| 1. |
- Avolio, G., et al.
(författare)
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Millimeter-Wave FET Nonlinear Modelling Based on the Dynamic-Bias Measurement Technique
- 2014
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Ingår i: IEEE Transactions on Microwave Theory and Techniques. - : Institute of Electrical and Electronics Engineers (IEEE). - 0018-9480 .- 1557-9670. ; 62:11, s. 2526-2537
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Tidskriftsartikel (refereegranskat)abstract
- In the paper, the nonlinear model of a microwave transistor is extracted from large-signal measurements acquired under "dynamic-bias" operation. Specifically, the transistor is driven by low-frequency large signals while a high-frequency tickle is applied on top of them. The low-frequency large signals, along with the dc bias voltages, set the large-signal operating point which represents a dynamic-bias condition for the device under test. Thanks to this technique, one can get at once and separately the nonlinear currents and charges of the transistor as a result of a very few nonlinear measurements. Additionally, the proposed technique allows one to accurately reconstruct the time-domain waveforms at the device-under-test terminals while the frequency of the tickle can be set as high as the bandwidth of today's vector calibrated nonlinear measurement systems (i.e., 67 GHz). The approach, which is general and independent of device technology, is applied on a 0.15-mu m GaAs pHEMT specifically designed for resistive cold-FET mixer applications.
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| 2. |
- Avolio, G., et al.
(författare)
-
Nonlinear model for 40-GHz cold-FET operation
- 2014
-
Ingår i: International Workshop on Integrated Nonlinear Microwave and Millimetre-Wave Circuits, INMMiC 2014.
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Konferensbidrag (refereegranskat)abstract
- We extract the nonlinear model of a 0.15 μm GaAs pHEMT for cold-FET mixer applications. The model parameters are extracted from experimental data obtained by simultaneously driving the device under test with low-frequency large signals and a tickle tone at the RF operating frequency. The advantage of this approach is twofold. Firstly, as a result of a single measurement one can get separately the nonlinear currents and charge. Secondly, one can perform nonlinear characterization, and subsequently modeling, even if the RF frequency is such that its harmonics cannot be measured by today's nonlinear network vector analyzers.
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| 3. |
- Avolio, G., et al.
(författare)
-
Small-Versus Large-Signal Extraction of Charge Models of Microwave FETs
- 2014
-
Ingår i: IEEE Microwave and Wireless Components Letters. - : Institute of Electrical and Electronics Engineers (IEEE). - 1558-1764 .- 1531-1309. ; 24:6, s. 394-396
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Tidskriftsartikel (refereegranskat)abstract
- In this letter we extract the parameters of the charge equations of a microwave transistor nonlinear model which is available in commercial CAD tools. In particular, the charge model parameters are extracted starting from small- and large-signal measurements. A better accuracy can be achieved when using large-signal measurements since the model parameters are obtained from experimental data which better reproduce the actual operating condition of the device under test. An advanced 0.15 x 300 mu m(2) pHEMT in GaAs technology, aimed at cold-FET mixer design, is considered as case study.
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| 4. |
- Crupi, G., et al.
(författare)
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Purely analytical extraction of an improved nonlinear FinFET model including non-quasi-static effects
- 2009
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Ingår i: Microelectronic Engineering. - : Elsevier BV. - 0167-9317. ; 86:11, s. 2283-2289
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Tidskriftsartikel (refereegranskat)abstract
- An analytical procedure is proposed for extracting a new nonlinear FinFET model, which accounts for non-quasi static effects. The accuracy and the robustness of the obtained nonlinear model are completely validated through the comparison between simulated and measured device behaviour in both linear and nonlinear cases. This study clearly shows that the inclusion of the non-quasi-static phenomena leads to significant model simulation improvements, which become more pronounced at higher frequency. (C) 2009 Elsevier B.V. All rights reserved.
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| 5. |
- Crupi, G., et al.
(författare)
-
Analysis of quasi-static assumption in nonlinear finFET model
- 2008
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Ingår i: 2008 17th International Conference on Microwaves, Radar and Wireless Communications, MIKON 2008. - 9788390666280
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Konferensbidrag (refereegranskat)abstract
- The construction and validation of a quasi-static nonlinear microwave model for FinFETs are investigated. A very good agreement between model simulations and measurements is obtained under different DC bias points, input power levels, fundamental frequencies up to 5 GHz, and device geometries. Since the intrinsic part of the FET model is based on the quasi-static approximation, the goal of this work is to analyze in detail the limitations of this assumption by examining the intrinsic admittance parameters versus the frequency.
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| 6. |
- Crupi, G., et al.
(författare)
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Combined empirical and look-up table approach for non-quasi-static modelling of GaN HEMTs
- 2009
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Ingår i: 9th International Conference on Telecommunications in Modern Satellite, Cable, and Broadcasting Services, TELSIKS 2009 - Proceedings of Paper. - 9781424443833 ; , s. 40-43
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Konferensbidrag (refereegranskat)abstract
- In this paper the empirical and the look-up table approaches are combined to accurately model a gallium nitride based HEMT on silicon carbide. That solution allows to exploit the advantages of both approaches. The validity of the extracted model is verified by comparing model simulations with DC and microwave measurements.
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| 7. |
- Crupi, G., et al.
(författare)
-
Non-linear FinFET Modeling: Lookup Table and Empirical Approaches
- 2008
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Ingår i: International Journal of Microwave and Optical Technology. - 1553-0396. ; 3:3, s. 157-164
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Tidskriftsartikel (refereegranskat)abstract
- The non-linear microwave modeling of advanced transistors is becoming more and more essential to the design and fabrication processes. Consequently, this study is focused on the equivalent circuit based non-linear microwave modeling of FinFET. An accurate multi-bias small signal equivalent circuit is extracted and subsequently used for analytically constructing a non-linear full blown lookup table model. Furthermore, an alternative model implementation, which is based on empirical expressions, is investigated. The validity of both non-linear modeling approaches is confirmed by the good agreement between model simulations and large signal measurements.
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