In a laboratory in Vienna, a team of researchers has just saved the semiconductor industry billions of dollars — without having built a single new chip. Professor Mahdi Pourfath and Professor Tibor Grasser at TU Wien have uncovered a fundamental problem with promising next-generation materials that could have derailed years of development work and billions in investment. Their findings, published in Science, point not to a dead end, but to a clear path forward.
For years, engineers have raced to shrink computer chips smaller than ever before, pushing the limits of what silicon can achieve. The frontier lies in two-dimensional materials — ultrathin layers just one or a few atoms thick, such as graphene or molybdenum disulfide. These materials boast extraordinary electronic properties that could enable faster, more compact devices. But Pourfath and Grasser have shown that something crucial has been overlooked: what happens when these atomically thin semiconductors meet their insulating partners.
The issue lies in a nanoscale gap that inevitably forms between the semiconductor and the insulator layer. In many material combinations, the two layers are held together only by weak van der Waals forces — they never truly touch. This gap measures a mere 0.14 nanometers, thinner than a single sulfur atom, yet it fundamentally limits how small these devices can become. To put that in perspective, a SARS-CoV-2 virus is roughly 700 times larger than this invisible barrier. Even the most promising 2D materials, with perfect intrinsic properties, cannot overcome this obstacle as long as the gap exists.
The researchers call the solution "zipper materials" — combinations where the semiconductor and insulator interlock rather than merely resting against each other. Unlike the loosely connected pairs, these materials form a stronger bond that eliminates the problematic gap entirely. The insight came from refusing to study 2D materials in isolation. "A 2D material alone does not make an electronic device," said Pourfath. "We also need an insulating layer — and this is where things become more complicated."
The implications are significant. Without this research, the industry risked pouring resources into approaches constrained by basic physics. "We can predict which materials are suitable for future miniaturization steps — and which are not," said Grasser. Their work transforms what could have been a costly detour into a roadmap, identifying from the outset which material combinations deserve investment and which should be set aside. For a global semiconductor industry constantly seeking the next breakthrough, knowing what won't work can be just as valuable as discovering what will.