Optimization of 660-nm-Band AlGaInP Laser Diodes by Using Deep-Level Transient Spectroscopy Analyses

We report high power and high temperature operation of 660-nm-band AlGaInP laser diodes. The double-channel ridge waveguide structure was used, and the growth conditions for each layer of the AlGaInP laser were optimized to have the lowest defect density by using deep-level transient spectroscopy (DLTS) analyses. The optimized AlGaInP lasers showed better performance than those fabricated without optimization. One of the optimized AlGaInP lasers showed a very stable fundamental transverse mode even at 200 mW and 70 ◦C, a typical threshold current of 64 mA at 660 nm, a slope efficiency of 1.0 W/A, and a characteristic temperature of 212 K. The beam divergences perpendicular and parallel to the junction plane were 15.3◦ and 8.6◦, respectively, at 80 mW CW, which is small enough for a DVD-R/RW system.