A novel approach for an improved heat management in InP-based quantum cascade lasers

We present a novel manufacturing process which aims to improve the heat removal and to facilitate the fabrication of quantum cascade lasers. An integrated Au-heatsink just on top of the laser ridge is realised by means of a self-aligning technique which allows the fabrication of laser structures with ridge widths down to 2 mum. This geometrical configuration permits the reduction of the thermal resistance of the devices by more than 50 %, as compared to typical metal-clad-ridge-waveguide structures. The processing method completely avoids critical steps, both in the fabrication and in the mounting procedure.