Class-A stacked SiGe HBT power amplifier at millimeter-wave

The advancement of silicon-based transistor´s f_T and f_MAX have ushered in a new contender in the area of millimeter-wave integrated circuit technology [1], [2]. Silicon´s greatest advantage over III-V based technologies, to integrate both digital and RF functions onto a single chip, has been demonstrated successfully across the millimeter-wave spectrum [3]-[5]. However, one of silicon´s greatest weaknesses, low breakdown voltages, prevents the implementation of a quality power amplifier at millimeter-wave frequencies [6]. This paper discusses a millimeter-wave power amplifier implemented using a stacked transistor architecture known as the High Voltage / High Power (HiVP) configuration [7]. Using this configuration, a silicon-based amplifier achieving an output power of 19 dBm with 11.47% PAE in 0.23 mm² of area, has been created using a commercial 120 nm SiGe HBT BiCMOS process. Unique to this implementation, this class-A amplifier achieves a 50 Ω match at 30 GHz while offering a new amplifier architecture ready for single chip integration [8], [9].