Cardiff University researchers have, for the first time, noticed previously unobserved “instabilities” on the surface of a common compound semiconductor material.
The findings could probably have substantial adverse effects on the development of future materials in the electronic devices that energy our daily lives.
Compound semiconductors are an integral part of digital gadgets, from smartphones and GPS to satellites and laptops.
The new findings, published in the leading journal Physical Review Letters on November 1, 2019, have revealed how the surface of a frequently used compound semiconductor material — gallium arsenide (GaAs) — isn’t as stable as previously considered.
Using state-of-the-art equipment at Cardiff University’s School of Physics and Astronomy and the Institute for Compound Semiconductors, the team has identified small pockets of instability in the atomic structure of GaAs that tend to come on surface and then disappear.
It’s the first time that this phenomenon, called “metastability,” has been noticed on GaAs surfaces.
Co-writer of the study Dr. Juan Pereiro Viterbo, from Cardiff University’s School of Physics and Astronomy, stated: “At the moment we have no idea whether or not this phenomenon is affecting the progress of semiconductor device structures — that is what we have to study next.
The key to this discovery was the availability of equipment with capabilities that don’t exist anywhere else on the planet.
The labs on the School of Physics and Astronomy and the Institute for Compound Semiconductors have a low energy electron microscope mixed with a molecular beam epitaxy machine that allows researchers to look at dynamic modifications on the structure of materials while compound semiconductors are being built.