Phasenseparation von dünnen InGaN-Schichten in der metallorganischen Gasphasenepitaxie - Realisierung und Anwendung von InGaN Quantenpunkten

Abstract

This work is devoted to the understanding and realization of the InGaN quantum dot formation process. The growth is performed on an n-doped GaN layer in a metal organic vapor phase epitaxy reactor. Evidence has been found that spinodal and binodal decomposition are driving a separation process of a thin InGaN layer into two phases with different InN concentrations. The region with low InN content is forming the quantum dots on the surface of a GaN layer. The spinodal phase diagram has been calculated for the case of a strained InGaN layer on GaN. The accordance between theoretical and experimental results is shown. For device application it is necessary to cap these structures with a p-doped GaN layer. The influence of a GaN capping on the phase separated InGaN structures is discussed. Finally, the applications of InGaN quantum dots in LEDs, laser structures and microcavities is presented.