Characterization of thermal and frequency-dispersion effects in GaAs MESFET devices

2013 IEEE MTT-S International Microwave Symposium Digest (MTT)

Avolio

et al. 2013

In this paper an identification procedure for an FET analytical model oriented to µm- and mm-wave applications is presented. It is based on low-frequency large-signal measurements to determine with a high level of accuracy the nonlinear current source parameters. In addition, vector intermodulation measurements are used for the identification of the strictly nonlinear dynamic effects of the intrinsic device. As case study, the identification technique is applied to a 0.15-µm GaAs pHEMT. The extracted model is validated through comparison with nonlinear measurements carried out under conditions different from the ones used for model identification. A very good agreement with measurements has been achieved, despite the small number of data used to determine the model parameters

Section: Identification Proceduresmentioning

confidence: 99%

Microwave FET model identification based on vector intermodulation measurements

Bosi

2013 IEEE MTT-S International Microwave Symposium Digest (MTT)

Avolio

et al. 2013

“…A pulsed I/V measurement system is based on the application of short voltage pulses (both positive and negative) superimposed on given dc levels [1]- [2]. The system thus allows to dynamically reach any point in the I\V plane starting from an arbitrary dc bias condition.…”

Section: Introductionmentioning

confidence: 99%

A new empirical model for the characterization of low-frequency dispersive effects in FET electron devices accounting for thermal influence on the trapping state

2008 IEEE MTT-S International Microwave Symposium Digest

Vadalà

Vannini

et al. 2008

It is well known that low-frequency dispersive effects cause important deviations between static (dc) and dynamic electron device current\voltage (I\V) characteristics, which must be accurately accounted for in nonlinear device models for microwave circuit design. As a matter of fact, a very high level of accuracy has been obtained by exploiting modeling approaches based on bias-dependent model parameters (e.g. stored into look-up tables). However, experimental characterization of these parameters is usually limited by the device safe operating area. Moreover, their practical use can be limited in the circuit design phase due to simulation time and memory occupation problems. On the other hand, too much simple models based on easy-to-compute analytical expressions do not satisfy the accuracy requirements usually needed for firstrun-success MMIC design. In this paper, a new analytical model for the characterization of low-frequency dispersive effects is presented, whose aim is essentially related to the request of very accurate prediction capabilities yet preserving the numerical efficiency.

“…By substituting (15) in (14), the following relationship between the two functions and is found: (16) or, equivalently,…”

Section: B Link Between Andmentioning

confidence: 99%

Accurate pHEMT nonlinear modeling in the presence of low-frequency dispersive effects

IEEE Trans. Microwave Theory Techn.

Santarelli

Traverso

et al. 2005

Abstract-Low-frequency (LF) dispersive phenomena due to device self-heating and/or the presence of "traps" (i.e., surface state densities and bulk spurious energy levels) must be taken into account in the large-signal dynamic modeling of III-V field-effect transistors when accurate performance predictions are pursued, since these effects cause important deviations between direct current (dc) and dynamic drain current characteristics. In this paper, a new model for the accurate characterization of these phenomena above their cutoff frequencies is presented, which is able to fully exploit, in the identification phase, large-signal current-voltage ( -) measurements carried out under quasi-sinusoidal regime using a recently proposed setup.