Steady-state and dynamic thermal models for heat flow analysis of silicon-on-insulator MOSFETs

Self-heating in silicon-on-insulator (SOI) MOSFETs has become one of the vital issues for design, characterization, optimization and reliability prediction of SOI devices and integrated circuits due to the low thermal conductive buried oxide (BOX) and the continual increase in the microelectronic packaging density. Thermal models that are accurate and detailed enough to provide device temperature profiles and efficient enough for large scale electro-thermal simulation are therefore strongly desirable. This paper discusses the fundamental concepts for modeling of heat flow in semiconductor devices. A brief overview for the conventional approaches to thermal modeling of the SOI devices is given. Improved steady-state and dynamic SOI heat flow models based on the SOI film thermal resistance for efficient prediction of steady-state and dynamic temperature variations in SOI devices are presented. These improved models are applied to investigate temperature distributions and temporal evolution of the junction temperature in SOI nMOSFETs.