LATERAL CURRENT CONFINEMENT IN JUNCTION LIGHT EMITTING DIODES ESPECIALLY LASERS

摘要

LATERAL CURRENT CONFINEMENT IN JUNCTION LASERS Described is a stripe geometry double heterostructure (DH) junction laser in which lateral current confinement is achieved by pairs of laterally spaced, reverse-biased p-n junctions. A mesa is formed on an n-GaAs substrate, for example, and a layer of p-AlGaAs is then grown by LPE so that nucleation does not occur on the top of the mesa. Laterally spaced zones of p-AlGaAs are thus formed on either side of the mesa. An n-p-p or n-n-p DH is then grown so that the interface between the p-AlGaAs layers and the first n-layer of the DH forms a pair of laterally spaced p-n junctions separated by the mesa. When the lightemitting p-n junction in the DH active region is forward biased, the pair of spaced junctions are reverse biased so that pumping current is constrained to flow through the active region in a narrow channel to the mesa. Further lateral current confinement is achieved by forming on the upper DH surface a second pair of reverse biased p-n junctions separated by a window in alignment with the mesa.