Measuring the thickness of metal coatings: A review of the methods

Thickness dramatically affects the functionality of coatings. Accordingly, the techniques in use to determine the thickness are of utmost importance for coatings research and technology. In this review, we analyse some of the most appropriate methods for determining the thickness of metallic coatings. In doing so, we classify the techniques into two categories: (i) destructive and (ii) non-destructive. We report on the peculiarity and accuracy of each of these methods with a focus on the pros and cons. The manuscript also covers practical issues, such as the complexity of the procedure and the time required to obtain results. While the analysis focuses most on metal coatings, many methods are also applicable to films of other materials.