A simple method to accurately determine the temperature dependence of thermal resistance of InP HBTs

A simple method to accurately determine the nonlinear dependence of the thermal resistance of heterojunction bipolar transistors (HBTs) on ambient and junction temperatures is presented. A nonlinear model of the thermal resistance dependence on the power dissipation is introduced for the actual junction temperature predicting. This method is demonstrated by an accurate extraction of thermal effects of a power HBT with an effective emitter area of 1×15μm
²
, fabricated with an in-house InP HBT technology.