A surface-emission
laser diode comprises a cavity region over a
semiconductor substrate and includes an
active layer containing at least one
quantum well
active layer producing a
laser light and a
barrier layer, a spacer layer is provided in the vicinity of the
active layer and formed of at least one material, an upper and lower reflectors are provided at a top part and a bottom part of the cavity region, the cavity region and the upper and lower reflectors form a mesa structure over the
semiconductor substrate, the upper and lower reflectors being formed of a
semiconductor distributed Bragg reflector having a periodic change of
refractive index and reflecting incident light by interference of optical
waves, at least a part of the semiconductor
distributed Bragg reflector is formed of a layer of small
refractive index of AlxGa1-xAs (0<x≦1) and a layer of large
refractive index of AlyGa1-yAs (0≦y<x≦1), the lower reflector is formed of a first lower reflector having a low-refractive index layer of AlAs and a second lower reflector formed on the first lower reflector, the second lower reflector has a low-refractive index layer of AlGaAs, any one layer constituting the cavity region contains In.