Patent ID: 7233713

Claim:
A method, comprising: forming a semiconductor laser on a laser substrate, the laser including a laser waveguide segment; forming a laser end face at a distal end of the laser waveguide segment by reactive ion etching so as to leave an outwardly protruding portion of the laser end face extending along the laser substrate from a bottom portion of the laser end face; depositing waveguide cladding material on the substrate so as to form a waveguide lower cladding layer; depositing waveguide core material over the lower cladding layer so as to form a waveguide core; and depositing waveguide cladding material over the waveguide core material and the lower cladding layer so as to form a waveguide upper cladding layer, thereby forming a planar optical waveguide on the laser substrate and the laser end face, the planar optical waveguide being end-coupled at its proximal end to the laser waveguide segment through the laser end face, the end-coupled planar optical waveguide comprising the lower cladding layer, the waveguide core, and the upper cladding layer, wherein: the outwardly protruding portion of the laser end face extends beneath a proximal portion of the end-coupled waveguide; and at least one layer of the end-coupled waveguide decreases in thickness toward the laser end face, the outwardly protruding portion of the laser end face and the decreasing layer thickness together yielding a desired layer surface profile for at least one layer of the end-coupled waveguide.