Home – Home – Jornals – Avtometriya 2021 number 5

Photoluminescence of structures with multiple GaN/AlN quantum wells grown by molecular beam epitaxy has been investigated. Calculated dependence of the quantum well photoluminescence band peak energy on the thickness of the GaN layer has been compared with experiment for various ratios of the thicknesses of the GaN and AlN layers. The thicknesses of the GaN and AlN layers were determined by transmission electron microscopy. The calculations of the photoluminescence band peak energy were carried out in the 6-band kp-approximation taking into account spontaneous and piezoelectric polarizations. According to the calculation results, the slope of the dependence of the emission energy on the GaN layer thickness decreases with increase in the ratio of the GaN layer thickness to the AlN layer thickness, in accordance with decrease in the electric field in the GaN layer. In quantum wells of sufficiently large thickness the observed photoluminescence band peak energy is higher than the calculation result for undoped structures due to unintentional doping of the quantum wells, which leads to screening of the built-in electric field.