An Accurate Switching Current Measurement Based on Resistive Shunt Applied to Short Circuit GaN HEMT Characterization

The use of a resistive shunt is one of the simplest and most used methods for measuring current in an electronic device. Many researchers use this method to measure drain current during short-circuiting of fast devices such as GaN HEMTs. However, the high switching speed of these devices together with the non-ideality of the shunt resistors produces an overestimation of the current in the initial phases of the transient. In this paper, a passive compensation network is proposed, which is formed by adding an inductor to the voltage measurement circuit and allows an accurate measurement of the current using the resistive shunt even in the presence of very fast devices. The proposed method is validated by simulations and experimental measurements.

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Determination of AlGaN/GaN HEMT Reliability Using Optical Pumping as a Characterization Method

MRS Proceedings ◽

10.1557/opl.2012.1138 ◽

2012 ◽

Vol 1432 ◽

Author(s):

D. Cheney ◽

R. Deist ◽

B. Gila ◽

F. Ren ◽

P. Whiting ◽

...

Keyword(s):

Band Gap ◽

Optical Pumping ◽

Drain Current ◽

Stress Tests ◽

Optically Pumped ◽

Gan Hemt ◽

Load Line ◽

Gan Hemts ◽

Dc Stress

ABSTRACTBy pumping AlGaN/GaN HEMTs with below band-gap light we observe changes in drain current that correspond to the trapping and detrapping of carriers within the band-gap. These changes in drain current are indicators of trap density, since the energy from a specific wavelength of light pumps traps whose activation energies are less than or equal to that of the light source.AlGaN/GaN HEMTs on SiC with dual submicron gates with widths of 125nm, 140nm, or 170nm, are DC-stressed under three different conditions along a load line: VGS=0, VDS=5 (on-state), VGS=-2, VDS=9.2 and, VGS=-6, VDS=25 (off-state). The stress tests are interrupted at 20% degradation and the optically pumped comparisons to the baseline are measured.This paper describes the optical pumping technique and results from experiments of AlGaN/GaN HEMTs under the three DC stress biases along a load line.

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A novel high breakdown voltage and high switching speed GaN HEMT with p-GaN gate and hybrid AlGaN buffer layer for power electronics applications

Chinese Physics B ◽

10.1088/1674-1056/abaee5 ◽

2020 ◽

Vol 29 (12) ◽

pp. 127701

Author(s):

Yong Liu ◽

Qi Yu ◽

Jiang-Feng Du

Keyword(s):

Power Electronics ◽

Buffer Layer ◽

Breakdown Voltage ◽

Switching Speed ◽

Gan Hemt ◽

High Breakdown Voltage ◽

High Switching Speed ◽

Algan Buffer

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An Improved Analytical Model for Crosstalk of SiC MOSFET in a Bridge-Arm Configuration

Energies ◽

10.3390/en14030683 ◽

2021 ◽

Vol 14 (3) ◽

pp. 683

Author(s):

Dakang Yuan ◽

Yiming Zhang ◽

Xuhong Wang

Keyword(s):

Analytical Model ◽

Good Accuracy ◽

Experimental Measurements ◽

Switching Speed ◽

Fast Switching ◽

Proposed Model ◽

Oscillation Process ◽

Simulation And Experiment ◽

High Switching Speed ◽

Voltage Switching

SiC MOSFETs have an excellent characteristic of high switching speed, which can improve the efficiency and power density of converters significantly. However, the fast switching processes of SiC MOSFETs cause serious crosstalk problems in bridge-arm configurations, which restricts the devices’ performances. This paper presents a detailed and accurate improved crosstalk analytical model, which takes into account the nonlinear capacitances, the parasitic inductances, the reverse recovery characteristics of the anti-parallel diodes, and the nonlinear voltage switching and damping oscillation process. The novelty of the proposed model lies in the fact that under the condition of comprehensively considering all these non-ideal factors of the bridge-arm, the effects of multi-parasitic elements and multi-variables coupling to the crosstalk are hierarchically divided. The parasitic elements and their correlations are described in detail and the direct and indirect variables’ impacts are clearly traced. Thus, according to the different variables switching stages, the influence processes of these parasitic elements and variables can be integrated and a complete equivalent analytical model of the crosstalk process can be derived. The simulation and experiment platforms are established and a series of experimental verifications and comparisons prove that the model can replicate experimental measurements of crosstalk with good accuracy and detail.

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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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WIDE-BANDGAP SEMICONDUCTOR DEVICES FOR AUTOMOTIVE APPLICATIONS

International Journal of High Speed Electronics and Systems ◽

10.1142/s012915640700414x ◽

2007 ◽

Vol 17 (01) ◽

pp. 3-9 ◽

Cited By ~ 5

Author(s):

M. Sugimoto ◽

H. Ueda ◽

T. Uesugi ◽

T. kachi

Keyword(s):

High Performance ◽

Drain Current ◽

Wide Bandgap ◽

Hybrid Vehicles ◽

High Current ◽

Automotive Applications ◽

Power Devices ◽

Gan Hemt ◽

Gan Hemts ◽

Current Operation

In this paper, we discuss requirements of power devices for automotive applications, especially hybrid vehicles and the development of GaN power devices at Toyota. We fabricated AlGaN/GaN HEMTs and measured their characteristics. The maximum breakdown voltage was over 600V. The drain current with a gate width of 31mm was over 8A. A thermograph image of the HEMT under high current operation shows the AlGaN/GaN HEMT operated at more than 300°C. And we confirmed the operation of a vertical GaN device. All the results of the GaN HEMTs are really promising to realize high performance and small size inverters for future automobiles.

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ANALYSIS OF LOW FREQUENCY DRAIN CURRENT NOISE IN AlGaN/GaN HEMTS ON Si SUBSTRATE

Fluctuation and Noise Letters ◽

10.1142/s0219477504001926 ◽

2004 ◽

Vol 04 (02) ◽

pp. L319-L328

Author(s):

NATHALIE MALBERT ◽

NATHALIE LABAT ◽

ARNAUD CURUTCHET ◽

ANDRE TOUBOUL ◽

CHRISTOPHE GAQUIÈRE ◽

...

Keyword(s):

Low Frequency ◽

Drain Current ◽

Current Noise ◽

Gate Length ◽

Gate Leakage Current ◽

Si Substrate ◽

Saturation Regime ◽

Gan Hemt ◽

Noise Measurements ◽

Gan Hemts

This paper deals with the analysis of the low frequency drain current noise in gallium nitride FET on silicon substrate. The drain current noise is compared for devices with gate length of 1.5μm and 3.5μm. We discuss two types of noise mechanisms both used as a diagnostic tool: generation-recombination noise and 1/f noise. Measurements in saturation regime have revealed a g-r noise mechanism correlated with the activation of discrete traps. The analysis of the normalized drain current spectral density vs. the normalized gate voltage Vgn=(Vg-Vt)/|Vt| has been studied. In particular, we have pointed out that the evolution of the 1/f noise level strongly depends on the evolution of the gate leakage current. On the basis of the 1/f normalized noise, i.e. the αH/N parameter, GaN HEMT on silicon have demonstrated as low LF noise as GaAs based transistors.

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A Very Robust AlGaN/GaN HEMT Technology to High Forward Gate Bias and Current

Active and Passive Electronic Components ◽

10.1155/2012/493239 ◽

2012 ◽

Vol 2012 ◽

pp. 1-4 ◽

Cited By ~ 3

Author(s):

Bradley D. Christiansen ◽

Eric R. Heller ◽

Ronald A. Coutu ◽

Ramakrishna Vetury ◽

Jeffrey B. Shealy

Keyword(s):

Breakdown Voltage ◽

Threshold Voltage ◽

Drain Current ◽

Conventional Wisdom ◽

Gate Bias ◽

Threshold Voltage Shift ◽

Bias Stress ◽

Gan Hemt ◽

Positive Threshold ◽

Gan Hemts

Reports to date of GaN HEMTs subjected to forward gate bias stress include varied extents of degradation. We report an extremely robust GaN HEMT technology that survived—contrary to conventional wisdom—high forward gate bias (+6 V) and current (>1.8 A/mm) for >17.5 hours exhibiting only a slight change in gate diode characteristic, little decrease in maximum drain current, with only a 0.1 V positive threshold voltage shift, and, remarkably, a persisting breakdown voltage exceeding 200 V.

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