Theoretical and experimental analysis of current spreading in AlGaInP light emitting diodes

The profile of light emission from aluminum gallium indium phosphide AlGaInP light emitting diodes has been studied and compared with the theoretical modeling of current spreading using a lossy transmission line model of current injected into the active region. Discrepancies between the experimentally determined emission profile and the theoretically predicted current injected into the active region have been analyzed and explained using a Monte Carlo ray tracing simulation which considers the trajectories of the photons after leaving the active region and the particular geometry of the device current, die size, and current spreading layer resistance upon the emitted emission profile. The combination of the current spreading and ray tracing models give very good agreement with the experimental emission profiles for both thin and thick current spreading layers. © 2006 American Institute of Physics. DOI: 10.1063/1.2358396