Patent ID: 7042016

Claim:
A semiconductor optical device comprising: a superlattice contact semiconductor region having a superlattice structure, said superlattice contact semiconductor region including a II–VI compound semiconductor region and a first II–VI compound semiconductor layer, said II–VI compound semiconductor region containing zinc, selenium and tellurium and said first II–VI compound semiconductor layer containing zinc and selenium; and a metal electrode provided on said superlattice contact semiconductor region, said metal electrode being electrically connected to said first II–VI compound semiconductor layer; wherein said II–VI compound semiconductor region includes a second II–VI compound semiconductor layer containing zinc and selenium and a third II–VI compound semiconductor layer containing zinc and tellurium, the first II–VI compound semiconductor layer is provided between the metal electrode and the third II–VI compound semiconductor layer to prevent atoms in the metal electrode from reacting with atoms in the II–VI compound semiconductor layer, and the third II–VI compound semiconductor layer is provided between the first II–VI compound semiconductor layer and the second II–VI compound semiconductor layer.