ASYMMETRIC CLADDING-RIDGE WAVE-GUIDE LASER BY SELECTIVE-AREA MOCVD

Ridge waveguide lasers with a thin upper cladding layer are fabricated with a two-step selective-area MOCVD growth. The lower cladding, active region, and upper cladding are all grown in the initial MOCVD growth. A second growth over an oxide pattern is used to define the ridge with 0.15 mu m of GaAs, which serves as both the contact and index increasing layer. Ridge lasers fabricated by this method (3 x 425 mu m) have a cw threshold current of 12.6 mA, slope efficiency of 0.26 W/A, and operate in a fundamental transverse mode as well as stable fundamental lateral mode to 20 times threshold.