New lab for building materials at the atomic scale

At the recently inaugurated WISE Atomfab at Albanova, researchers can produce extremely thin films and control their composition and structure with very high precision. WISE Atomfab is part of Albanova Nanolab (ANL), and the latest addition to the infrastructure is equipment for advanced ALD (atomic layer deposition), a technique that allows researchers to build up materials layer by layer. The films can be just a few nanometres thick and, in some cases, even thinner.

The Nanolab has previously been able to produce thin films, but the new equipment also allows researchers to coat three-dimensional structures with material.

“This makes it possible to create new types of chips where thin films can be bent around corners. One example is optical waveguides, where so-called single-photon detectors can be placed on the side or around the structure,” says Erik Holmgren, one of the researchers at the lab.

Using ALD technology, the researchers can also deposit very thin layers of certain materials, particularly superconducting nitrides, using chemical methods.

“Chemical methods allow us to control new parameters, such as film stress, density and crystallinity. When we can control virtually every atomic layer, we can produce thinner and more homogeneous films than before. This is particularly interesting for quantum applications, where properties such as kinetic inductance are highly dependent on the thickness of the material. Ultra-thin films can also exhibit properties that are difficult to achieve, or are completely absent, in thicker films,” Erik Holmgren explains.

By controlling materials on this tiny scale, researchers can create properties that are difficult or impossible to achieve using conventional materials manufacturing.

The lab also houses equipment for CVD, or chemical vapour deposition. Using gases and plasma, among other things, researchers can create thin films with properties that are difficult to achieve using conventional manufacturing methods.

For the researchers at WISE Atomfab, quantum technology is another area of particular interest.

“We will use ALD for superconducting, semiconducting, and insulating materials to be used in quantum technology. When certain materials are made extremely thin, their properties can change in ways that are of interest for quantum devices and circuits.”

Open to researchers from outside KTH

Other areas that can benefit from this advanced technology include photonics, where components that manipulate light need to be manufactured, and materials for energy conversion, such as those used in solar cells. Other potential applications include pharmaceutical manufacturing and catalysts, as was highlighted in presentations by ANL researchers during the inauguration.

WISE Atomfab is fully open to researchers from outside KTH, within the national network of Myfab and the Nordic Nanolab Network. Colleagues come here from the Stockholm University and the Karolinska Institute, regional spinoffs and startups, as well as from industry at large, explains Adrian Iovan, who works at the lab.

“More people could certainly be made aware that this facility exists. I’m very proud of this lab. It’s small but efficient and is turning into something extremely good,” he says.

Representatives from WISE and KTH management attended the opening, including Professors Olle Eriksson, Lars Kloo, Anders Forsgren, Oscar Tjernberg and Carlota Canalias. Teachers and early-career researchers from Albanova Nanolab also presented their projects.

Vladislav Korenivski, professor and director of Albanova Nanolab, gave a tour of the new facility. His vision is for the lab to bring together the tools and processes needed for research and development at the nanoscale, while providing strong support for users and making efficient use of resources.

Text: Anna Gullers, KTH Royal Institute of Technology