Study on electrical transport properties of strained Si nanowires by in situ transmission electron microscope

Strain engineering in semiconductor nanostructure has been received great attention because their ultra-large elastic limit can induce a broad tuning range of the physical properties. Here, we report how the electrical transport properties of the p-type ?100?-oriented Si nanowires may be tuned by bending strain and affected by the plastic deformation in a transmission electron microscope. These freestanding nanowires were prepared from commercial silicon-on-insulator materials using the focusing ion beam technique. Results show that the conductivity of these Si nanowires is improved remarkably by bending strain when the strain is lower than 2%, while the improvement is nearly saturated when the strain approaches to 2%. The electric current will reduce a little sometimes when strain exceeds 3%, which may result from plastic events. Our experimental results may be helpful to Si strain engineering.