New results of steady-state two-dimensional finite-element computations of temperature distributions of high power semiconductor
laser arrays are presented. The influence of different thermal loads on the 2D temperature distribution in AlGaAs/GaAs gain-guided laser arrays is investigated. TheFEM model is tested by comparing it with analytical solutions. For numerical convenience, the latter is rewritten in a novel
form, which is free of overflow problems. The maximum temperatures calculated by both methods agree within 1%. Several factors
determining the thermal resistance of the device are quantitatively examined: the ratio of light emitting to non-emitting
areas along the active zone, the amount of Joule losses, the current spreading, the solder thickness, and voids in the solder.
This yields design rules for optimum thermal performance.