Study of growth mechanism of self-catalytic branched GaN nanowires

• To propose the formation path of self-inducing branched GaN nanowires.
• The spontaneous branch formation was based on self-catalytic VLS growth model.
• Accumulation of Ga-rich liquid was accounted for the outgrowth, as confirmed by EDS.

In this article, we report the investigation of GaN nanowires grown by chemical vapor deposition method with the use of Fe as catalyst. Branched nanowires were accidentally found during morphological examination on the grown samples using field emission scanning electron microscope (FESEM). Our study revealed that the spontaneous production of branched GaN nanowires was not attributed to the Fe catalyst. We propose that the inducement of branched GaN nanowires was based on self-catalytic vapor–liquid–solid (VLS) growth model, in which the high concentration of Ga liquid was found to be responsible for the growth of branched nanowires. This proposed growth model was confirmed by the collection of the elemental analysis measurement on various spots of the branched nanowires using energy dispersive X-ray spectroscopy (EDS).