Effects of depletion on the emission from individual InGaN dots

Abstract

We report a photoluminescence (PL) study of the effects of carrier depletion on the electronic states of InGaN quantum dots. Samples were fabricated into mesa devices with top Schottky contacts and back ohmic contacts. Submicrometer apertures were created lithographically. Capacitance-voltage measurements of the devices suggest that the dots are fully depleted when they are unbiased. Micro-PL studies of individual dots show narrow linewidths under zero or reverse bias conditions. Forward biasing of the junction results in broadening of the dot levels due to the populating of nearby conduction band states in the underlying quantum well. © 2006 American Institute of Physics.