Understanding the Threshold Voltage Instability During OFF-State Stress in p-GaN HEMTs

Efthymiou, Loizos; Murukesan, Karthick; Longobardi, Giorgia; Udrea, F.; Shibib, Ayman; Terrill, K.W.

doi:10.1109/led.2019.2925776

Cited by 88 publications

(32 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It is also worth to mention that the shift can be affected by the self-heating of the device during the stress. A positive VTH shift under negative gate bias was also reported in [19,35].…”

Section: B Negative Gate Stresssupporting

confidence: 60%

“…Commercially available GaN HEMTs have been the subject of different studies including electrothermal characterization [5][6][7]and reliability studies (summarized in [8]), with a JEDEC committee (JC-70) focused on the development of standards for GaN power devices [9,10]. The reliability studies include power cycling [11][12][13], dynamic ON-state resistance [14][15][16] and threshold voltage (VTH) instability [17][18][19][20][21][22][23], which is the focus of the investigations presented in this paper.…”

Section: Introductionmentioning

confidence: 99%

“…The previous studies [17][18][19][20][21][22][23] highlight the complexity of the gate stack structure and different threshold voltage shifts depending on the magnitude of the gate stress voltage. For example, in Schottky gate GaN devices, positive VTH drift at low gate voltage VGS bias has been reported due to electron trapping in acceptor like states at the AlGaN/GaN interface [21,24].…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Characterizing Threshold Voltage Shifts and Recovery in Schottky Gate and Ohmic Gate GaN HEMTs

Gonzalez

Etoz

Alatise

2020

2020 IEEE Energy Conversion Congress and Exposition (ECCE)

View full text Add to dashboard Cite

show abstract

“…It is also worth to mention that the shift can be affected by the self-heating of the device during the stress. A positive VTH shift under negative gate bias was also reported in [19,35].…”

Section: B Negative Gate Stresssupporting

confidence: 60%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Characterizing Threshold Voltage Shifts and Recovery in Schottky Gate and Ohmic Gate GaN HEMTs

Gonzalez

Etoz

Alatise

2020

2020 IEEE Energy Conversion Congress and Exposition (ECCE)

View full text Add to dashboard Cite

show abstract

“…Even though the p-GaN demonstrates easy gate control V TH , this method still lacks enough negative gate bias experiment studies to verify the V TH stability and device degradation. Meantime, the p-GaN demonstrated E-mode GaN HEMT device instability behavior induced by the positive gate bias stress and off-state drain bias stress, and under hard switching operations, was well discussed and reported in several studies [21][22][23]. In this paper, we focused on studying the degradation and instability behavior of the device, which was induced by the negative gate bias stress in the form of pulsed and prolonged stress conditions at room temperature.…”

Section: Introductionmentioning

confidence: 96%

Analysis of Instability Behavior and Mechanism of E-Mode GaN Power HEMT with p-GaN Gate under Off-State Gate Bias Stress

2021

View full text Add to dashboard Cite

In this study, we investigate the degradation characteristics of E-mode GaN High Electron Mobility Transistors (HEMTs) with a p-GaN gate by designed pulsed and prolonged negative gate (VGS) bias stress. Device transfer and transconductance, output, and gate-leakage characteristics were studied in detail, before and after each pulsed and prolonged negative VGS bias stress. We found that the gradual degradation of electrical parameters, such as threshold voltage (VTH) shift, on-state resistance (RDS-ON) increase, transconductance max (Gm, max) decrease, and gate leakage current (IGS-Leakage) increase, is caused by negative VGS bias stress time evolution and magnitude of stress voltage. The significance of electron trapping effects was revealed from the VTH shift or instability and other parameter degradation under different stress voltages. The degradation mechanism behind the DC characteristics could be assigned to the formation of hole deficiency at p-GaN region and trapping process at the p-GaN/AlGaN hetero-interface, which induces a change in the electric potential distribution at the gate region. The design and application of E-mode GaN with p-GaN gate power devices still need such a reliability investigation for significant credibility.

show abstract

“…With the case of Mg diffusion into the AlGaN barrier layer and GaN channel layer, Loizos Efthymiou et al discovered that Vth shifts firmly with Mg diffusion [ 19 ]. CL measurements revealed Mg diffusion along the dislocation [ 20 ].…”

Section: Introductionmentioning

confidence: 99%

High Hole Concentration and Diffusion Suppression of Heavily Mg-Doped p-GaN for Application in Enhanced-Mode GaN HEMT

Dai

Thu

et al. 2021

Nanomaterials

View full text Add to dashboard Cite

The effect of Mg doping on the electrical and optical properties of the p-GaN/AlGaN structures on a Si substrate grown by metal organic chemical vapor deposition was investigated. The Hall measurement showed that the activation efficiency of the sample with a 450 sccm Cp2Mg flow rate reached a maximum value of 2.22%. No reversion of the hole concentration was observed due to the existence of stress in the designed sample structures. This is attributed to the higher Mg-to-Ga incorporation rate resulting from the restriction of self-compensation under compressive strain. In addition, by using an AlN interlayer (IL) at the interface of p-GaN/AlGaN, the activation rate can be further improved after the doping concentration reaches saturation, and the diffusion of Mg atoms can also be effectively suppressed. A high hole concentration of about 1.3 × 1018 cm−3 can be achieved in the p-GaN/AlN-IL/AlGaN structure.

show abstract

Understanding the Threshold Voltage Instability During OFF-State Stress in p-GaN HEMTs

Cited by 88 publications

References 14 publications

Characterizing Threshold Voltage Shifts and Recovery in Schottky Gate and Ohmic Gate GaN HEMTs

Characterizing Threshold Voltage Shifts and Recovery in Schottky Gate and Ohmic Gate GaN HEMTs

Analysis of Instability Behavior and Mechanism of E-Mode GaN Power HEMT with p-GaN Gate under Off-State Gate Bias Stress

High Hole Concentration and Diffusion Suppression of Heavily Mg-Doped p-GaN for Application in Enhanced-Mode GaN HEMT

Contact Info

Product

Resources

About