Prospects of using self-assembled GaN/AlN quantum dots for universal memory elements

Abstract

The possibility of using self-assembled GaN/AlN quantum dots (SAQDs) for universal memory elements is considered. The energy spectrum of GaN/AlN SAQDs was calculated to reveal the dependence of the electron localization energy (E_loc) on their sizes and elastic deformation. The calculations took into account the effects of strain, spontaneous and piezo-polarization and the quantum confinement effect. The energy spectrum calculations were performed in the 8-band k × p approach. The vertical and longitudinal sizes of the SAQDs were varied over a wide range. To verify the calculations, the calculated SAQDs optical transition energy was compared with the photoluminescence data and information on the SAQDs sizes available in the literature. It was shown that the pseudomorphically strained SAQDs with height >2–3.5 nm (depending on the aspect ratio) are characterized by the electron localization energy value of more than 1.5 eV. According to the literature data, the formation of pseudomorphically strained SAQDs with these sizes is possible, and it makes GaN/AlN SAQDs promising for the fabrication of memory devices with a charge storage time of more than 10 years.