Low-noise performance near BV_CEO in a 200 GHz SiGe technology at different collector design points

Abstract

We explore the low-noise behavior of both high-fTand enhanced-breakdown SiGe HBTs, showing key differences as a function of VCB. Both devices achieve values for Fmin below 0.4, 1.2 and 1.4 dB at 10, 15 and 20 GHz, respectively, with corresponding GA values better than 18.5, 14.5 and 13.2 dB. In addition, the enhanced-breakdown device demonstrates the ability to operate at 1 V higher VCB compared with the high-fT device prior to the onset of avalanche-induced Fmin degradation. Combined with a lower CCB, this improved VCB range allows the device to achieve higher gain for the same or lower noise.