Modelling Grain Growth in Thin Films.

2023-05-11   Lecture by dr.rer.nat.habil. Dana Zöllner.

Abstract:
Thin films undergoing grain growth are not only interesting from a purely scientific perspective, but also important to understand from a technological point of view.
The grain size influences many mechanical and optical properties of a material and, hence, changes in the size as they occur during grain growth influence not only the microstructure itself but also materials’ properties. Especially when it comes to thin films it is not only the polycrystalline grain structure and the properties of the grain boundaries that have to be taken into consideration, but also the thickness of the film is rather important.
It has been observed that when the grain size reaches the magnitude of the layer thickness, the coarsening slows down and may even come to a full stop.

This lecture will show a three-dimensional Monte Carlo Potts model approach for grain growth in thin films under a broad variety of conditions. Even under ideal coarsening conditions (normal grain growth) the three-dimensional nature of the digital thin film yields important insights that cannot be obtained from simplified 2D considerations. However, the coarsening process gets more complicated when temperature gradients or surface effects such as grain boundary grooving are taken into account.