Thermal Impedance Modeling of Si–Ge HBTs From Low-Frequency Small-Signal Measurements

In this letter, the thermal impedance of SiGe heterojunction bipolar transistors has been characterized using low-frequency small-signal measurements. Theoretical works for thermal impedance modeling using different electrothermal networks, developed until date, have been verified with our experimental results. We report for the first time the experimental verification of the electrothermal model for thermal impedance developed by Mnif using a nodal and recursive network. A generalized expression of the frequency-domain thermal impedance has been selected for electrical compact transistor model (HiCuM) improvement, parameter extraction, and electrothermal network verification.