Island Shape Transition in Heteroepitaxial Metal Growth on Square Lattices
نویسندگان
چکیده
A novel mechanism for ramified island growth in the initial stages of metal heteroepitaxy is reported. Scanning tunneling microscopy measurements reveal that copper islands on Ni(100), as they grow in size, undergo a shape transition. Below a critical size of ø480 atoms, compact islands form, while above this size they develop a ramified shape. This effect is not of kinetic origin and has been observed in an extended range of growth temperature (250–370 K) and deposition flux s1025 1022 monolayerysd. The shape transition is ascribed to the island size dependent strain relaxation. [S0031-9007(98)05561-6]
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