The second PL QW 212 and the EL QW 214 may be formed using the conventional epitaxial deposition techniques described above. The second PL QW 212 and the EL QW 214 may comprise InGaN/GaN. In an example, the second PL QW 212 may emit a red light having a wavelength of approximately 610 nm. In an example, the EL QW 214 may emit a blue light having a wavelength of approximately 440 nm. The EL QW 214 may be separated from the second PL QW 210 by a second distance D₂ of the n-type layer 204. The second PL QW 212 may be separated from the PL QW 206 by a third distance D₃ of the n-type layer 204. The second distance D₂ may range from approximately 5 nm to approximately 1000 nm. The third distance D₃ may range from approximately 5 nm to approximately 1000 nm. It should be noted that the second distance D₂ and the third distance D₃ may comprise additional layers of n-type material grown at temperature low enough to not degrade the optical properties of the layers beneath it.

The optimum layer thickness, doping, and growth conditions for the PL QWs may not be the same as those parameters in an electrically injected LED of the same color. The PL QWs and/or barriers thereof may be doped with donors such as Si or Ge in order to prevent any significant voltage drop across the PL QW region when the p-n junction surrounding the EL active region is in forward bias.