3. Growth

3.1 General

Once the germ has exceeded the critical size, it starts to grow, and will continue to do so for as long as the medium remains supersaturated. Except in exceptional cases, the crystal is always bounded by flat F faces, with rough staircase S or notched K faces (figure ) disappearing very quickly, due to their excessive growth rate. We therefore consider here only the theories developed for F faces, which grow by lateral extension of layers, either by a two-dimensional sprouting growth mechanism (Fa face), or by a dislocation growth mechanism with development of a growth spiral (Fb face). The former applies to perfect crystals, the latter to crystals with dislocations....