Label-/tag-free traceability of electronic PCB in SMD assembly based on individual inherent surface patterns

Individual traceability of components enables efficient quality control, improving operational efficiency, or smart manufacturing approaches like big data analysis as well as customized mass production. Conventional track and trace solutions however, require a tag or label which is often not attachable due to e.g., spatial or economic reasons. A promising alternative is the identification of components based on individual, inherent surface patterns. For a set of 115 printed circuit boards, it is shown that fiducial markers, which are commonly used for alignment of components, can possess such individual surface patterns and hence serve as unique identifier. As the investigations are based on industrial conditions, the paper transfers the approach of label-/tag-free traceability from laboratory to an application in an industrial environment. Furthermore, faultless traceability of all samples within a SMD assembly line is achieved demonstrating the robustness of the identification against changes of the surface.