Increasing the output power of single 808-nm laser diodes using diamond submounts produced by microwave plasma chemical vapour deposition

We have designed and fabricated submounts from synthetic diamond grown by microwave plasma chemical vapour deposition and developed an economical process for metallising such submounts. Laser diode chips having an 808-nm emission wavelength, 3-mm-long cavity and 130-mm-wide stripe contact were mounted on copper heat sinks with the use of diamond submounts differing in quality. The devices were tested for more than 150 h in continuous mode at an output power of 8 W on diamond with a thermal conductivity of 700 W m^-1 K^-1, and no changes in their output power were detected. On diamond with a thermal conductivity of 1600 W m^-1 K^-1, stable cw operation for 24 h at an output power of 12 W was demonstrated.