The mechanical property and fracture behavior of GaN nanowire with pre-cut void under tension: a molecular dynamics study

Abstract A thorough understanding of the mechanical properties of GaN is a prerequisite for its application as a third-generation semiconductor. Here, we have investigated the mechanical properties of [001], [110] and [111] oriented GaN nanowires with pre-cut voids under uniaxial tension by using molecular dynamics simulation. The results indicate that the Young’s modulus, maximum stress and fracture strain strongly depend on the orientation of the GaN nanowire. As the fraction of void increases, the Young’s modulus changes little in [001] and [111] oriented nanowires but decreases notably in [110] oriented nanowire, while both maximum stress and fracture strain decrease prominently. Further investigations illustrate that the GaN nanowire with pre-cut void is firstly separated at the initial void, and then ruptures due to the spread of the void. Additionally, with the increasing temperature, the Young’s modulus decreases slightly regardless of the existence of pre-cut void, the maximum stress and fracture strain decrease notably in nanowire without void but change little in [001] oriented nanowire with pre-cut void. Our findings provide a deeper understanding of the mechanical properties of GaN nanowire, which paves the way for the applications in the microelectronic and photoelectric devices.