Beyond the Silicon Age

New, energy efficient materials that can replace silicon are necessary to support the future growth of micro-electronics. Not only are the limits of Moore's Law in sight, but our digital ecosystem is increasingly using more electricity. So says Nicola Spaldin, Professor of Materials Theory from the ETH Zürich.

Spaldin does fundamental research into materials and developed a new type: multiferroic materials. These possess both ferroelectric as well as ferromagnetic properties. In Nature there are materials that have one or the other characteristic but a combination of both does not occur. But there is no law in Nature that precludes this combination, as Spaldin discovered. And therefore she created, together with her team, the new multiferroic materials. Meanwhile much research is going into this, but Spaldin is recognized as the founder of this research area.

The Silicon Age
In a recent, beautifully written paper, Spaldin explains succinctly how the application of new materials gave direction to human civilization. So much so, that we name our historical ages after them. In the Bronze Age, for example, the newly acquired knowledge of working with metals went together with the emergence of cities, trades and commerce.

‘So now we live in the “Silicon Age”, with silicon transistors forming the core of much of the microelectronics that enable our modern way of life', writes Spaldin. ‘Since those very first transistors in the 1940s and 50s, we have improved the properties of silicon devices to an astonishing extent, enabling the transformation for example from clunky old main-frame computers to sleek smartphones with tremendous capabilities, all with the same material: silicon'.

Glutton
This enormous amount of progress is thanks to Moore's Law: the prediction from 1965 that the number of transistors in an integrated circuit will double every two years. ‘But this silicon revolution will soon be forced to come to an end as we start to run into fundamental physical limits', writes Spaldin. ‘Limits are set by the size of the individual atoms that make up the silicon material.'

Furthermore, the forever expanding IT infrastructure slurps increasing amounts of power. Partly because of the rise of the Internet of Things and the fact that an increasingly larger part of the world population gains access to the internet. If the current growth trend continues and IT devices do not become more energy efficient, then the increasing power consumption will become unbearable in a few decades.

Radical change
New materials are required to continue to support the exponential growth of micro-electronics that we have become accustomed to and to develop more energy efficient devices. And that requires fundamental research, says Spaldin. Applied science generates faster and easier to measure results. But fundamental science can open the door to completely new possibilities.

This was the case for Spaldin. Once she and her colleagues had created the new material, it turned out to have unexpected properties. Spaldin: 'we demonstrated that we are able to modify the magnetic properties of multiferroics with electric fields. This is exciting from a basic physics perspective: usually a magnetic field is needed to modify magnetic properties. But it also has profound technological implications: Replacing the magnetic fields in our existing magnetism-based technologies with electric fields offers tremendous opportunity for energy savings, miniaturization and efficiency.'

Now that the Silicon Age is starting to run into its limits, it is becoming high time for a new material. Perhaps these are multiferric materials and perhaps something else, says Spaldin. But in any case, the funding for fundamental research is necessary to pave the way to the next Age.

Nicola Spaldin's article Fundamental Materials Research and the Course of Human Civilization is freely available from arxiv.org.

Image: Banksy street art. Photo by: Salvatore Vastano. CC BY-ND 2.0 license.

Via: Technology Review