Microprocessor Thermal Analysis using the Finite Element Method

The microelectronics industry is pursuing many options to sustain the performance improvement expected every two years. One method for performance improvement is scaling transistor sizes down such that many more transistors can be compacted on chip. The on-chip temperature is a concern because the reliability and performance can be degraded due to hot spots. Thermal modeling of the chip will allow the designer to view the hot spots and adjust the architecture to obtain a reliable chip architecture. In order to meet the performance demands of the current consumer market, the trend towards multicore processors is causing thermal effects to become increasingly important. The method of thermal analysis implementation is evaluated to determine the benefits of the different approaches. The finite element analysis was ultimately chosen and used to perform a case study on a microprocessor, and to evaluate different floorplans for multicore processors. These simple floorplan evaluations are a step towards obtaining a thermallyaware multicore chip platform that can be further evaluated once the detailed layout/floorplan has been established. Heat and hot spots are a challenge in the development of emerging 3D microprocessors. While these challenges are more applicable for high performance applications, designing the 3D chip’s floorplan to take heat into account could prevent poor performance in 3D low power processors as well. Tackling thermal analysis for 3D microprocessors and creating thermally-aware 3D chips is the next step in microprocessor thermal analysis and design. Keywords— Thermal Analysis, Finite Element, Microprocessor, Multicore, On-chip temperature