Origin of Luminescence from InGaN Diodes

Abstract

We report the first direct observation of phase decomposition in a luminescent alloy and show that this decomposition, allied to quantum confinement enhancements, accounts for the surprisingly high efficiency of InGaN-based diodes manufactured by Nichia Chemical Industries. Hence nanostructure, rather than composition, is responsible for the success of these devices. A common nanostructure, in the form of nearly pure InN quantum dots, occurs across a large range of average indium content in InGaN and leads to a universal scalability of the optical spectra.