In-assisted growth of InN nanocolumn on Si(111) substrate by molecular beam epitaxy

• Well-aligned InN nanocolumns were deposited on Si(111) substrate by plasma-assisted MBE using vapor–liquid–solid method.
• The catalyst thickness has a critical influence on the morphology and crystal quality of InN nanocolumns.
• The quality of InN layers presented significant improvements with the proper V/III radio.

We have demonstrated that the thickness of the catalyst layer plays a significant role in the morphology and the material quality of the InN nanocolumns grown on Si(111) substrate by plasma-assisted molecular beam expitaxy using vapor-liquid-solid method. A systematic investigation of In catalyst films was undertaken, revealing that high density uniform InN can not be obtained when the In catalyst is either too thin or too thick and the appropriate thickness of the deposited In was 1 nm. The influence of V/III radio on the growth procedure is also discussed, and as proved, a higher V/III radio is necessary to be used to get high density nanocolumns and improved optical property.