Electropolishing—A Practical Method for Accessing Voids in Metal Films for Analyses

In many applications, voids in metals are observed as early degradation features caused by fatigue. this publication, electropolishing is presented the context of a novel sample preparation method that capable accessing interior metal thin films along their lateral direction material removal. When performed at optimized process parameters, removal can be well controlled and surface becomes smooth micro scale, resulting being distinguishable from background scanning electron microscopy images. Compared to conventional cross-sectional (embedded mechanical cross-section or focused ion beam), accessed not constrained thickness investigated film laterally resolved void analyses possible. For demonstrational purposes method, distribution metallization thermo-mechanically stressed microelectronic chips has been quantified.