Thermal Analysis of VLSI System: A Simulation Study

Smaller size of Very Large Scale Integrated (VLSI) System nowadays increases the
on chip power densities causing the rise of temperature in the system. The high
temperature produced will eventually affects the clock frequency of the system and
changes the timing setup of the component. These lead to lowering the performance
and reliability of the system. Due to the negative effects of the high temperature,
designers have to determine the thermal profile of the systems in order to understand
the temperature distribution, the leakage reduction and estimate the power distribution
of the system. This research focuses on analyzing the thermal profile of a VLSI system
under steady state condition using numerical techniques and simulation. For the
numerical techniques, the governing heat equation for a two-dimensional (2D) model
was solved using Finite Difference Method (FDM), Gauss-Seidel (GS) and Successive
Over Relaxation (SOR) methods. Simulation based on ANSYS simulator has been
conducted for validation purpose. Most commonly material used in VLSI system
which is Silicon (Si) is tested under adiabatic condition. The results for numerical
techniques and the simulation are compared. SOR method shows better results in terms
of number of iterations and the computational time compared to GS method in solving
the governing heat equation. Both methods have the same maximum temperature and
these temperatures are comparable with the result obtained by using ANSYS.