In situ selective etching and selective regrowth of epitaxial layer for surface recombination velocity reduction in light emitting diodes

Abstract

LED apparatuses featuring etched mesas and techniques for manufacturing LED apparatuses are described, including techniques for reducing surface recombination and techniques for charge carrier confinement. Etched facets of an LED mesa can be passivated using epitaxial regrowth of one or more semiconductor regrowth layers. The one or more semiconductor regrowth layers can include a transition layer. The transition layer can be configured with a bandgap energy between that of layers that are on opposite sides of the transition layer. A transition layer can separate an etched facet and another regrowth layer or separate two regrowth layers. In some instances, selective etching can be performed to preferentially etch a quantum well layer relative to a barrier layer. The selective etching removes surface imperfections, which contribute to surface recombination and which tend to be more prevalent in etched facets of the quantum well layer than etched facets of the barrier layer.