A method comprises providing a structure defined by a silicon material on a buried oxide layer of a substrate; causing a nucleation of a III-V material in a sidewall of the structure defined by the silicon material; adjusting a growth condition to facilitate a first growth rate of the III-V material in directions along a surface of the sidewall and a second growth rate of the III-V material in a direction laterally from the surface of the sidewall, wherein the second growth rate is less than the first growth rate; and processing the silicon material and the III-V material to form a fin.