Modeling and extraction of SiGe HBT noise parameters from measured Y-parameters and accounting for noise correlation

Abstract

The technique to extract the SiGe HBT noise parameters only from the measured y-parameters is extended to account for the presence of noise correlation. Unlike earlier publications, this method does not need to fit the noise transit time to measured noise data. The technique was validated using 2D device simulations and measured noise parameter data. It was found that the NFMIN of SiGe HBTs with fT /fMAX of 160 GHz is approximately 1 dB lower at 60 GHz when noise correlation is accounted for. However, for these devices noise correlation proves to be insignificant below 18 GHz.

Procedure to derive analytical models for microwave noise performances of Si/SiGe:C and InP/InGaAs heterojunction bipolar transistors

“…The Ge content of the 30 nm thick base is gradual varying from 10% to 30% from emitter to collector side. The emitter surface (S E ) is equal to 0.17 × 5.7 μm 2 . More details about the device technology and conception can be found in [26].…”

“…For one decade, heterojunction bipolar transistors (HBT) have reached outstanding high frequency noise (HFN) performances. Analytical models for HFN analysis are useful for developing guidelines to further improve the HBT noise levels; however, these relations are often very complex, see for instance [1][2][3] or relations (28) and (29) in this work. Hence, it is advantageous to develop formulas as accurate and simple as possible to identify and quantify the main contributions to HFN.…”

Comparison of High-frequency Noise Correlation Models in SiGe HBTs

“…2. By this method, we obtain the expressions of the four circuit level noise parameters as functions of <i n 2 >, <v n 2 >and <v n i n *> [5], [7].The minimum noise figure:…”

“…The transistors' noise can degrade the performance of mobile wireless receivers and prevent amplifiers and oscillators from meeting the stringent requirements in GHz frequency range [2]. As the wireless communication market grew rapidly, a number of publications on high-frequency noise modeling of Si/SiGe HBTs were induced during the last few years [3]- [5]. Models of transistors noise figure were developed using a small signal equivalent circuit together, and various analytical equations were used to determine the minimum noise figure NF min as a function of bias conditions and transistor parameters [3], [4], [6].…”

SiGe BiCMOS for Analog, High-Speed Digital and Millimetre-Wave Applications Beyond 50 GHz

“…30 reproduces the measured NF MIN at 5 GHz and at 65 GHz in HBTs with f MAX of 200 GHz and 300 GHz, respectively. NF MIN was obtained from Y-parameter measurements as in [35], [39]. The impact of transistor vertical profile scaling on NF MIN is negligible at 5 GHz but becomes significant at 65 GHz.…”