Study of Si(100) surface step convergence kinetics

In this work, the convergence kinetics investigations of the S$_{\mathrm{A}}$- and S$_{\mathrm{B}}$-steps on Si(100) substrates with inclination 0.5$^\circ$ and 0.1$^\circ$ were carried out. Analysis of the time dependence of reflection high-energy electron diffraction (RHEED) intensity was used to establish the growth kinetics character on vicinal Si(100) surfaces. It is shown that, in a Si flow at the growth rate of 0.37 ML/s, the step convergence velocity has a decreasing exponential dependence with the temperature increase. It is determined that the single-domain surface formation velocity increases with an increase in the terrace width on the surface, which may be due to the partial participation of growth due to the formation of two-dimensional islands. Above a temperature of 650$^\circ$C, the dominant growth mode is due to the step movement and the single-domain surface formation velocity decreases with an increase in the terrace width. Thus, the single-layer step convergence is determined by both the MBE growth conditions and the Si(100) substrate orientation. The convergence of S$_{\mathrm{A}}$- and S$_{\mathrm{B}}$-steps of the Si(100) surface is explained by the slowdown of the step S$_{\mathrm{A}}$-motion, which is associated with complex permeability mechanisms and a kink formation of steps. It is assumed that the reason for the slowdown of the step convergence with increasing temperature is an increase in the kink density at the S$_{\mathrm{A}}$-step, which reduces the step S$_{\mathrm{A}}$-permeability coefficient.