Applications of molecular dynamics simulations to crystal growth: Step energies and low temperature growth

Molecular dynamics simulations with realistic atomic potentials provide a useful model for testing concepts important for crystal growth, To illustrate this, we discuss two problems in Si/Ge(100) systems: the behavior of step energies under bulk strain, and the effect of low-energy atomic beams on growth at low temperatures. Recent experiments show that in Si/Ge(100) systems, strain induced roughening depends sensitively upon the sign of the strain: the system roughens under compression, but remains relatively smooth under tension. Molecular dynamics simulations show that this behavior may be correlated with the behavior of the Si(100) steps under bulk strain, Concerning low temperature growth, we show that the crossover temperature for the amorphous to crystalline transition may be depressed significantly through the use of low-energy atomic beams.