High-power GaAs close-confinement laser diodes

The fabrication and characteristics of high-power close-confinement GaAs laser diodes are described. Single-pellet devices emitting up to 100 watts peak power at 300°K and multiple-pellet units emitting up to 250 watts peak power are detailed. All diodes were fabricated from GaAlAs-GaAs, heterostructure wafers that were prepared by liquid phase epitaxy. The parameters considered in the design of these devices are discussed in detail and the test equipment and measurement techniques used in their characterization are outlined. Test results showing lasing threshold current density, peak optical power output, conversion efficiency, and emitted beam patterns for these devices are presented. Reliability data relating to long-term operational life and mechanical and environmental testing is also presented. A comparison is made of the gradual degradation of units operated at a current density of 50,000 A/cm²with units operated at reduced (30,000 A/cm²) drive currents.