Effects of film thickness on critical crack tip opening displacement in single-crystalline and polycrystalline submicron Cu films. (July 2016)

• Record Type: Journal Article
• Authors: Hirakata, Hiroyuki; Yoshida, Takuya; Kondo, Toshiyuki; Minoshima, Kohji
• Is Part Of: Engineering fracture mechanics. Volume 159(2016)
• Page Start: 98
• Page End: 114
• Publication Date: 2016-07
• Subjects: Thin films -- Fracture toughness -- Crack tip opening displacement -- Size effects -- Single crystal -- Copper; Fracture mechanics -- Periodicals; Rupture, Mécanique de la -- Périodiques; Fracture mechanics; Periodicals; 620.112605
• DOI: 10.1016/j.engfracmech.2016.03.031
• Languages: English
• ISSNs: 0013-7944

Abstract

Abstract: We performed in - situ field emission scanning electron microscopy fracture toughness tests on single-crystalline and polycrystalline submicron-thick Cu films. In all specimens, the notch root became blunt, and a crack was initiated from the blunted notch root. The critical crack tip opening displacement (CTOD) for crack initiation, δ i, was thickness dependent, where δ i decreased with a decrease in the thickness. The critical CTOD normalized by the thickness, δ i / B, values of the films were similar ( δ i / B = 1.4–1.9), irrespective of the film thickness and microstructure. This suggested that the local fractures of the submicron Cu films were similar.