High-reliability blue-shifted InGaAsP/InP lasers

InGaAsP/InP quantum well (QW) ridge waveguide lasers emitting nominally at 1310 nm have been ‘‘blue‐shifted’’ selectively (as much as 70 nm) on a full 50‐mm‐diameter wafer after growth. P+ ion implantation at 1 MeV, 200 °C through a variable thickness SiO2 mask was used to induce various degrees of QW intermixing after postimplantation annealing at 700 °C. Irrespective of the amount of intermixing induced (blue shift), all fabricated devices exhibited 20–25 mA lasing threshold current and 0.25–0.30 W/A differential quantum efficiency. Device reliability was equivalent to standard (nonimplanted) lasers when the wavelength shift was 35 nm or less, corresponding to predicted lifetime in excess of 25 years while operating cw at 25 °C. The performance and reliability data clearly indicate that the concentration of residual defects introduced in the active region by the implantation/annealing process is negligibly small. The present results, which are a product of a straightforward fabrication process, suggest ...