Thermal analysis of IC package burn-in subrack

Integrated circuit (IC) package manufacturing involves number of intricate process steps and is prone to defects, which will shorten product life. Hence early deduction of the defects is important for high production yield. One of the package screening tests is the burn-in test. As the IC package power drastically increased over the last decade, the design requirements of a burn-in system to provide controlled environment is more challenging. Various techniques are employed in new generation burn-in system to reduce the burn-in time and throughput. A good thermal model and analysis of the burn-in system will help the overall IC production cause. In this paper, thermal-modeling approach of a custom built burn-in system and validation plans are discussed. Methodologies for development of compact models of package and socket, solid state heat pump and sub-rack are discussed in the paper. Emphasis is also given to validate the sub-rack level numerical models by measurements using a test package in a known ambient condition. The modeling details and validation results are discussed in this paper.