The role of abnormal grain growth on solid-state dewetting kinetics

Galit Atiya (1) , Dominique Chatain (2) , Vissarion Mikhelashvili (1) , Gadi Eisenstein (1) , Wayne D Kaplan (1)

1 Technion - Israel Institute of Technology [Haifa]
2 CINaM - Centre Interdisciplinaire de Nanoscience de Marseille

Continuous thin films of Pt on A-plane 1 1 2 0 À Á sapphire substrates were dewetted to characterize the morphological evolution and dew-etting kinetics at 800 °C using an oxygen partial pressure of 10 À20 atm. Hole growth was studied, focusing on partially dewetted samples. Four different low-index orientation relationships were found between the Pt and sapphire substrate by electron backscattered diffraction combined with transmission electron diffraction patterns. Abnormal grains adjacent to the holes with a small deviation from one of the low-index orientation relationships were observed. The difference in the heights of the abnormal grains adjacent to the holes (rim-height) is influenced by the initial position of the hole, and the existence of grains with a low-energy interface orientation relationship, and not only by diffusivity rates dictated by surface orientation as described in existing edge-retraction models. The existence of low-index orientation relationships is seen as the driving force for abnormal grain growth in the vicinity of the holes, and is a dominant factor in controlling the dewetting rate of thin metal films on oxide surfaces.

Keywords: Abnormal grain growth; Interfaces; Crystallographic orientation; EBSD; Solid-state dewetting

Domains: Chemical Sciences; Material chemistry; Physics [physics]; Condensed Matter [cond-mat]; Materials Science [cond-mat.mtrl-sci]

Galit Atiya, Dominique Chatain, Vissarion Mikhelashvili, Gadi Eisenstein, Wayne D Kaplan. The role of abnormal grain growth on solid-state dewetting kinetics. Acta Materialia, 2014, 81, pp.304 - 314. ⟨10.1016/j.actamat.2014.08.038⟩. ⟨hal-01722656⟩