Low frequency noise measurements of advanced BiCMOS SiGeC Heterojunction Bipolar Transistors used for mm-Wave to terahertz applications

In this study, we present recent low frequency noise results obtained on Si/SiGeC Heterojunction Bipolar Transistors (HBTs) associated with a 0.13μm BiCMOS technology. Two technologies are studied, referenced as A and B, with high frequency figures of merit f_T/f_MAX (unity current gain frequency/maximum oscillation frequency) 220/280 GHz for technology A and 300/400 GHz for technology B. The LF Noise measurements are performed in the 1Hz-100 kHz frequency range as a function of the base bias current and of the emitter area A_E. The 1/f noise component is studied through the SPICE LFN parameters A_F and K_F. The K_B figure of merit (K_B = K_F *A_E), used to compare the 1/f noise level, has an excellent value of 1.5 10^-10 μm² for technology A and above 6 10^-10 μm² for technology B. Dispersion of the 1/f noise level observed on technology B is associated to the presence of predominant GR components. A temperature study of the 1/f noise level evolution in the range 15-100°C was also done. The temperature dependence is week except at very low base current bias.