Forward bending of silicon nanowires induced by strain distribution in asymmetric growth

The flexibility and quasi-one-dimensional nature of nanowires offer wide-ranging possibilities for novel heterostructure design and strain engineering. In this work, we realized controllably bent Si nanowires by using asymmetric growth with electron beam evaporation system. It is demonstrated that the degree of arc-bending depends on the deposition angle and deposition thickness. The forward bending of the Si nanowires is due to the lattice mismatch and thermal mismatch between Si and the metallic materials such as Cr and Ti, which can be generally utilized to control the shape and internal strain of Si nanowires, with potential applications for fabricating desired nano-devices.