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

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 Effect of Channel Recess and Passivation on 4H-SiC MESFETs

MRS Proceedings ◽

10.1557/proc-742-k5.19 ◽

2002 ◽

Vol 742 ◽

Cited By ~ 1

Author(s):

Ho-Young Cha ◽

Christopher I. Thomas ◽

Goutam Koley ◽

Lester F. Eastman ◽

Michael G. Spencer

Keyword(s):

Breakdown Voltage ◽

Drain Current ◽

Surface Effects ◽

Gate Length ◽

Small Signal ◽

Saturation Current ◽

Power Performance ◽

Dc Characteristics ◽

Signal Characteristics ◽

Lower Saturation

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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A systematic study of device structure on DC and small‐signal characteristics of millimeter‐wave AlGaN/GaN HEMT

International Journal of Numerical Modelling Electronic Networks Devices and Fields ◽

10.1002/jnm.2623 ◽

2019 ◽

Vol 33 (3) ◽

Cited By ~ 1

Author(s):

Minhan Mi ◽

Xiaohua Ma ◽

Ling Yang ◽

Meng Zhang ◽

Sheng Wu ◽

...

Keyword(s):

Millimeter Wave ◽

Systematic Study ◽

Small Signal ◽

Device Structure ◽

Gan Hemt ◽

Signal Characteristics

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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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Polarization based charge density drain current and small-signal model for nano-scale AlInGaN/AlN/GaN HEMT devices

Superlattices and Microstructures ◽

10.1016/j.spmi.2012.11.020 ◽

2013 ◽

Vol 54 ◽

pp. 188-203 ◽

Cited By ~ 7

Author(s):

D. Godwinraj ◽

Hemant Pardeshi ◽

Sudhansu Kumar Pati ◽

N. Mohankumar ◽

Chandan Kumar Sarkar

Keyword(s):

Charge Density ◽

Drain Current ◽

Small Signal ◽

Signal Model ◽

Gan Hemt ◽

Nano Scale ◽

Small Signal Model

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ABOVE 2 A/mm DRAIN CURRENT DENSITY OF GaN HEMTS GROWN ON SAPPHIRE

International Journal of High Speed Electronics and Systems ◽

10.1142/s012915640700428x ◽

2007 ◽

Vol 17 (01) ◽

pp. 91-95 ◽

Cited By ~ 4

Author(s):

F. Medjdoub ◽

J.-F. Carlin ◽

M. Gonschorek ◽

E. Feltin ◽

M. A. Py ◽

...

Keyword(s):

Current Density ◽

Carrier Density ◽

Drain Current ◽

Small Signal ◽

High Frequencies ◽

Gan Hemt ◽

Sapphire Substrates ◽

Hemt Structure ◽

Gan Hemts ◽

Lattice Matched

We report on the investigation of an InAlN/GaN HEMT structure, delivering higher sheet carrier density than the commonly used AIGaN/GaN system. We achieved in a reproducible way more than 2 A/mm maximum drain current density for a gate length of 0.25 μm with unpassivated undoped devices realized on sapphire substrates. Small signal measurements yield a F T = 31 GHz and F MAX = 52 GHz , which illustrates the capability of these structures to operate at high frequencies. Moreover, the pulsed analysis indicates a more stable surface in the case of AlInN than that of AlGaN , attributed to the lattice matched growth of this barrier with 17% In content on GaN , avoiding strain piezo polarization in the material.

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Highly Scaled Graded Channel GaN HEMT with Peak Drain Current of 2.48 A/mm

AEU - International Journal of Electronics and Communications ◽

10.1016/j.aeue.2021.153774 ◽

2021 ◽

pp. 153774

Author(s):

Husna Hamza K ◽

D. Nirmal ◽

A.S.Augustine Fletcher ◽

L.Arivazhagan ◽

J.Ajayan ◽

...

Keyword(s):

Drain Current ◽

Gan Hemt

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A New Optimization Based Frequency Piecewise Small Signal Model for GaN HEMT

2020 International Conference on Microwave and Millimeter Wave Technology (ICMMT) ◽

10.1109/icmmt49418.2020.9386810 ◽

2020 ◽

Author(s):

Mingqiang Geng ◽

Chao Yu ◽

Jialin Cai

Keyword(s):

Small Signal ◽

Signal Model ◽

Gan Hemt ◽

Small Signal Model

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Physics-Based TCAD Simulation and Calibration of 600 V GaN/AlGaN/GaN Device Characteristics and Analysis of Interface Traps

Micromachines ◽

10.3390/mi12070751 ◽

2021 ◽

Vol 12 (7) ◽

pp. 751

Author(s):

Yu-Lin Song ◽

Manoj Kumar Reddy ◽

Luh-Maan Chang ◽

Gene Sheu

Keyword(s):

Conduction Band ◽

Computer Aided Design ◽

Measurement Data ◽

High Electron Mobility Transistor ◽

High Electron ◽

Device Structure ◽

Gan Hemt ◽

Fixed Charges ◽

Vertical Electric Field ◽

Aided Design

This study proposes an analysis of the physics-based TCAD (Technology Computer-Aided Design) simulation procedure for GaN/AlGaN/GaN HEMT (High Electron Mobility Transistor) device structures grown on Si (111) substrate which is calibrated against measurement data. The presence of traps and activation energies in the device structure will impact the performance of a device, the source of traps and position of traps in the device remains as a complex exercise until today. The key parameters for the precise tuning of threshold voltage (Vth) in GaN transistors are the control of the positive fixed charges −5 × 1012 cm−2, donor-like traps −3 × 1013 cm−2 at the nitride/GaN interfaces, the energy of the donor-like traps 1.42 eV below the conduction band and the acceptor traps activation energy in the AlGaN layer and buffer regions with 0.59 eV below the conduction band. Hence in this paper, the sensitivity of the trap mechanisms in GaN/AlGaN/GaN HEMT transistors, understanding the absolute vertical electric field distribution, electron density and the physical characteristics of the device has been investigated and the results are in good agreement with GaN experimental data.

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