Effect of Substrate Orientation and Catalyst Droplet Size on the Growth Direction of Silicon Nanowires

The growth of silicon nanowires is simulated by the Monte Carlo method using the vapor–liquid–solid method (VLS) with gold droplets as a catalyst. The growth of tilted nanowires on Si surfaces with (111), (011), and (100) orientations is considered. It is found that the size of gold droplets affects the orientation and morphology of silicon nanowires. The growth of tilted nanowires using small droplets in the $$\langle 011\rangle$$ and $$\langle 211\rangle$$ directions is demonstrated. As the droplet size increases, the most probable direction of nanowire growth becomes $$\langle 111\rangle$$ . Diagrams demonstrating the probability of the growth direction of nanowires on Si surfaces with different orientations depending on the gold droplet size are presented. The kinetics of unstable growth of silicon nanowires catalyzed by small droplets is analyzed.