Performance of AlGaN/GaN HFETs Fabricated on 100mm Silicon Substrates for Wireless Basestation Applications

Abstract — Third generation wireless communications standards such as W-CDMA place challenging requirements on microwave power transistors. To date, these challenges have been addressed with two primary technologies, Si LDMOS FETs and GaAs FETs. A new technology (AlGaN/GaN HFET) that shows the potential for addressing these strict system requirements is now becoming available. The growth and fabrication of GaN-based HFETs on a manufacturable 100mm silicon platform are discussed. Results from 36mm GaN HFETs are reported with particular attention to their ability to address the needs of the W-CDMA base transceiver station output power stage, demonstrating in excess of 15W output power at W-CDMA operation with – 39dBc ACPR and 29 % drain efficiency. Results of initial high-temperature operating life testing are presented, showing excellent device stability at a junction temperature of 200ºC, and predicting about 10 % drift in DC parameters and less than 1 dB in output power over a 20-year life. Index Terms — W-CDMA, gallium nitride, RF power transistor, ACPR, reliabilit