dr. medi asheghi

research & development

icona technology

the trend in increased power densities for integrated systems has been accompanied by the formation of non-uniform heat generation patterns and subsequently sharp temperature gradients across a microprocessor or chip. there have been many advances in recent years in package and chip level cooling technologies; however, it appears that, with increasing power density and the associated cost for cooling schemes, we can no longer design for worst case scenarios and must take into account both local and global temperature non-uniformities. thermal management issues span from the individual device level to the system component (e.g., processor) level, thereby representing length scales that range from 10 ^-8 m to 10 ^-2 m. clearly, understanding the fundamentals of heat transport and thermal modeling as well as developing simulation and experimental tools and technqiues to cover length scales that are different by nearly six orders of magnitude would be a challenging endeavor.

this presentation provides an overview of the challenges facing the semiconductor industry and will cover topics ranging from nanoscale heat transport in microelectronic devices to the microprocessor level thermal engineering and management. in particular, we attempt to understand to what extent can small heating effects (of a single or multiple transistors) impact chip temperature distribution for circuits under full operation? in another word, what is the impact of different power granularities on global chip temperatures? in addition, we will find the required minimum granularity (finest mesh) for accurate thermal analysis of a microprocessor as well as the lengthscale that separates the nano/micro-scale (transistor level) from the macroscale (chip and package level) regime.