Large signal modelling of GaAs/AlGaAs HBT's with separation of the surface recombination current (original) (raw)

Large-Signal Modeling of High-Voltage GaAs Power HBTs

IEEE MTT-S International Microwave Symposium Digest, 2005., 2005

This paper presents modeling results for newly developed InGaP/GaAs power HBTs operating at bias voltages up to VCE = 26 V. The devices are flip-chip mounted for heat-sinking and deliver output powers above 10 W. It is shown that the FBH HBT model is capable of describing those devices despite the fact that it was developed originally for standard 'low-voltage'

New GaInP/GaAS-HBT Large-Signal Model for Power Applications

28th European Microwave Conference, 1998, 1998

A new GaInP/GaAs HBT model for power applications is presented. It is based on the GUMMEL-POON model. Additionally, it accounts for the increase of the thermal resistance at high temperatures and the high collector-current base push-out effect. The model is validated for GaInP/GaAs HBTs.

An accurate and compact large signal model for III–V HBT devices

Solid-State Electronics, 2005

An accurate and compact large signal model is proposed for modeling heterojunction bipolar transistors (HBTs) based on III-V materials. In DC mode, the model includes self-heating, Kirk and Early effects, as well as the temperature dependence of the model parameters. In small signal mode, the model captures the variation of various AC parameters with bias. The procedure of extracting the model parameters uses DC and multiple bias S-parameter measurements. The model is compiled in the HP-ADS circuit simulator as user-compiled model and is verified by comparing its simulations to measurements in all modes of operation for an AlGaAs/GaAs transistor with an emitter area of 2 · 25 lm 2 .

Scalable GaInP/GaAs HBT large-signal model

IEEE Transactions on Microwave Theory and Techniques, 2000

A scalable large-signal model for heterojunction bipolar transistors (HBTs) is presented in this paper. It allows exact modeling of all transistor parameters from single-finger elementary cells to multifinger power devices. The scaling rules are given in detail. The model includes a new collector description, which accounts for modulation of base-collector capacitance Cjc as well as for base and collector transit

Design study of AlGaAs/GaAs HBTs

IEEE Transactions on Electron Devices, 1990

The frequency performance of AlGaAs/GaAs heterojunction bipolar transistors (HBTs) having different layouts, doping profiles, and layer thicknesses was assessed using the BIPOLE computer program. The optimized design of HBTs was studied, and the high current performances of HBTs and polysilicon emitter transistors were compared. It is shown that no current crowding effect occurs at current densities less than 1×105 A/cm2 for the HBT with emitter stripe width SE<3 μm, and the HBT current-handling capability determined by the peak current-gain cutoff frequency is more than twice as large as that of the polysilicon emitter transistor. An optimized maximum oscillation frequency formula has been obtained for a typical process n-p-n AlGaAs/GaAs HBT having base doping of 1×10 19 cm-3

Large-signal Modeling of SiGe HBT for PA Applications

Accurate modeling of large-signal behavior of power amplifiers (PAs) is key in minimizing the number of design spins and design cycle time. This paper presents the 1-and 2-tone large-signal behavior of SiGe HBT with respect to power, frequency, bias, and transistor geometry. While the transistor's weak nonlinearity is largely determined by the trans-conductance (Gm) and the quasi-static (QS) charge-storage of the transistor, its high-power large-signal behavior heavily depends on the high-current gain roll-off characteristics and supply clamping. It is discussed from a PA-design standpoint how the SiGe bandgap engineering impacts the large-signal behavior through a steeper gain compression at high currents and high power levels. It is also shown that the 2-tone inter-modulation products of a transistor are closely related to its 1-tone distortion characteristics. Finally an accurate prediction of critical parameters of a practical WCDMA PA was demonstrated with careful accounting of the high-current effects in the SiGe HBT transistor.

A user compiled large signal model for GaAs heterojunction bipolar transistors

This paper presents a nonlinear circuit simulation model for III-V Heterojunction Bipolar Transistors (HBTs), implemented using C code in the Agilent ADS circuit simulator as a User Compiled Model (UCM). The UCM is based-on a recently developed compact large-signal model, which includes all physical effects taking place in power III-V based HBT devices. The validity and the accuracy of the UCM are assessed by comparing its simulation results to both measurements and Symbolically Define Device (SDD) simulations in DC, multibias small-signal S-parameters and large-signal microwave power characteristics for a 2x20 m 2 emitter area InGaP/GaAs transistor.

Comparison of a New Modified Gummel-Poon Model and VBIC for AlGaAs/GaAs HBTs

A new modified Gummel-Poon (MGP) based model has been developed and tested on heterojunction bipolar transistors (HBTs). This paper focuses on the comparison of the new MGP and the VBIC models under DC and small-signal operations. The DC parameters of the two models are extracted from Gummel forward and reverse measurements at various junction temperatures and Ic-Vce measurements. The small-signal intrinsic elements are extracted from multi-bias sparameter measurements. DC comparisons between the two model predictions and measurements reveal that the new MGP model surpasses the VBIC DC performances. The sparameter comparisons of simulated and measurements at various bias points, from 1Ghz to 30Ghz, show that the two models are equivalent.

The effects of C/sub bc/ on the linearity of AlGaAs/GaAs power HBTs

IEEE Transactions on Microwave Theory and Techniques, 2001

It is well known that is the dominant nonlinear element in heterojunction bipolar transistors (HBTs). To study its behavior, an analytical nonlinear HBT equivalent-circuit model has been developed. The present model includes the effect of the ionized donor charge in the depleted collector region compensated by the injected mobile charge. The model-based simulation shows that, at a small-signal range, the third-order intermodulation (IM3) of the normal HBT has the normal 3 : 1 gain slope generated by the nonlinearity of. At a large-signal level, the load line passes through some regions with constant because its collector is fully depleted by the injected free carriers, and the growth rate of the IM3 is decreased. The punch-through collector HBT has constant during the whole RF cycle, and the IM3, which is generated by nonlinearity, has the normal 3 : 1 gain slope for the all input signal level. Therefore, the IM3 level is significantly lower for the punch-through HBT at a low-power level, but the IM3s of both devices are comparable at a high-power level. The experiment supports our proposed model.

Analysis of the surface base current drift in GaAs HBT's

Microelectronics Reliability, 1996

A field-induced degradation mechanism responsible for the surface base current drift in GaAs HBT's is studied on the basis of accelerated life-tests : two stress conditions are applied to HBT's and associated TLM structures. An EDX analysis performed on the base ohmic contact confirms the migration of metallic species which are assessed to spread into the extrinsic base region of AIGaAs/GaAs HBT's. The self-passivated GalnP/GaAs technology is expected to improve the HBT reliability.