Low Temperature Gold-to-Gold Bonded Semiconductor Disk Laser

We present a gold-to-gold bonding method that combines features of surface activated bonding and capillary bonding. The process is performed at a relatively low temperature of 150°C and therefore allows the integration of materials with highly mismatched coefficients of thermal expansion. In this letter, the potential of this technique is illustrated by assembling a high-power flip chip semiconductor disk laser utilizing a chemical vapor deposition diamond heat spreader. The laser produces up to 14 W of output power at 15°C gain element temperature with a nearly diffraction-limited output beam. Further scaling of bonding area to wafer-level could make this method useful in the packaging of various optoelectronic and microelectronic components.