LOW-FREQUENCY NOISE PROPERTIES OF SIGE HBTS AND APPLICATION TO ULTRA-LOW PHASE-NOISE OSCILLATORS

This paper presents an extensive electrical characterization of Si/SiG e/Si heterojunction bipolar transistors (HBT's) grown by molecular bea m epitaxy (MBE). These devices are designed for microwave and millimet er-wave applications since they present a maximum oscillation frequenc y in the 40-GHz range, The processing technology, featuring a high-qua lity oxide passivation, results in ideal Gummel plots and an input noi se corner frequency of 250 Hz at lowest. A dielectric resonator oscill ator (DRO) at 4.7 GHz has, therefore, been realized. The measured phas e-noise level of this oscillator is below -135 dBc/Hz at 10-kHz offset frequency, which is at least 10 dB better than the best FET or HBT st ate-of-the-art DRO's.