Enhancement of power performance for class e amplifier based on analysis of the transistor drain current oscillogram

ABSTRACTChannel-recessed 4H-SiC MESFETs were fabricated and demonstrated excellent small signal characteristics. A saturated current of 250 − 270 mA/mm at Vgs = 0 V and a maximum transconductance of 40 − 45 mS/mm were measured for channel-recessed devices with a gate length of 0.45 m. The three-terminal breakdown voltages (Vds) range from 120 V to 150 V. The Ft and Fmax of the 2 × 200 m devices were measured to be 14.5 GHz and 40 GHz, respectively. The channel recess technique results in a lower saturation current but higher breakdown voltage which makes it possible for the devices to operate at high voltages. Si3N4 passivation suppresses the instability in DC characteristics and improves CW power performance by reducing the surface effects. Less dispersion in the drain current during a power sweep was observed after passivation.

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RF Power Performance Evaluation of Surface Channel Diamond MESFET

MRS Proceedings ◽

10.1557/proc-1203-j15-04 ◽

2009 ◽

Vol 1203 ◽

Cited By ~ 1

Author(s):

Maria Cristina Rossi ◽

Paolo Calvani ◽

Gennaro Conte ◽

Vittorio Camarchia ◽

Federica Cappelluti ◽

...

Keyword(s):

Output Power ◽

Threshold Voltage ◽

Polycrystalline Diamond ◽

Drain Current ◽

Rf Power ◽

Power Performance ◽

Power Devices ◽

Large Signal ◽

Device Structure ◽

Power Added Efficiency

AbstractLarge-signal radiofrequency performances of surface channel diamond MESFET fabricated on hydrogenated polycrystalline diamond are investigated. The adopted device structure is a typical coplanar two-finger gate layout, characterized in DC by an accumulation-like behavior with threshold voltage Vt ∼ 0-0.5 V and maximum DC drain current of 120 mA/mm. The best radiofrequency performances (in terms of fT and fmax) were obtained close to the threshold voltage. Realized devices are analyzed in standard class A operation, at an operating frequency of 2 GHz. The MESFET devices show a linear power gain of 8 dB and approximately 0.2 Wmm RF output power with 22% power added efficiency. An output power density of about 0.8 W/mm can be then extrapolated at 1 GHz, showing the potential of surface channel MESFET technology on polycrystalline diamond for microwave power devices.

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Study of Effective Graded Oxide Capacitance and Length Variation on Analog, RF and Power Performances of Dual Gate Underlap MOS-HEMT

10.21203/rs.3.rs-212444/v1 ◽

2021 ◽

Author(s):

Sneha Ghosh ◽

Anindita Mondal ◽

Mousiki Kar ◽

Atanu Kundu

Keyword(s):

Dielectric Material ◽

Drain Current ◽

High Electron Mobility Transistor ◽

Oxide Semiconductor ◽

Superior Performance ◽

Length Variation ◽

High Electron ◽

Power Performance ◽

Output Resistance ◽

Transistor Mos

Abstract Comparative analysis of a Symmetric Heterojunction Underlap Double Gate (U-DG) GaN/AlGaN Metal Oxide Semiconductor High Electron Mobility Transistor (MOS-HEMT) on varying the effective capacitance by using different oxide materials on source and drain sides, and determination of optimum length of oxides for the superior device performance has been presented in this work. This paper shows a detailed performance analysis of the Analog Figure of Merits (FoMs) like variation of Drain Current (IDS), Transconductance (gm), Output Resistance (R0), Intrinsic Gain (gmR0), RF FoMs like cut-off frequency (fT), maximum frequency of oscillation (fMAX), gate to source resistance (RGS), gate to drain resistance (RGD), gate to drain capacitance(CGD), gate to source capacitance (CGS) and total gate capacitance (CGG) using Non-Quasi-Static (NQS) approach. Power analysis includes Output power (Pout), Gain in dBm and power output efficiency (POE) have been studied. Studies reveal that the device with higher dielectric material towards source side shows superior performance. On subsequently changing the proportion of two oxides in a layer by varying length, it is observed that as the proportion of oxide increases the device demonstrates more desirable Analog and RF characteristics while best power performance is obtained from device with equal lengths of HfO2 and SiO2.

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AlGaN/GaN epitaxy and technology

International Journal of Microwave and Wireless Technologies ◽

10.1017/s175907871000005x ◽

2010 ◽

Vol 2 (1) ◽

pp. 3-11 ◽

Cited By ~ 21

Author(s):

Patrick Waltereit ◽

Wolfgang Bronner ◽

Rüdiger Quay ◽

Michael Dammann ◽

Rudolf Kiefer ◽

...

Keyword(s):

Output Power ◽

Supply Voltage ◽

Drain Current ◽

High Electron Mobility Transistors ◽

Base Station ◽

High Electron ◽

Power Performance ◽

Power Added Efficiency ◽

Electron Mobility Transistors ◽

Conversion Efficiencies

We present an overview on epitaxial growth, processing technology, device performance, and reliability of our GaN high electron mobility transistors (HEMTs) manufactured on 3- and 4-in. SiC substrates. Epitaxy and processing are optimized for both performance and reliability. We use three different gate lengths, namely 500 nm for 1–6 GHz applications, 250 nm for devices between 6 and 18 GHz, and 150 nm for higher frequencies. The developed HEMTs demonstrate excellent high-voltage stability, high power performance, and large DC to RF conversion efficiencies for all gate lengths. On large gate width devices for base station applications, an output power beyond 125 W is achieved with a power added efficiency around 60% and a linear gain around 16 dB. Reliability is tested both under DC and RF conditions with supply voltage of 50 and 30 V for 500 and 250 nm gates, respectively. DC tests on HEMT devices return a drain current change of just about 10% under IDQ conditions. Under RF stress the observed change in output power density is below 0.2 dB after more than 1000 h for both gate length technologies.

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Correlation of Drain Current Pulsed Response with Microwave Power Output in AlGaN/GaN HEMTs

MRS Proceedings ◽

10.1557/proc-572-541 ◽

1999 ◽

Vol 572 ◽

Cited By ~ 9

Author(s):

S. C. Binari ◽

K. Ikossi-Anastasiou ◽

W. Kruppa ◽

H. B. Dietrich ◽

G. Kelner ◽

...

Keyword(s):

Power Output ◽

Microwave Power ◽

Drain Current ◽

Current Response ◽

Small Signal ◽

Power Performance ◽

Device Structure ◽

Gan Hemt ◽

Signal Characteristics ◽

Power Densities

ABSTRACTThe drain-current response to short (<1μs) gate pulses has been measured for a series of GaN HEMT wafers that have similar dc and small-signal characteristics. This response has been found to correlate well with the measured microwave power output. For example, for devices where the pulsed drain current is greater than 70% of the dc value, output power densities of up to 2.3 W/mm are attained. This is in contrast with 0.5 W/mm measured for devices with low pulse response (less than 20% of the dc value). These results, which can be explained by the presence of traps in the device structure, provide a convenient test which is predictive of power performance.

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The Effects of Limited Drain Current and On Resistance on the Performance of an LDMOS Inverse Class-E Power Amplifier

IEEE Transactions on Microwave Theory and Techniques ◽

10.1109/tmtt.2008.2011175 ◽

2009 ◽

Vol 57 (2) ◽

pp. 336-343 ◽

Cited By ~ 10

Author(s):

Fei You ◽

Songbai He ◽

Xiaohong Tang ◽

Xiangke Deng

Keyword(s):

Power Amplifier ◽

Drain Current ◽

Class E

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High Efficiency AlN/GaN HEMTs for Q-Band Applications with an Improved Thermal Dissipation

International Journal of High Speed Electronics and Systems ◽

10.1142/s0129156419400032 ◽

2019 ◽

Vol 28 (01n02) ◽

pp. 1940003 ◽

Cited By ~ 2

Author(s):

Riad Kabouche ◽

Romain Pecheux ◽

Kathia Harrouche ◽

Etienne Okada ◽

Farid Medjdoub ◽

...

Keyword(s):

High Efficiency ◽

Drain Current ◽

High Electron Mobility Transistors ◽

Thermal Dissipation ◽

High Electron ◽

Power Performance ◽

Power Added Efficiency ◽

Carbon Doped ◽

Electron Mobility Transistors ◽

Band Power

In this paper, we demonstrate Q-band power performance of carbon doped AlN/GaN high electron mobility transistors (HEMTs) using a deep sub-micrometer gate length (120 nm). With a maximum drain current density ID of 1.5 A/mm associated to a high electron confinement and an extrinsic transconductance gm of 500 mS/mm, this structure shows excellent electrical characteristics. A maximum oscillation frequency fmax of 242 GHz has been observed. As a result, a state-of-the-art combination at 40 GHz of output power density (POUT = 7 W/mm) and power added efficiency (PAE) of 52% up to VDS = 25V has been obtained. The achievement of such outstanding performance is attributed to the reduced thermal resistance (RTH) as compared to the commonly used double heterostructure by means of Raman thermography.

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