Papers
Microstructural observation of β-gallium oxide nanostructures after ammonolysis
2015 年 123 巻 1440 号 p. 662-666
詳細
2015 年 123 巻 1440 号 p. 662-666
The reaction mechanism of β-gallium oxide (β-Ga2O3) to gallium nitride (GaN) under flowing ammonia was examined by observing the change in morphology according to the conversion of nanostructured β-Ga2O3 to GaN by ammonolysis. The morphology of the β-Ga2O3 nanostructures after ammonolysis was dependent on the experimental conditions (i.e. oxygen-rich and -deficient gas flow) for their growth. The surface of the β-Ga2O3 nanostructures grown in the oxygen-rich gas flow was striated after ammonolysis. On the other hand, the morphology of the β-Ga2O3 nanostructures grown in the oxygen-deficient gas flow was changed remarkably and diversely with maintaining their contour. These microstructural observations can be explained by the reaction mechanism, in which the ammonolysis of β-Ga2O3 to GaN consists of two successive reactions, the reduction of β-Ga2O3 to gaseous Ga2O and the nitridation of Ga2O(g) to GaN. The relative rates of the two reactions affect the morphology of the nitridated β-Ga2O3 nanostructures.
