Papers by Keyword: Growth Habit

Abstract: The plane surface energy of the mullite crystals (001), (010), (100) and (-100) is comparative calculated by using first-principles plane-wave pseudopotential method and the open hydrothermal system preparing mullite phase crystal test conditions. Also the plane growth habits can be predicted according to the results. The result shows that: the descending order of the mullite crystal surface energy is: E₍₀₀₁₎ > E₍₀₁₀₎ > E_(-100) > E₍₁₀₀₎. On the basis of Cune-Woolf principle, the surface energy of mullite crystals (001) surface is the maximum and growth rate is the fastest. Thus the (001) crystal face is growth surface habits of mullite phase crystal. Crystal growth morphology mostly extends in one direction.

Abstract: Seeded growth of gallium nitride (GaN) crystals on a spontaneously nucleated small GaN by the Na flux method was performed. In this study, we attempted to control the growth habit by changing the flux composition (Ga/Na) and by introducing a small amount of additives (Ca and Li). Our experiment clarified that a low Ga composition was preferred to grow high-crystallinity prismatic GaN crystals with a high growth rate. Furthermore, the transparent GaN single crystals with prism shape could be grown by the addition of Ca and Li.