Non linear behavior of power HBT

Kim, Woonyun ; Kang, Sanghoon ; Lee, Kyungho ; Chung, Minchul ; Kim, Bumman (2001) Non linear behavior of power HBT. In: Gallium Arsenide applications symposium. Gaas 2001, 24-28 September 2001, London.
Full text available as:
Download (241kB) | Preview


To understand the linear characteristics of HBT more accurately, an analytical nonlinear HBT model using Volterra Series analysis is developed. The model considers four nonlinear components: rπ, Cdiff , Cdepl, and gm. It shows that nonlinearities of rπ and Cdiff are almost completely cancelled by gm nonlinearity at all frequencies. The residual gm nonlinearity are highly degenerated by the input impedances. Therefore, rπ, Cπ and gm nonlinearities generate less IM3 than Cbc. If Cbc is linearized, Cdepl and gm are the main nonlinear sources of HBT, and Cdepl becomes very important at a high frequency. It was also found that the degeneration resistor, RE, is more effective than RB for reducing gm nonlinearity. This analysis also provides the dependency of the source second harmonic impedance on the linearity of HBT. The IM3 of HBT is significantly reduced by setting the second harmonic impedance of ZS,2ω2 = 0 and ZS,ω2-ω1 = 0.

Document type
Conference or Workshop Item (Paper)
Kim, Woonyun
Kang, Sanghoon
Lee, Kyungho
Chung, Minchul
Kim, Bumman
UHF bipolar transistors, Volterra series, heterojunction bipolar transistors, intermodulation distortion, power bipolar transistors, semiconductor device models, UHF, Volterra-series analysis, analytical nonlinear model, degeneration resistor, heterojunction bipolar transistor, input circuit impedances, nonlinear behavior, nonlinear components, power HBTs, source second harmonic impedances, third-order intermodulation
Deposit date
17 Jun 2004
Last modified
17 Feb 2016 13:34

Other metadata



Staff only: View the document