Degradation of GaP red electroluminescent diodes has been significantly reduced by a chemical passivation of the surface. Chemical passivation was accomplished by heating the completed diodes in a solution of hydrogen peroxide which was shown to produce a native oxide surface film which is believed to be principally an amorphous form of hydrated gallium oxide. The degradation of the external electroluminescent quantum efficiency of passivated diodes at elevated temperatures has been studied and yields a predicted roomhyphen;temperature halfhyphen;life of 108ndash;109h. The results suggest that this native oxide film can act as a getter for impurities and as a barrier against the transport of impurities into the bulk material.
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