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Microwave Power Devices and Amplifiers for Radars and Communication Systems
Linköping University, Department of Physics, Chemistry and Biology, Semiconductor Materials. Linköping University, The Institute of Technology. (Semiconductor Physics)
2009 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

SiC MESFETs and GaN HEMTs posses an enormous potential in power amplifiers at microwave frequencies due to their wide bandgap features of high electric field strength, high electron saturation velocity and high operating temperature. The high power density combined with the comparably high impedance attainable by these devices also offers new possibilities for wideband power microwave systems. Similarly Si-LDMOS being low cost and lonely silicon based RF power transistor has great contributions especially in the communication sector.

The focus of this thesis work is both device study and their application in different classes of power amplifiers. In the first part of our research work, we studied the performance of transistors in device simulation using physical transistor structure in Technology Computer Aided Design (TCAD). A comparison between the physical simulations and measured device characteristics has been carried out.  We optimized GaN HEMT, Si-LDMOS and enhanced version of our previously fabricated and tested SiC MESFET transistor for enhanced RF and DC characteristics. For large signal AC performance we further extended the computational load pull (CLP) simulation technique to study the switching response of the power transistors. The beauty of our techniques is that, we need no lumped or distributive matching networks to study active device behavior in almost all major classes of power amplifiers. Using these techniques, we studied class A, AB, pulse input class-C and class-F switching response of SiC MESFET. We obtained maximum PAE of 78.3 % with power density of 2.5 W/mm for class C and 84 % for class F power amplifier at 500 MHz. The Si-LDMOS has a vital role and is a strong competitor to wideband gap semiconductor technology in communication sector. We also studied Si-LDMOS (transistor structure provided by Infineon Technologies at Kista, Stockholm) for improved DC and RF performance. The interface charges between the oxide and RESURF region are used not only to improve DC drain current and RF power, gain & efficiency but also enhance its operating frequency up to 4 GHz.

In the second part of our research work, six single stage (using single transistor) power amplifiers have been designed, fabricated and characterized in three phases for applications in communications, Phased Array Radars and EW systems. In the first phase, two class AB power amplifiers are designed and fabricated. The first PA (26 W) is designed and fabricated at 200-500 MHz using SiC MESFET. Typical results for this PA at 60 V drain bias at 500 MHz are, 24.9 dB of power gain, 44.15 dBm output power (26 W) and 66 % PAE. The second PA is designed at 30-100 MHz using SiC MESFET. At 60 V drain bias Pmax is 46.7 dBm (~47 W) with a power gain of 21 dB.

In the second phase, for performance comparison, three broadband class AB power amplifiers are designed and fabricated at 0.7-1.8 GHz using SiC MESFET and two different GaN HEMT technologies (GaN HEMT on SiC and GaN HEMT on Silicon substrate). The measured maximum output power for the SiC MESFET amplifier at a drain bias of Vd= 66 V at 700 MHz the Pmax was 42.2 dBm (~16.6 W) with a PAE of 34.4 %. The results for GaN HEMT on SiC amplifier are; maximum output power at Vd = 48 V is 40 dBm (~10 W), with a PAE of 34 % and a power gain above 10 dB. The maximum output power for GaN HEMT on Si amplifier is 42.5 dBm (~18 W) with a maximum PAE of 39 % and a gain of 19.5 dB.

In the third phase, a high power single stage class E power amplifier is implemented with lumped elements at 0.89-1.02 GHz using Silicon GaN HEMT as an active device. The maximum drain efficiency (DE) and PAE of 67 and 65 % respectively is obtained with a maximum output power of 42.2 dBm (~ 17 W) and a maximum power gain of 15 dB.

Place, publisher, year, edition, pages
Linköping: Linköping University Electronic Press , 2009. , 66 p.
Series
Linköping Studies in Science and Technology. Dissertations, ISSN 0345-7524 ; 1265
National Category
Condensed Matter Physics
Identifiers
URN: urn:nbn:se:liu:diva-19267ISBN: 9789173935760 (print)OAI: oai:DiVA.org:liu-19267DiVA: diva2:232328
Public defence
2009-09-11, BL32 (Nobel), B-huset, Campus Valla, Linköpings universitet, Linkoping, 10:15 (English)
Opponent
Supervisors
Available from: 2009-09-24 Created: 2009-08-21 Last updated: 2017-12-13Bibliographically approved
List of papers
1. Pulse Input Class-C Power Amplifier Response of SiC MESFET using Physical Transistor Structure in TCAD
Open this publication in new window or tab >>Pulse Input Class-C Power Amplifier Response of SiC MESFET using Physical Transistor Structure in TCAD
2008 (English)In: Solid-State Electronics, ISSN 0038-1101, Vol. 52, no 5, 740-744 p.Article in journal (Refereed) Published
Abstract [en]

The switching behavior of a previously fabricated and tested SiC transistor is studied in Class-C amplifier in TCAD simulation. The transistor is simulated for pulse input signals in Class-C power amplifier. The simulated gain (dB), power density (W/mm) and power added efficiency (PAE%) at 500 MHz, 1, 2 and 3 GHz was studied using computational TCAD load pull simulation technique. A Maximum PAE of 77.8% at 500 MHz with 45.4 dB power gain and power density of 2.43 W/mm is achieved. This technique allows the prediction of switching response of the device for switching amplifier Classes (Class-C–F) before undertaking an expensive and time consuming device fabrication. The beauty of this technique is that, we need no matching and other lumped element networks for studying the large signal behavior of RF and microwave transistors.

Keyword
Pulse, Class-C, Power amplifier, New technique, Silicon carbide, MESFET
National Category
Natural Sciences
Identifiers
urn:nbn:se:liu:diva-13285 (URN)10.1016/j.sse.2007.09.022 (DOI)
Available from: 2008-05-13 Created: 2008-05-13 Last updated: 2009-09-24Bibliographically approved
2. High Power, High Efficiency SiC Power Amplifier for Phased ArrayRadar and VHF Applications
Open this publication in new window or tab >>High Power, High Efficiency SiC Power Amplifier for Phased ArrayRadar and VHF Applications
(English)Manuscript (preprint) (Other academic)
Abstract [en]

Wide band gap semiconductor (SiC & GaN) based power amplifiers offer severalsystem critical advantages such as less current leakage, better stability at high temperatureand easier impedance matching. This paper describes the design and fabrication of a singlestageclass-AB power amplifier for 30 to 100 MHz using SiC Schottky gate MetalSemiconductor Field Effect Transistor (MESFET). The maximum output power achieved is46.2 dBm (~42 W) at 50 V DC supply voltage at the drain. The maximum power gain is 21dB and a maximum PAE of 62 %. The amplifier performance was also checked at a higherdrain bias of 60 V at 50 MHz. At this bias voltage the maximum output power was 46.7dBm (~47 W) with a power gain of 21 dB and a maximum PAE of 42.7 %. An averageOIP3 of 54 dBm have been achieved for this amplifier.

Keyword
Power Amplifier, Phased Array Radar, VHF, Silicon Carbide and MESFET.
National Category
Natural Sciences
Identifiers
urn:nbn:se:liu:diva-20862 (URN)
Available from: 2009-09-24 Created: 2009-09-24 Last updated: 2010-01-14Bibliographically approved
3. Single-stage, High Efficiency, 26-Watt power Amplifier using SiC LE-MESFET
Open this publication in new window or tab >>Single-stage, High Efficiency, 26-Watt power Amplifier using SiC LE-MESFET
2006 (English)In: Microwave Conference, 2006. APMC 2006. Asia-Pacific December 12-15, 2006, 441-444 p.Conference paper, Published paper (Refereed)
Abstract [en]

This paper describes a single-stage 26 W negative feedback power amplifier, covering the frequency range 200-500 MHz using a 6 mm gate width SiC lateral epitaxy MESFET. Typical results at 50 V drain bias for the whole band are, around 22 dB power gain, around 43 dBm output power, minimum power added efficiency at P1 dB is 47% at 200 MHz and maximum 60% at 500 MHz and the IMD3 level at 10 dB back-off from P1 dB is below -45 dBc. The results at 60 V drain bias at 500 MHz are, 24.9 dB power gain, 44.15 dBm output power (26 W) and 66% PAE.

Keyword
Schottky gate field effect transistors, feedback, microwave power amplifiers, silicon compounds, SiC, frequency 200 MHz to 500 MHz, lateral epitaxy MESFET, negative feedback, power 26 W, power amplifier, size 6 mm, voltage 50 V
National Category
Engineering and Technology
Identifiers
urn:nbn:se:liu:diva-13283 (URN)10.1109/APMC.2006.4429458 (DOI)
Available from: 2008-05-13 Created: 2008-05-13 Last updated: 2009-09-24Bibliographically approved
4. Broadband Power Amplifier performance of SiC MESFET and CostEffective SiGaN HEMT
Open this publication in new window or tab >>Broadband Power Amplifier performance of SiC MESFET and CostEffective SiGaN HEMT
(English)Manuscript (preprint) (Other academic)
Abstract [en]

This paper describes the broadband power amplifier performance of two differentwide band gap technology transistors at 0.7 to 1.8 GHz using cost effective NitronexGaN HEMT on Silicon (Si) and Cree Silicon Carbide MESFET. The measured resultsfor GaN amplifier are; maximum output power at Vd = 28 V is 42.5 dBm (~18 W), amaximum PAE of 39 % and a maximum gain of 19.5 dB is obtained. The measuredmaximum output power for the SiC amplifier at Vd = 48 V was 41.3 dBm (~13.7 W),with a PAE of 32 % and a power gain above 10 dB. At a drain bias of Vd = 66 V at700 MHz for SiC MESFET amplifier the Pmax was 42.2 dBm (~16.6 W) with a PAE of34.4 %.

Keyword
Broadband, Power Amplifier, GaN HEMT, Silicon Carbide (SiC), MESFET
National Category
Natural Sciences
Identifiers
urn:nbn:se:liu:diva-20863 (URN)
Available from: 2009-09-24 Created: 2009-09-24 Last updated: 2010-01-14Bibliographically approved
5. Designing, Fabrication and Characterization of Power Amplifiers Based on 10-Watt SiC MESFET & GaN HEMT at Microwave Frequencies
Open this publication in new window or tab >>Designing, Fabrication and Characterization of Power Amplifiers Based on 10-Watt SiC MESFET & GaN HEMT at Microwave Frequencies
2008 (English)In: IEEE European Microwave Week, October 10-15, Amsterdam, The Netherlands, 2008, 444-447 p.Conference paper, Published paper (Refereed)
Abstract [en]

This paper describes the design, fabrication and measurement of two single-stage class-AB power amplifiers covering the frequency band from 0.7-1.8 GHz using a SiC MESFET and a GaN HEMT. The measured maximum output power for the SiC amplifier at Vd = 48 V was 41.3 dBm (~13.7 W), with a PAE of 32% and a power gain above 10 dB. At a drain bias of Vd= 66 V at 700 MHz the Pmax was 42.2 dBm (~16.6 W) with a PAE of 34.4%. The measured results for GaN amplifier are; maximum output power at Vd = 48 V is 40 dBm (~10 W), with a PAE of 34% and a power gain above 10 dB. The results for SiC amplifier are better than for GaN amplifier for the same 10-W transistor.

National Category
Natural Sciences
Identifiers
urn:nbn:se:liu:diva-13284 (URN)10.1109/EUMC.2008.4751484 (DOI)
Available from: 2008-05-13 Created: 2008-05-13 Last updated: 2009-09-24Bibliographically approved
6. High Power, Single Stage SiGaN HEMT Class EPower Amplifier at GHz Frequencies
Open this publication in new window or tab >>High Power, Single Stage SiGaN HEMT Class EPower Amplifier at GHz Frequencies
Show others...
(English)Manuscript (preprint) (Other academic)
Abstract [en]

A high power single stage class E power amplifier is implemented with lumped elements at 0.89-1.02GHz using Silicon GaN High Electron Mobility Transistor as an active device. The maximum drain efficiency (DE) and power added efficiency (PAE) of 67 and 65 % respectively is obtained with a maximum output power of 42.2 dBm (~ 17 W) and amaximum power gain of 15 dB. We obtained good results at all measured frequencies.

Keyword
Class E, PAE, Power Amplifiers, Gallium Nitride, HEMT
National Category
Natural Sciences
Identifiers
urn:nbn:se:liu:diva-20864 (URN)
Available from: 2009-09-24 Created: 2009-09-24 Last updated: 2010-04-05Bibliographically approved
7. A New Load Pull TCAD Simulation Technique for Class D, E & FSwitching Characteristics of Transistors
Open this publication in new window or tab >>A New Load Pull TCAD Simulation Technique for Class D, E & FSwitching Characteristics of Transistors
(English)Manuscript (preprint) (Other academic)
Abstract [en]

We have further developed a computational load pull simulation technique inTCAD. It can be used to study the Class-D, E & F switching response of the transistors. Westudied our enhanced version of previously fabricated and tested SiC transistor. Thesimulated Gain (dB), Power density (W/mm), switching loss (W/mm) and power addedefficiency (PAE %) at 500 MHz were studied using this technique. A PAE of 84 % at500MHz with 26 dB Power gain and power density of 2.75 W/mm is achieved. Thistechnique allows the prediction of switching response of the device before undertaking anexpensive and time-consuming device fabrication. The beauty of this technique is that, weneed no matching and other lumped element networks to study the large signal switchingbehavior of RF and microwave transistors.

Keyword
Power Amplifier, Silicon Carbide, TCAD, Switching, Technique
National Category
Natural Sciences
Identifiers
urn:nbn:se:liu:diva-20865 (URN)
Available from: 2009-09-24 Created: 2009-09-24 Last updated: 2010-01-14Bibliographically approved
8. Influence of interface state charges on RF performance of LDMOS transistor
Open this publication in new window or tab >>Influence of interface state charges on RF performance of LDMOS transistor
Show others...
2008 (English)In: Solid-State Electronics, ISSN 0038-1101, E-ISSN 1879-2405, Vol. 52, no 7, 1099-1105 p.Article in journal (Refereed) Published
Abstract [en]

Si-LDMOS transistor is studied by TCAD simulation for improved RF performance. In LDMOS structure, a low-doped reduced surface field (RESURF) region is used to obtain high breakdown voltage, but it reduces the transistor RF performance due to high on-resistance. The interface charges between oxide and the RESURF region are studied and found to have a strong impact on the transistor performance both in DC and RF. The presence of excess interface state charges at the RESURF region results not only higher DC drain current but also improved RF performance in terms of power, gain and efficiency. The most important achievement is the enhancement of operating frequency and RF output power is obtained well above 1 W/mm up to 4 GHz.

Place, publisher, year, edition, pages
Elsevier, 2008
Keyword
Semiconductor devices; Interface state charges; Power electronics; Amplifiers; CAD simulations
National Category
Natural Sciences
Identifiers
urn:nbn:se:liu:diva-20866 (URN)10.1016/j.sse.2008.04.001 (DOI)
Available from: 2009-09-24 Created: 2009-09-24 Last updated: 2017-12-13Bibliographically approved
9. Comparison of Two GaN TransistorsTechnology in Broadband Power Amplifiers
Open this publication in new window or tab >>Comparison of Two GaN TransistorsTechnology in Broadband Power Amplifiers
(English)Manuscript (preprint) (Other academic)
Abstract [en]

This paper compares the performance of two different GaN technology transistors(GaN HEMT on Silicon substrate (PA1) and GaN on SiC PA2) utilized in two broadbandpower amplifiers at 0.7-1.8 GHz. The study explores the broadband power amplifierpotential of both GaN HEMT technologies for Phased Array Radar (PAR) and electronicswarfare (EW) systems. The measured maximum output power for PA1 is 42.5 dBm(~18 W) with a maximum PAE of 39 % and a gain of 19.5 dB. While the measuredmaximum output power for PA2 is 40 dBm with PAE of 35 % and a power gain slightlyabove 10 dB. We obtained high power, gain, wider band width and unconditionalstability without feedback for amplifier based on GaN HEMT technology fabricated on Sisubstrate.

Keyword
Broadband, Power Amplifier, GaN, HEMT and Single-Stage
National Category
Natural Sciences
Identifiers
urn:nbn:se:liu:diva-20867 (URN)
Available from: 2009-09-24 Created: 2009-09-24 Last updated: 2010-01-14Bibliographically approved

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