InN/InAlN Multiple Quantum Well Nanocolumns Grown on (111) Si Substrates by RF-Plasma Assisted Molecular Beam Epitaxy

Abstract

High In content InxAl1-xN nanocolumns were successfully self- assembled on Si (111) substrates under nitrogen-rich conditions, by rf-plasma assisted molecular beam epitaxy. The InAlN nano-columns (XIn=0.87) were grown at 416 oC, and the room tempera-ture (RT) PL full-width-at-half-maximum (FWHM) was relatively broad at 164 meV. When the AlInN nanocolumns of 1.48mm wavelength (XIn=0.92) were grown at a higher temperature of 463 oC but increasing the V/III ratio, however the RT-PL- FWHM be-came narrower to be 106 meV. InN/In0.77Al0.23N multiple quantum well (MQW) structures of 100 wells were integrated into InAlN nanocolumns, where three such samples with the different InN well widths of 3, 2 and 1 nm were grown. The RT-PL peak wave-length shifted from 1.53 to 1.2 um depending on the well layer thickness. The quantum confinement shift is theoretically analyzed.