Patent ID: 7602828

Claim:
A broad-area semiconductor laser comprising: a planar substrate; an index guiding region comprising a plurality of epitaxial layers supported by the planar substrate for guiding an optical beam parallel to the substrate, the plurality of layers comprising: an active layer for providing optical gain; a first guiding layer above the active layer for providing optical confinement; a second guiding layer below the active layer for providing optical confinement; and a cap layer on the first guiding layer for supporting an electrode; first and second lateral confining regions, one on either side of, and in direct contact with the index guiding region defining a confinement width for guiding the optical beam in a lateral direction; first and second reflecting surfaces on either end of the plurality of layers defining an optical cavity; and a current injection electrode having a stripe width mounted on the cap layer above the active layer, and extending between the first and second reflecting surfaces for injecting electrical current into the active layer; wherein the confinement width is wider than the stripe width.