New in Acta Materialia: quantifying competitive grain overgrowth

It is half a century since van der Drift published on the principle of competitive grain overgrowth in polycrystalline thin films. In this new article published in Acta Materialia, we measure and compare the grain size evolution of a-textured polycrystalline ZnO thin films grown under three different conditions, using TEM-based automated crystal orientation mapping combined with a “double wedge” sample geometry. For the first time, we present experimental data which quantitatively confirm the power-law behavior and exponent that are analytically predicted for the van der Drift model in 3-D. By careful analysis of the data, and by comparing to appropriate simulations, it is further shown how this result is contingent on the absence of factors such as textured nucleation and renucleation during film growth, as is the case for one of the three films.