PREPARATION METHOD OF GAN SINGLE CRYSTAL BY MELTING

摘要

PURPOSE: A method for preparing GaN single crystal by melting is provided, to reduce defects such as dislocation due to the lattice mismatch and the difference of thermal expansion coefficients. CONSTITUTION: The method comprises the steps of mixing gallium(Ga) with Na or NaN3 being a catalyst in a furnace placed in an isolated reactor; flowing nitrogen gas into the reactor to increase the pressure and to make the nitrogen atmosphere; and heating the furnace to melt Ga and the catalyst and to grow GaN single crystal. Preferably the mixture of Ga and a catalyst contains further GaN single crystal with the size of 0.3-1.0 mm as a seed; and the mixture is doped with Mg, Na, Sr or Ba. The furnace is formed by using graphite, polycrystalline boron nitride.