RF Power Semiconductors for Wireless Communications

October 31, 2003
Dr. Chuck Weitzel, Motorola, Inc., Tempe, AZ

A wide variety of semiconductor technologies (Si, SiGe, and GaAs) are used for cellphone RF power amplifiers. The performance of the devices fabricated in each of these semiconductor technologies will be compared for the various cellphone systems: GSM, DCS, CDMA, and WCDMA. Of particular interest will be power amplifier power added efficiency, linearity, operating voltage, ruggedness, and die size. Semiconductors also play an important role in cellular base station power amplifiers. At this time Si LDMOS owns this application space, but is being challenged near term by GaAs and longer term by GaN. The performance of power FETs in these technologies will also be compared.