title: Self-Assembly of Islands on Spherical Substrates by Surface Instability.
abstract: Through strain-induced morphological instability, protruding patterns of roughly commensurate nanostructures are self-assembled on the surface of spherical core/shell systems. A three-dimensional (3D) phase field model is established for a closed substrate. We investigate both numerically and analytically the kinetics of the morphological evolution, from grooves to separated islands, which are sensitive to substrate curvature, misfit strain, and modulus ratio between the core and shell. The faster growth rate of surface undulation is associated with the core/shell system of a harder substrate, larger radius, or misfit strain. On the basis of a Ag core/SiO2shell system, the self-assemblies of SiO2nanoislands were explored experimentally. The numerical and experimental studies herein could guide the fabrication of ordered quantum structures via surface instability on closed and curved substrates.
authors.forename: Xiangbiao
authors.identifier: 0000-0001-8214-454X
authors.initials: X
authors.lastname: Liao
authors.forename: Junfeng
authors.initials: J
authors.lastname: Xiao
authors.affiliation: CAS Key Laboratory of Mechanical Behavior and Design of Materials, University of Science and Technology of China , Hefei 230026, China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Ni
authors.affiliation: Center for Optoelectronics Materials and Devices, Department of Physics, Zhejiang Sci-Tech University , Hangzhou 310018, China.
authors.forename: Chaorong
authors.initials: C
authors.lastname: Li
authors.affiliation: School of Chemical Engineering, Northwest University , Xi'an 710069, China.
authors.forename: Xi
authors.initials: X
authors.lastname: Chen
keywords: closed and curved substrates; misfit strain; ordered quantum structures; surface instability