Accurate Prediction of Thermal Resistance of FET by Detailed Modeling of Heat Generation and Backend Stackup

In typical thermal modeling of a FET (field effect transistor) structure, the power could be modeled as the heat generation, which is averaged under the entire gate length (gate averaged). However, it is found from the electrical potential field within the channel that the heat generation is actually distributed all the way from source to drain with a heavy concentration around the gate edge at the drain side. In a typical case, the peak of the heat distribution is almost four times of the gate averaged. Therefore, accurate modeling of the heat generation averaging over a much smaller region near the gate edge (edge averaged) makes a significant difference. This paper focuses on the comparison of the edge averaged versus the gate averaged modeling development. Furthermore, the detailed topology of the backend stackup layers and their relative impacts on heat dissipation paths are evaluated and the practical simplification is proposed in the modeling development. The result shows that, for a single gate FE...