Modelling of γ-radiation effects in bipolar transistors with VHDL-AMS

This paper presents an application of the VHDL-AMS modelling language to the characterisation of γ-radiation effects on bipolar transistors. The model is based on the Gummel-Poon bipolar transistor model and takes the radiation induced effects into account on parameter level. It is shown that the γ-radiation induced effects on the transistor´s performance can be modelled by implementing a specific set of model parameters as dose dependent functions. Two different devices were modelled with this approach, a COTS matched pair bipolar transistor and a commercially available 0.35μm SiGe BiCMOS process. It is shown that both devices can be modelled within reasonable accuracy with the proposed VHDL-AMS radiation aware bipolar transistor model.