Size dependent Young’s modulus of semiconductor nanowires: A theoretical approach

The present paper reports the Young’s modulus of semiconductor (viz. ZnO and TiO2) nanowires as a function of diameters considering both equilibrium strain and surface stress effect. A good agreement between the present calculated and available theoretical size dependent Young's modulus is found. The variation of relaxed/unrelaxed bulk materials surface and its effect on the Young’s modulus of the semiconductor nanowire is also demonstrated. A tensile (positive) surface stress can lead to an increase in the Young’s modulus and the decrease can be a result of a compressive (negative) surface stress. The surface stress plays an important role in determining the mechanical properties of the semiconductor nanowires.