A GaNp‐njunction structure was grown on a (0001) sapphire substrate by atmospheric pressure metalorganic chemical vapor deposition using a double buffer layer. The resulting light emitting diode (LED) was further exposed to a low‐energy electron beam source. The effect of e‐beam exposure on the room‐temperature electroluminescence spectra of the LED is reported. It is found that the electroluminescence spectral features change dramatically as a function of the electron‐beam exposure time and current density. This is attributed to changes in active Mg concentration. The origin of each electroluminescence band is discussed. ©1996 American Institute of Physics.