Calculation of the thermal resistance and temperature distribution in blue-green semiconductor lasers

The thermal resistance (R-t) for Zn(x)Mg(1-x)SySe(1-y)/ZnSZSe1-Z/ZnyCd1-ySe lasers is calculated using a two-dimensional heat-flow model. Calculation was done considering various heat sources and taking into account the thickness and the thermal conductivity of the layers forming the heterostructure. The Rt values thus obtained agree quite well with the experimental values reported for this structure. Our model provides better results than a previous one in which the whole structure was considered as a homogeneous medium. The temperature distribution in the laser structure is calculated analysing the influence of the voltage drop at the Au/p-ZnSe interface. The dependence of the thermal resistance on the cavity length and the stripe width is also discussed.