Self-Heating Characterization Techniques for Advanced RF Transistors

Due to the downscaling of transistor size, self-heating is a major issue in the microelectronics industry and not only for high-power devices. Different on-wafer characterization techniques to extract the thermal model of advanced transistors will be presented and their advantages and limitations will be discussed. Since the volume of the most advanced transistors is extremely small, their thermal time constants are quite short, on the order of nanoseconds, and thus it is mandatory to employ RF characterization techniques that properly model their thermal behavior. Thermal models available in industrial PDKs will be surveyed, as well as ways to improve them. Finally, design strategies to minimize transistor self-heating and thermal crosstalk will be demonstrated for fully depleted SOI MOSFETs.