Abstract
GaN single crystals with a size of 0.2-2.0 mm were prepared in a stainless-steel tube at 600 to 800℃ from Ga using a Na flux and N_2 from the thermal decomposition of sodium azide, NaN_3. The morphology of the single crystals grown in a Na flux was prismatic or platelet. The crystals were characterized by Auger electron spectroscopy (AES), energy dispersive X-ray spectroscopy (EDX) and cathodoluminescence spectroscopy. Hall measurements were carried out for platelet single crystals with a size of 0.4-0.7 mm. The polarity was determined by X-ray diffraction using X-ray anomalous dispersion.
