Improved Thermal Performance of 640 nm Laser Diode Packaged by SiC Submount.

We design high-power AlGaInP laser diodes emitting at ~640 nm. AlN and SiC submounts are used as heat sinks for the laser chips. The laser diode with SiC submount showed a higher thermal rollover power of 3.9 W and higher maximum conversion efficiency of 39% at 25°C. In the range of 15 – 35°C, the two types of lasers have similar characteristic temperature T0. At higher temperatures beyond 40°C, the laser chip mounted on SiC revealed an improved T0, compared to that on AlN. By measuring the wavelength drift of the two types of lasers, we estimate the thermal resistance to be 9.1 K/W for the laser diode on AlN and 5.6 K/W for the laser diode on SiC. [ABSTRACT FROM AUTHOR]