Abstract: A direct band gap semiconductor compound, GaAs.sub.1-x P.sub.x, where x is less than 0.45, is doped with nitrogen for forming an array of light emitting diodes. Preferably, the light emitting junctions of the LEDs are substantially free of nitrogen, but the underlying epitaxially grown semiconductor compound is nitrogen doped. The nitrogen doping is believed to immobilize dislocations for enhancing uniformity of light output power, reducing degradation and increasing uniformity of degradation during use of the LEDs. The proportion of LED arrays rejected for nonuniformity was reduced from 40 percent to less than 8 percent by nitrogen doping the direct band gap material.