Large-signal HBT model with improved collector transit time formulation for GaAs and InP technologies

Large-Signal Modeling of High-Speed InP DHBTs using Electromagnetic Simulation Based De-embedding

“…The large-signal model employed in this paper is based on the modified UCSD model implemented in Agilent ADS 2004A [3], [7]. The equivalent circuit for the intrinsic and extrinsic elements is shown in Fig.4.…”

“…An accurate and consistent formulation of the carrier transit time in the HBT model is not easily obtained from the transit time and input capacitance integral in case of high-speed HBT devices [3], [9]. This is partially due to the fact that it is insufficient to determine the diffusion charge from the simple product of the transit time and the current.…”

“…Unlike Silicon based transistors, InP DHBTs have a non-monotonic electron velocity-field characteristics. This affects the collector transit time and leads to a complicated bias dependence for the cutoff frequency ft and the base-collector capacitance Cb, [3]. In order to fully exploit the potential offered by InP DHBT technology, accurate large-signal models are needed for circuit design.…”

Determining the base resistance of InP HBTs: An evaluation of methods and structures

“…This is a problem in InP HBTs since the base current is dominated by recombination rather than backinjection [40]. While it is possible and common, even in dedicated III-V compact models [41], to model it using traditional diode equations, a single ideal diode is usually not sufficient and the required ideal region for I B is almost non-existent at medium and high forward bias. Third, the bias dependence of R Bi does not cancel with that of 1=B f .…”

An empirical DC to high-frequency model for InP/InGaAs HBTs

“…To predict the HBT characteristics, several physics-based HBT nonlinear models, such as VBIC (McAndrew et al, 1995;Wei, Gering, & Tkachenko, 2005), HICUM (Rein & Schroter, 1987;Stubing & Rein, 1987), MEXTRAM (Degraaff & Kloosterman, 1985), FBH (Rudolph, Doerner, Beilenhoff, & Heymann, 2000) and Agilent (Iwamoto, Root, Scott, & Cognata, 2003), have been reported, and many integrated circuit design tools have already incorporated those models.…”