Fig. 1
Effect of electron beam (e-beam) irradiation on the crack behavior of Cu thin films during tensile loading. a Schematic diagram of e-beam irradiation and subsequent tensile testing. SEM images of Cu thin films deposited on polyimide (PI) substrates were captured at various levels of tensile strain, 0, 10, 20, and 30% (b) without irradiation and (c) with irradiation on the entire Cu film. The e-beam irradiation effectively suppresses the crack formation in the irradiated region even at a high tensile strain. SEM images of the Cu thin films irradiated only in specific region(s) such as (d) the upper half region, (e) the left half region, and (f) in ‘S’-shaped and ‘T’-shaped regions are shown. The local e-beam irradiation selectively prevents the crack formation in the Cu thin films on PI substrates. Scale bars, 10 μm (b–e); 100 μm (f)
