Natural variability in the surface roughness of combinatorial libraries of materials

Using a conventional method for the fabrication of solid-state combinatorial libraries, we have produced the binary libraries Fe1-xCrx and Mo1-xSnx(0 < x < 1) and found that their surface roughness is highly dependent on chemical composition. Roughness enhancements of up to 20-fold have been observed on the nanometer scale and were manifested in the boundaries between structurally dissimilar phases. It is anticipated that this is a common occurrence in thin-film libraries of metals and an obstacle in separating the influence of roughness and composition on the performance of library materials in biontaterial studies. (c) 2007 Elsevier B.V. All rights reserved.