Simple method for modeling thermoelectric cooler (TEC) performance of single-emitter semiconductor-laser packages with concentrated heat sources

High-power single-emitter semiconductor lasers may dissipate up to several Watts heat load during operation. The heat may be generated from a narrow stripe, as low as a few microns in width by several millimeters in length. Thermoelectric Coolers (TEC) are widely deployed to control the laser junction temperature in single-emitter semiconductor-laser packages. TEC manufacturers supply performance curves under the assumption of uniform heat load applied to the cold plate. In reality, the heat will spread laterally across the cold plate creating a temperature gradient across the couples. Consequently, the actual performance of the TEC may be significantly degraded as compared to that predicted from the manufacturer's guidelines. A quantitative analysis that includes these deviations is necessary to properly size the TEC and optimize the package design. This paper provides a simple method for modeling the TEC performance parameters on concentrated heat loads using commercially-available FEA software. Experimental data of TEC cooled single-emitter laser packages will also be presented that corroborate the results of our model.