Steady and Transient Heat Transfer Analysis of the Microprocessor System Using One-Dimensional Thermal Network

Abstract

This paper introduces and discusses one-dimensional thermal network for microprocessor silicon die temperature prediction both under steady and transient states. Firstly, one-dimensional thermal network with average temperature nodes is constructed with the thermal spreading resistance and the thermal local resistance. Secondly, characteristics of thermal resistances under steady state are discussed. By conducting three-dimensional heat conduction simulation, thermal resistance values are evaluated for the case with different cooling solutions and different heat distributions at silicon die bottom of microprocessor. Thirdly, thermal resistance behavior of introduced thermal network during transient state is explored for further understanding of temperature transition of the microprocessor silicon die. Since the thermal spreading resistance takes relatively large value and changes its value drastically, this paper investigates transient behavior of thermal spreading resistance from TIM (Thermal Interface Material) to heat sink base as an example.