Design of coplanar power amplifiers for MM-wave system applications including thermal aspects

Due to the poor thermal conductivity of GaAs, successful power amplifier design in coplanar technology requires careful thermal considerations. The influences of the active device geometry and mounting conditions have been investigated theoretically and experimentally to provide reliable thermal management design data. 50-æm thinning and flip-chip with thermal bump attachment on AIN or diamond exhibited temperature rises in the order of 50 and 40-30øC respectively, leading to significant improvement in the performance of coplanar power devices and circuits. These results demonstrate the potential of coplanar MMIC technology for high power applications.