Fundamental breakthrough in the future of designing materials

July 27, 2017, Trinity College Dublin
Professor John Boland pictured at the Scanning Tunnelling Microscope. Credit: AMBER, Trinity College Dublin

A team of researchers from AMBER centre based in Trinity College Dublin, have made a breakthrough in the area of material design - one that challenges the commonly held view on how the fundamental building blocks of matter come together to form materials.

Professor John Boland, Principal Investigator in AMBER and Trinity's School of Chemistry, researcher Dr. Xiaopu Zhang, with Professors Adrian Sutton and David Srolovitz from Imperial College London and University of Pennsylvania, have shown that the granular in can never fit together perfectly, but are rotated causing an unexpected level of misalignment and surface roughness. This behaviour, which was previously undetected, applies to many beyond copper and will have important implications for how materials are used and designed in the future. The research was published today in the prestigious journal, Science. The Intel Corp. Components Research Group also collaborated on the publication.

Electrical, thermal and mechanical properties are controlled by how the grains in a material are connected to each other. Until now, it was thought that grains, which are made up of millions of atoms, simply pack together like blocks on a table top, with small gaps here and there. Professor Boland and his team have shown for the first time that nano-sized grains in copper actually tilt up and down to create ridges and valleys within the material. Nanocrystalline metals such as copper are widely used as electrical contacts and interconnects within integrated circuits. This new understanding at the nanoscale will impact how these materials are designed, ultimately enabling more efficient devices, by reducing resistance to current flow and increasing battery life in hand-held devices.

Professor John Boland, Principal Investigator in AMBER and Trinity's School of Chemistry, said, "Our research has demonstrated that it is impossible to form perfectly flat nanoscale films of copper and other metals. The boundary between the grains in these materials have always been assumed to be perpendicular to the surface. Our results show that in many instances these boundaries prefer to be at an angle, which forces the grains to rotate, resulting in unavoidable roughening. This surprising result relied on our use of scanning tunnelling microscopy which allowed us to measure for the first time the three-dimensional structure of grain boundaries, including the precise angles between adjacent ."

Professor John Boland from AMBER and Trinity College Dublin's School of Chemistry outlines his team's discovery that nano-sized grains in copper are not flat, but actually tilt up and down to create ridges and valleys within the material. Nanocrystalline metals such as copper are widely used as electrical contacts and interconnects within integrated circuits. This new understanding at the nanoscale will impact how these materials are designed, ultimately enabling more efficient devices, by reducing resistance to current flow and increasing battery life in hand-held devices. Credit: AMBER, Trinity College Dublin

He added, "More importantly, we now have a blueprint for what should happen in a wide range of materials and we are developing strategies to control the level of grain rotation. If successful we will have the capacity to manipulate material properties at an unprecedented level, impacting not only consumer electronics but other areas such as medical implants and diagnostics. This research places Ireland yet again at the forefront of material innovation and design."

Dr. Xiaopu Zhang and Professor John Boland. Credit: AMBER, Trinity College Dublin

Explore further: State of the art sensors made from graphene and children's toy silly putty

More information: Zhang X, Han J, Plombon JJ, Sutton AP, Srolovitz DJ, Boland JJ. Nanocrystalline copper films are never flat. Science 28 July 2017 science.sciencemag.org/cgi/doi … 1126/science.aan4797

Related Stories

Model simulates atomic processes in nanomaterials

March 1, 2007

Researchers from MIT, Georgia Institute of Technology and Ohio State University have developed a new computer modeling approach to study how materials behave under stress at the atomic level, offering insights that could ...

World's smallest shamrock created by scientists

March 17, 2014

AMBER, Ireland's national materials science centre based in Trinity College Dublin has etched a nano sized shamrock whose stem is approximately 200,000 times smaller than a grain of salt. The shamrock, 500 of which could ...

Recommended for you

Atomic-scale manufacturing now a reality

May 23, 2018

Scientists at the University of Alberta have applied a machine learning technique using artificial intelligence to perfect and automate atomic-scale manufacturing, something which has never been done before. The vastly greener, ...

1 comment

Adjust slider to filter visible comments by rank

Display comments: newest first

Sonhouse
not rated yet Jul 27, 2017
That begs the question if that roughness and misplaced angles can be fixed. I didn't see them talk about solutions, only identifying problems. At least that is a start.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.