Effects of device design on the thermal properties of HBTs

Thermal management is of critical concern in high performance InP-based HBTs, because enhancements in RF performance are typically obtained with increased current density and aggressive device scaling. The resulting increase in junction temperature can degrade carrier transport and negatively affect overall device reliability. This paper reports an investigation of thermal resistance in InP-based HBTs with various vertical and lateral designs. Three-dimensional simulations and experimental results illustrate that significant differences in thermal resistance can arise with relatively small changes in device structure.