The Development of a Symbolically Defined Large Signal InP/GaAsSb Type-II DHBT Model for 200 GHz Mixed Signal Circuit Simulation

A large signal device model is developed for type-II InP/GaAsSb/InP devices that is based on the UIUC Type-I SDD model. The model accurately characterizes a balanced 480/420 GHz fT/fMAX device, and is used to design and simulate a 200 GHz static frequency divider. In this paper the UIUC SDD Type-II model, a large signal InP/GaAsSb type-II model developed at the University of Illinois, is presented. The model is implemented as a symbolically defined device in Agilent's Advanced Design System (ADS), and is based on the well established UIUC SDD type-I InP/InGaAs model, but has been altered to model the different charge transport phenomena that occur in type-II devices. The model is extracted for a balanced fT/fMAX type-II device fabricated at the University of Illinois and is capable of giving an excellent fit to both measured DC and RF data across the entire bias range of the device. The UIUC SDD Type-II model has been tested in high frequency mixed signal circuit simulations, through the design and simulation of a 200 GHz static frequency divider, which will be described in the paper.