Two stage monolithic thin film coolers

Optoelectronic devices such as vertical cavity surface emitting lasers (VCSEL´s) generate large heat power densities on the order of 100´s of W/cm². A novel device structure consisting of a two-stage monolithically integrated thin film thermionic and thermoelectric cooler is proposed to accommodate these cooling requirements. By optimizing the geometry of each stage, improved heat spreading can be achieved resulting in an increase of the cooling power density. The two-stage, three terminal structure is investigated experimentally. Cooling power densities of 100´s W/cm² have been demonstrated in III-V semiconductor material systems proving that the integration of these coolers with optoelectronic devices should be possible