Understanding of the crystal growth mechanism
The recent understanding of the crystal growth mechanism is reviewed. The transport of growing atoms and molecules through a bulk solution and a vapor phase to a growing surface is discussed and it is noted that the surface supersaturation is the key factor for the growth. Growth velocity is obtained as a function of the surface supersaturation when steps are supplied from two-dimensional nuclei or dislocations with a screw component. Akasaka et al. conducted the growth of GaN by Metal Organic Vapor Phase Epitaxy (MOVPE) and obtained the growth rate as a function of surface supersaturation, which was determined by the spiral step distance. It was found that the BCF theory agrees with the experimental results very well. The mechanism of intersurface diffusion is also discussed.
- 1 Professor Emeritus, The University of Tokyo
- 2 Toyohashi University of Technology