Thermal and source bumps utilizing carbon nanotubes for flip-chip high power amplifiers

Carbon nanotubes (CNTs) have been successfully developed as thermal and source bumps for flip-chip high power amplifiers (HPAs). The newly developed 15 mum long CNT bumps exhibit thermal conductivity of 1400 W/m-K. A flip-chip AlGaN/GaN HEMT HPA with a gate width of 2.4 mm utilizing CNT bumps, operating voltage of 40 V, exhibits an output power of 39 dBm at, a frequency of 2.1 GHz without any degradation due to heat-up. To our knowledge, this is the first report about, a practical application of CNTs using their high thermal conductivity