In Situ Study of Growth Dynamics in Au-Seeded GaSb Nanowires

Abstract

Understanding the growth dynamics of III-V nanowires is crucial to attaining the atomistic control of nanowire growth required for the fabrication of high-quality devices.In situ studies allow us to monitor the individual processes of the cyclic layer-by-layer growth, which permits us to gain more insight into the growth dynamics than using conventional growth studies. Here, we demonstrate how the incubation and step-flow process times that govern nucleation and layer propagation depend on the nanoparticle composition and growth conditions in steady-state growth of Au-seeded GaSb nanowires. We find that both processes are predominantly affected by the number of Sb atoms dissolved in the nanoparticle, which is further influenced by the exchange rate of Sb atoms across the liquid−vapor interface. Additionally, we find that the growth dynamics are further complicated due to the interrelated nature of Ga and Sb atoms in the liquid phase. Lastly, we show that the complex growth behavior observed experimentally can be explained by conducting Monte Carlo-based nanowire growth simulations that accurately reproduce the observed trends. The results presented in this study demonstrate that a comprehensive understanding of nanowire growth can be achieved with careful consideration of all phases and growth species.