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

摘要

High In content In_xAl_(1-x) N nanocolumns were successfully self-assembled on Si (111) substrates under nitrogen-rich conditions, by rf-plasma assisted molecular beam epitaxy. The InAlN nanocolumns (X_(In)=0.87) were grown at 416 ℃, and the room temperature (RT) PL full-width-at-half-maximum (FWHM) was relatively broad at 164 meV. When the AlInN nanocolumns of 1.48μm wavelength (X_(In)=0.92) were grown at a higher temperature of 463 ℃ but increasing the V/III ratio, however the RT-PL-FWHM became narrower to be 106 meV. InN/In_(0.77)Al_(0.23)N multiple quantum well (MQW) structures of 100 wells were integrated into InAIN nanocolumns, where three such samples with the different InN well widths of 3, 2 and 1 nm were grown. The RT-PL peak wavelength shifted from 1.53 to 1.2 μm depending on the well layer thickness. The quantum confinement shift is theoretically analyzed.