Effect of internal stress on short-circuit diffusion in thin films and nanolaminates: application to Cu/W nano-multilayers

•In situ heating AES is performed on PVD-grown Cu/W nano-multilayers.•Nanoscale diffusion is assessed upon initial nano-multilayer degradation.•A GB diffusion model, including the stress evolution during annealing, is developed.•The stress-free activation energy of Cu GB diffusion in W is derived.•Compressive stress in W barriers increases the activation energy for Cu GB diffusion.