A light-emitting diode includes: a semiconductor substrate; and a layered structure,
made of an AlGaInP type compound semiconductor material and provided on the semiconductor
substrate. The layered structure includes: a light-emitting structure composed
of a pair of cladding layers and an active layer for emitting light provided between
the pair of cladding layers; and a current diffusion layer which is lattice-mismatched
with the light-emitting structure. A lattice mismatch a/a of the current
diffusion layer with respect to the light-emitting structure defined by the following
expression is -1% or smaller:
a/a=(ad-ae)/ae
where ad is a lattice constant of the current diffusion layer, and
ae is a lattice constant of the light-emitting structure.
