Effects of Total Ionizing Dose on Low Frequency Noise Characteristics in SiGe HBT

In this paper, we present low frequency noise characteristics and ionization total dose effect of three types of silicon germanium heterojunction bipolar transistors in 0.35μm SiGe BiCMOS process. We demonstrate the noise measurement details and the theoretical background along with the low frequency noise characterization. l/f noise and generation-recombination noise are extracted from the base current noise spectra. and their bias and geometries dependencies are studied. Finally, the degradation of each low frequency noise component with total dose accumulation was analyzed. Before and after irradiation, the electrical parameters and noise characteristics of three types of SiGe HBTs were significantly degraded. It is found that the low frequency noise dominated by different noise components will show different ionizing radiation effects, and the low frequency noise dominated by 1/f noise is sensitive to ionizing radiation, which is consistent with the degradation of base current.