A light emitting device includes a region of first conductivity type, a region
of second conductivity type, an active region, and an electrode. The active region
is disposed between the region of first conductivity type and the region of second
conductivity type and the region of second conductivity type is disposed between
the active region and the electrode. The active region has a total thickness less
than or equal to about 0.25n and has a portion located between
about 0.6n and 0.75n from the electrode, where
n is the wavelength of light emitted by the active region in
the region of second conductivity type. In some embodiments, the active region
includes a plurality of clusters, with a portion of a first cluster located between
about 0.6n and 0.75n from the electrode and
a portion of a second cluster located between about 1.2n and
1.35n from the electrode.
