Spectral Electroluminescence Mapping of a Blue InGaN Single Quantum Well Light-Emitting Diode

Abstract

The microscopic spectral emission characteristic of Nichia's blue InGaN single quantum well light-emitting diode is characterized by highly spatially and spectrally resolved scanning electroluminescence microscopy under operation. The electroluminescence intensity maps and the emission peak wavelength images directly image the optical quality of the device and yield quantitative mappings of the good p-contact quality as well as the small In fluctuations with a spatial resolution of 1 µm. Band filling effects, i.e. the consecutive filling of the local potential minima is visualized. A highly spectrally resolved measurement proves the existence of very sharp single emission lines from the localized states.