Atomic scale modeling of vicinal surface growth from melts using the phase-field crystal method

• We simulate the bcc {1 1 0} vicinal surface growth from melt at the atomic scale by using phase field crystal method.
• We investigate the influence of terrace width, step direction and supersaturation on step flow growth kinetics.
• For island growth on terrace, the growth exponent of each layer in multi-layer island is investigated.
• We obtain the growth mechanism selection map with respect to terrace width and supersaturation.

Using the phase-field crystal method, we investigated the bcc {1 1 0} vicinal surface growth from melts at the atomic scale with emphasis on the growth kinetics of two growth modes: step flow growth and island growth on terrace. Simulation results show that, for step flow growth, with the decrease of terrace width, the competition for feeding atoms between neighboring steps causes growth rate vs. step density to deviate from a linear relationship, and finally converge to a finite value. The step crystal direction also strongly influences the growth kinetics: vicinal surface with steps along the closest packed direction—[1 1 1] grows slower than that with [0 0 1] step. For island growth on terrace, the growth exponent of each layer in multi-layer island gradually transits from 1/2 for the top layer to 1/3 for the bottom layer, which demonstrates the transition from global diffusion controlled growth for top layer to surface diffusion controlled growth for bottom layer. The growth mechanism selection map with respect to terrace width and supersaturation is summarized and atom attaching rates of different growth mechanisms are also compared.