Cost-effective thermally-managed 1.55-μm VECSEL with hybrid mirror on copper substrate

An electroplated copper substrate was evaluated for heat dissipation in 1.55-μm optically pumped vertical extended cavity surface emitting lasers (OP-VECSELs). It is a cost-effective and flexible solution compared with the previously proposed chemical vapor deposition diamond substrate assembled by metallic bonding. Continuous-wave (CW) lasing operation was demonstrated from a device (with copper electroplated substrate) under optical pumping with pump spot diameter of 100 μm and a maximum output power of 260 mW at 0 °C; heatsink temperature was achieved. Room-temperature CW operation with an output power of 75 mW and an external quantum efficiency of 35% was achieved in an optimized plane-concave cavity. The thermal resistance and the maximum output power of VECSEL chips assembled with bonded bulk copper and electroplated copper substrates were measured and compared. A value of ∼50 K/W was estimated for both devices, and a similar rollover point was observed, which indicates that the electroplated copper solution leads to similar thermal properties as a bonded bulk copper substrate. © 2006 IEEE.