High-power laser diodes with dry-etched mirror facets and integrated monitor photodiodes

High-power broad-area InGaAs-AlGaAs-GaAs single-quantum-well separate-confi nement heterostructure (SQW-GRINSCH) lasers with dry-etched mirror facets a nd integrated monitor photodiodes have been investigated. A multilayer resi st system has been employed as a mask for the chemically assisted ion-beam etching (CAIBE) process resulting in vertical and smooth laser facets. Thic k electroplated gold layers on top of the ohmic contacts improve the heatsi nking of the lasers leading to reasonable continuous-wave (CW) output power s even when the devices are mounted junction-side up. Monolithically integr ated monitor photodiodes provide a linear response to the optical output po wers of the laser diodes. The properties of broad-area lasers with dry-etch ed and cleaved facets are almost identical. Record values for the CW output powers of 2.59 W per uncoated facet and wall-plug efficiencies of more tha n 55% have been achieved with junction-side-down mounted devices.