Analysis of Thermal Resistance and Heat Removal in Mesa and Etch-and-Refill Planar IMPATT Diodes

摘要

The thermal resistance of planar IMPATT diodes was compared to that of Mesa structures, and its dependence on diode diameter and thickness of the substrate calculated. The analysis shows that planar diodes always possess lower thermal resistances than mesa diodes, provided the distance from the junction to the heat sink is identical in both cases. The advantage of planar diodes for very short junction distances of 1/10 that of the junction radius, however, is minute. By increasing junction distances from the heat sink, the advantage of planar configurations becomes more pronounced; ultimately, planar diodes are expected to show higher power densities and efficiencies than mesa structures. (Author)