This paper presents a fully integrated 8186GHz power amplifier (PA) fabricated in a 0.12 m SiGe BiCMOS technology. Three cascode stages, followed by two common-emitter stages were utilized to achieve power gain of 30dB with 12dBm output power at 1dB compression and saturated power of 14dBm. Small signal characteristics show peak gain achieved at 86GHz with both input and output matching is better than 15dB from 77GHz to 87GHz. A 40dB image rejection is accomplished by a selective notch filter also integrated on chip. The PA's bias is applied by digitally adjustable bias circuits to provide process and temperature compensation and was measured in room temperature, 50°C and 85°C. It consumes quiescent currents of 120mA and 85mA from a 2V and 2.7V supplies respectively at 1dB compression and occupies area of 1.6mm 2. © 2011 IEEE.