Influence of group III and group V partial pressures on the size and density of InGaN quantum dots in MOVPE

Abstract

InGaN quantum dots (QDs) were grown on GaN templates in the Stranski–Krastanov growth mode at 675 °C via metalorganic vapor phase epitaxy (MOVPE). Typically, QDs with overall density of 109 cm−2, an average diameter 50 nm and average height of 7 nm were obtained. A systemic investigation on the influence of group III and group V partial pressure on the size and distribution of the InGaN QDs is reported. A higher growth rate and/or higher V/III ratio increases the mean height and the density of QDs. The distribution of the dots is found to scale with growth rate and the V/III ratio. This is attributed to a reduction in the surface diffusion of adatoms as the results of increase in partial pressure of the precursor in the reactor.