AlGaN/GaN Recessed MIS-Gate HFET With High-Threshold-Voltage Normally-Off Operation for Power Electronics Applications

Oka, Tohru; Nozawa, T.

doi:10.1109/led.2008.2000607

Cited by 362 publications

(184 citation statements)

References 23 publications

Supporting

Mentioning

168

Contrasting

Order By: Relevance

“…Afterwards the wafers were passivated with a 100 nm thick SiNx layer. The gate trench in the passivation was defined using optical lithography and with a low-bias SF 6 ICP dry etching process, followed by the additional CF 4 or Ar plasma treatment of the AlGaN surface. The parameters for this treatment were optimized by Hallmeasurements on test samples.…”

Section: Experimental Details 21 Device Fabricationmentioning

confidence: 99%

“…For safety reasons, normally-off (enhancement mode) devices are required but AlGaN/GaN HEMTs are intrinsically normally-on (depletion mode). Several approaches have been proposed to realize normally-off GaN transistors like gate-recess [2], p-doped AlGaN gate [3] and recessed MISFET [4]. Furthermore Cai et al [5] showed enhancement mode AlGaN/GaN HEMTs using a CF 4 plasma treatment in the gate region before metallization resulting in a threshold voltage of +0.9 V. Cai et al argues that this additional fluorine based plasma treatment incorporates fluorine ions into the AlGaN barrier beneath the gate.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Electrical and EDX‐analysis of CF₄ and Ar plasma treated AlGaN/GaN HEMTs

Kotara

Hilt

Kirmse

et al. 2011

Phys. Status Solidi C

View full text Add to dashboard Cite

In this paper we have investigated the effect of CF4 plasma treatment on AlGaN/GaN HEMTs and compared it with Ar plasma treated devices. We have investigated the electrical characteristics of the devices using transistor characteristics as wells as CV measurements in order to verify the impacts of the different treatments on the electron concentration in the 2DEG. Furthermore, a TEM‐EDX analysis was performed to find out if any fluorine incorporation in the AlGaN barrier during the CF4 plasma treatment occurs. No significant impact of the fluorine on the threshold voltage could be determined, We conclude that fluorine incorporation is not responsible for the threshold voltage shift. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

show abstract

Section: Experimental Details 21 Device Fabricationmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Electrical and EDX‐analysis of CF₄ and Ar plasma treated AlGaN/GaN HEMTs

Kotara

Hilt

Kirmse

et al. 2011

Phys. Status Solidi C

View full text Add to dashboard Cite

show abstract

“…The dry etching process is commonly used for thinning the AlGaN layer because the wet etching process is not applicable due to the chemical stability of group-III nitrides. [8][9][10] However, dry-etched surfaces are generally negatively affected by various types of damages, which may lead to degradation of the device's performance. 11,12 Moreover, unintentional variations in the recess depth make it difficult to precisely control the threshold voltage (V th ).…”

Section: Introductionmentioning

confidence: 99%

Precise thickness control in recess etching of AlGaN/GaN hetero-structure using photocarrier-regulated electrochemical process

Kumazaki

Uemura

Sato

et al. 2017

Journal of Applied Physics

View full text Add to dashboard Cite

The photocarrier-regulated electrochemical (PREC) process was developed for fabricating recessed-gate AlGaN/GaN high-electron-mobility transistors (HEMTs) for normally off operation. The PREC process is based on photo-assisted electrochemical etching using low-energy chemical reactions. The fundamental photo-electrochemical measurements on AlGaN/GaN heterostructures revealed that the photo-carriers generated in the top AlGaN layer caused homogeneous etching of AlGaN with a smooth surface, but those generated in the GaN layer underneath caused inhomogeneous etching that roughens the surface. The concept of the PREC process is to supply the photo-carriers generated only in the AlGaN layer by selecting proper conditions on light wavelength and voltage. The phenomenon of self-termination etching has been observed during the PREC process, where the etching depth was controlled by light intensity. The recessed-gate AlGaN/GaN HEMT fabricated with the PREC process showed positive threshold voltage and improvement in transconductance compared to planar-gate AlGaN/GaN HEMTs.

show abstract

“…Normally-off HFETs with metal-insulator-semiconductor (MIS) gate structure showing low threshold voltage have been already reported by several groups. [4][5][6] In case of p-GaN gate, the V th can be increased by inserting a thin insulator between the p-GaN gate and the electrode. This structure has MIS gate.…”

Section: Introductionmentioning

confidence: 99%

Threshold voltage control using SiN_x in normally off AlGaN/GaN HFET with p‐GaN gate

Sugiyama

Iida

Iwaya

et al. 2010

Phys. Status Solidi (c)

View full text Add to dashboard Cite

The threshold voltage (Vth) of normally off‐mode AlGaN/GaN junction heterostructure field‐effect transistors with a p‐type GaN gate can be successfully controlled by inserting a SiNx insulator between the p‐GaN and a Ni/Au electrode. The Vth can be controlled from +1 V to above +8 V. Moreover, the gate leakage current of transistors decreases and their gate voltage at which gate current steeply increases becomes higher. The mechanism of the threshold voltage change is analyzed by the equivalent circuit model. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

show abstract

AlGaN/GaN Recessed MIS-Gate HFET With High-Threshold-Voltage Normally-Off Operation for Power Electronics Applications

Cited by 362 publications

References 23 publications

Electrical and EDX‐analysis of CF₄ and Ar plasma treated AlGaN/GaN HEMTs

Electrical and EDX‐analysis of CF₄ and Ar plasma treated AlGaN/GaN HEMTs

Precise thickness control in recess etching of AlGaN/GaN hetero-structure using photocarrier-regulated electrochemical process

Threshold voltage control using SiN_x in normally off AlGaN/GaN HFET with p‐GaN gate

Contact Info

Product

Resources

About

AlGaN/GaN Recessed MIS-Gate HFET With High-Threshold-Voltage Normally-Off Operation for Power Electronics Applications

Cited by 362 publications

References 23 publications

Electrical and EDX‐analysis of CF4 and Ar plasma treated AlGaN/GaN HEMTs

Electrical and EDX‐analysis of CF4 and Ar plasma treated AlGaN/GaN HEMTs

Precise thickness control in recess etching of AlGaN/GaN hetero-structure using photocarrier-regulated electrochemical process

Threshold voltage control using SiNx in normally off AlGaN/GaN HFET with p‐GaN gate

Contact Info

Product

Resources

About

Electrical and EDX‐analysis of CF₄ and Ar plasma treated AlGaN/GaN HEMTs

Electrical and EDX‐analysis of CF₄ and Ar plasma treated AlGaN/GaN HEMTs

Threshold voltage control using SiN_x in normally off AlGaN/GaN HFET with p‐GaN gate