We have deposited thin metal films that include a granular indium layer on polymer substrates and observed the resistance of the film changed by a factor of less than 2, even as the sample is uniaxially stretched to the point of rupture ͑ϳ38% strain͒. The presence of a discontinuous layer of indium islands in these films maintains the electrical conductivity by providing a bridging mechanism across the cracks formed in the underlying continuous film layers. A simple model is used to relate the applied strain to the electrical resistance of the metal films. Furthermore, we present the data for these films under cyclic loading around a cylindrical mandrel which show that there is no change in resistance under these fatigue testing conditions for 10 000 loading cycles.

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We report on a robust metallization scheme ideal for interconnects required in flexible display applications. Multi‐layered metal interconnects including a granular discontinuous ductile indium layer, have been deposited on a variety of compliant substrates to confirm that there is a minimal change in resistance even when subjected to large mechanical strains and repeated low‐strain fatigue loading. Initial analysis of deformed films also suggests there is a possibility for a self‐healing process. A finite element analysis (FEA) model of the thin‐metal film/polymer substrate structure, also confirms the stretchability of the granular indium islands observed to be bridging the cracked regions in the underlying conductive layers.