductors with circuits slimmer than 60 nanometers will be solved by deploying Mott insulators.

A nanometer is 1 billionth of a meter and companies try to make the semiconductor circuit slimmer because more thin circuit guarantees increased storage capacity in the memory chip.

Samsung Electronics, the world’s top memory chipmaker, stunned the world last year by unveiling the most advanced flash memory chips based on 60-nanometer-thick circuits but experts point out the thickness is almost a limit with current semiconductor resources of silicon.

``Silicon generates heat that cannot adopt ultra-slim circuits. But Mott metals do not generate heat while carrying out the same job of semiconductors. We expect the development of 5-nanometer items would be possible with Mott metals that exist abundantly in the nature and they would eventually replace semiconductors,’’ ETRI president Lim Joo-hwan said.

Foreign scientists heaped heavy praises on the landmark findings.

``Mott transition remained a major mystery for the science community for the last 50 years. New results obtained by Kim significantly advance our understanding of complex effects occurring in a prototypical system,’’ said professor Dimitri Basov at University of California.

Yasumoto Tanaka from Japan’s Institute of Advanced Science and Technology said: ``Korea has one of the greatest candidate, who will be able to get the Nobel Prize of Physics, maybe the first Nobel scientist of the country.’’

Kim’s team had applied for international and local patents for their technologies, which were featured on the New Journal of Physics last year and on the Applied Physics Letter earlier this year.

voc200@koreatimes.co.kr