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We examine the detailed structure of ion-assisted physical vapor deposited coatings applied to sharp edges, with particular emphasis on the region at the tip of the edge. The problem is studied on the example of a 30° wedge coated with TiAlN/VN deposited by unbalanced magnetron sputtering at a substrate bias -75 V. Cross-sectional TEM analysis shows that the grain structure of the coating on top of the wedge is different than in the case of a flat surface. Simulations of the ion transport across the plasma sheath and of the ion impact at the surface describe the characteristics of the ion bombardment at the edge. In the vicinity of the edge, the ions enter at very steep angles of incidence, which increases the energy deposited into the growing layer and thus promotes the growth of larger crystallites. An exception is the region right at the very tip of the edge where, due to the nonzero radius of curvature, the incidence of the ions at the growth surface is perpendicular—this region is shown to have a different microstructure. Additional changes in the internal structure are due to the curvature of the coating at the tip of the edge. © 2004 American Vacuum Society.