Our research encompasses thin film deposition and etching for applications in nanoelectronics, with a focus on selective processing for bottom-up fabrication of materials. Using the atomic layer deposition (ALD) and atomic layer etching (ALE) techniques as a starting point, novel approaches are developed to synthesize materials with atomic-level control.

Selective atomic-scale processing for fabrication of nanoelectronics

It is a long held dream in nanoscience to synthesize materials from the bottom-up with atomic-level control of structure and properties, yet the fabrication of nanoelectronics still relies almost completely on top-down processing. From a technological point-of-view, the motivation for working on bottom-up fabrication is that conventional top-down processing relying on photolithography and etching is reaching its limits in terms of alignment accuracy. Our research focuses on the development of new approaches for area-selective ALD based detailed insights from plasma physics and surface chemistry. Area-selective ALD aims at deposition of material only on surfaces where it is needed, without coating other surfaces of different materials, and thereby enables self-aligned fabrication. In addition, we are exploring other flavors of selective processing such as topographically-selective deposition or atomic-scale cleaning.

The downscaling of nanoelectronics to sub-5 nm dimensions also motivates current efforts in the field of ALE.   Earlier work in ALE primarily focused on anisotropic etching using plasma technology, but recent work also includes isotropic etching using thermal ALE processes. Our focus is on the unexplored option of plasma-based isotropic ALE, which broadens the range of materials that can be etched isotropically and enables ALE at low substrate temperatures.  Furthermore, we are working on improving anisotropic ALE processes by making use of ions with a well-defined energy.

Our research is inspired by in-depth understanding of the underlying mechanisms of deposition and etching. A crucial element of our research approach is the study of the reaction mechanisms of ALD and ALE processes using various in-situ techniques. The research comprises application-oriented projects in strong collaboration with industrial partners, as well as fundamental studies of the underlying mechanisms.