Fabrication of m-axial InGaN nanocolumn arrays on silicon substrates using triethylgallium precursor chemical vapor deposition approach

We demonstrated the catalytic growth of m-axial InxGa1−xN (0.10 ≤ x ≤ 0.17) nanocolumn arrays with high crystallinity on silicon substrates using metal-organic chemical vapor deposition with trimethylindium (TMIn), triethylgallium (TEGa), and ammonia as precursors. The high quality of InGaN nanocolumns (NCs) were believed to be due to the utilization of TEGa that achieved less carbon impurities and offered more comparable vapor pressure with that of TMIn at low temperature. In addition, these NCs were grown in non-polar m-axis, which the internal electric field of the InGaN that often deteriorates the device performances might be able to be eliminated. Furthermore, the bandgap of this InGaN can be modulated from UV to visible region simply by tuning the ratio of the precursor during the fabrication. Our results suggest an approach to the fabrication of large-area NCs with a tunable bandgap on a silicon substrate by the standard MOCVD method that offers an immense opportunity for electronic and photonic applications and allows the scale-up from a research laboratory to industrial scale.