High power operations of 980 nm Ga_0.8In_0.2As/Ga_xIn_1-xAs _yP_1-y/Ga_0.51In_0.49P/GaAs pump lasers prepared by multi-step metalorganic vapor phase epitaxial growth with ion implanted channels

The silicon (Si) or boron (B) implantation process in Ga_0.8In_0.2As/Ga_xIn_1-xAs _yP_1-y/Ga_0.51In_0.49P/GaAs quantum well structures can be used not only for maintaining single lateral mode during high power operation but also for increasing the catastrophic optical damage (COD) level of 980 nm pump lasers. The fabricated 980 nm pump lasers with partially ion implanted channels after ridge waveguide structure formation exhibited high power operation up to 250 mW without any kink and beam steering. A photoluminescence peak shift of 70meV was obtained by 120keV Si-implantation and annealing at 900°C. Improvement of the COD level by a minimum of 1.65 times is obtained by forming transparent windows near facets by Si implantation and annealing. A highly nonradiative polycrystalline phase of the active area may be the major cause of COD failure in the Al-free 980 nm lasers.