Advantages of the AlGaN spacer in InAlN high-electron-mobility transistors grown using metalorganic vapor phase epitaxy

Yamada, Atsushi; Ishiguro, Tetsuro; Kotani, Junji; Tomabechi, Shuichi; Nakamura, Norikazu; Watanabe, Keiji

doi:10.7567/jjap.55.05fk03

Cited by 6 publications

(9 citation statements)

References 37 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The InAlGaN barrier layer was employed to achieve a low access resistance. To improve surface morphology, the AlGaN spacer was inserted between the 6‐nm‐thick InAlGaN barrier and the GaN channel layer and it is also effective in increasing the electron mobility [7]. A regrown n + ‐GaN layer was used to reduce the ohmic contact resistance, and the ohmic electrodes comprising Ti/Al were formed by a standard evaporation and lift‐off process.…”

Section: Methodsmentioning

confidence: 99%

See 1 more Smart Citation

High‐power‐density InAlGaN/GaN HEMT using InGaN back barrier for W‐band amplifiers

Kotani

Makiyama

Ohki

et al. 2023

Electronics Letters

Self Cite

View full text Add to dashboard Cite

This paper investigated the back‐barrier (BB) effect for gallium nitride (GaN)‐based high‐electron‐mobility transistors with an Fe‐doped buffer and Fe‐buffer + Indium gallium nitride (InGaN)‐BB structure. The authors found that the Fe‐doped buffer + InGaN‐BB structure was effective in reducing the off‐state leakage current compared to the Fe‐doped buffer. Secondary‐ion‐mass spectrometry measurements revealed that the segregated Fe existed with peaks at ∼2 × 1017 cm−3 around the InGaN‐BB layer. The authors believe that the negative charges which are generated by Fe effectively increased the BB effect as they exist just underneath the 2‐dimensional‐electron‐gas channel and successfully achieved a high output power operation of 4.6 W/mm at 94 GHz.

show abstract

Section: Methodsmentioning

confidence: 99%

“…AlGaN barrier and the GaN channel layer and it is also effective in increasing the electron mobility [7]. A regrown n + -GaN layer was used to reduce the ohmic contact resistance, and the ohmic electrodes comprising Ti/Al were formed by a standard evaporation and lift-off process.…”

Section: Fig 2 Measured and Simulated Pinch-off Voltage Depending On ...mentioning

confidence: 99%

High‐power‐density InAlGaN/GaN HEMT using InGaN back barrier for W‐band amplifiers

Kotani

Makiyama

Ohki

et al. 2023

Electronics Letters

Self Cite

View full text Add to dashboard Cite

show abstract

“…The InAlN barrier layer was used, which is appropriate for analyzing the amount of InO x on the surface-oxide because the composition of In was higher than that of the general InAlGaN barrier. [37][38][39][40] In this experiment, the composition of In in InAlN was 17%. The transmission-line-model (TLM) method was used to evaluate electron traps in the surface-oxide before and after light irradiation.…”

Section: Methodsmentioning

confidence: 99%

Surface‐Oxide‐Controlled InAlGaN/GaN High‐Electron‐Mobility Transistors Using Al₂O₃‐Based Insulated‐Gate Structures with H₂O Vapor Pretreatment

Ozaki

Yaita

Yamada

et al. 2022

Physica Status Solidi (a)

Self Cite

View full text Add to dashboard Cite

Herein, Al2O3/InAlGaN/GaN metal–insulator–semiconductor high‐electron‐mobility transistors (MIS‐HEMTs) using H2O vapor pretreatment to decrease the amount of deficient indium oxide (InOx) is successfully developed. InOx acts as an electron trap in the oxide on the surface of the InAlGaN barrier layer. It is clarified that when O2 plasma is used as an oxidant source for atomic‐layer‐deposited (ALD) Al2O3 (O2 plasma‐Al2O3), the forward breakdown voltage increases using the MIS‐HEMT, due to a high density and a low leakage current of O2 plasma‐Al2O3. Furthermore, when using O2 plasma‐Al2O3 for InAlGaN/GaN MIS‐HEMTs, H2O vapor pretreatment is effective in decreasing the amount of InOx and electron traps in the oxide on the surface, thus suppressing current collapse. These results demonstrate the improved output power characteristics of the fabricated Al2O3/InAlGaN/GaN MIS‐HEMT and show the potential of surface‐oxide‐controlled MIS structures as promising process technologies for next‐generation high‐power radio frequency devices.

show abstract

“…For instance, the hexagonal AlxGa1-xN is one of the most promising candidates for ultraviolet (UV)-LED applications, especially because of its wide bandgap (Eg) range from 3.42 eV (for GaN) to 6.2 eV (for AlN) at room temperature 7 . AlxGa1-xN is also an optimum intermediate layer for InGaNbased LEDs and InAlN transistors 2,[8][9][10] . AlxGa1-xN/GaN HEMTs paves the way for achieving high power radio frequency (RF) devices due to high electron mobility, large critical breakdown field, high sheet charge density, high electron saturation velocity, and high temperature operation 11 .…”

Section: Introductionmentioning

confidence: 99%

Strain-stress study of AlxGa1−xN/AlN heterostructures on c-plane sapphire and related optical properties

Feng

Saravade

Chung

et al. 2019

Sci Rep

View full text Add to dashboard Cite

This work presents a systematic study of stress and strain of Al x Ga 1− x N/AlN with composition ranging from GaN to AlN, grown on a c -plane sapphire by metal-organic chemical vapor deposition, using synchrotron radiation high-resolution X-ray diffraction and reciprocal space mapping. The c -plane of the Al x Ga 1− x N epitaxial layers exhibits compressive strain, while the a -plane exhibits tensile strain. The biaxial stress and strain are found to increase with increasing Al composition, although the lattice mismatch between the Al x Ga 1− x N and the buffer layer AlN gets smaller. A reduction in the lateral coherence lengths and an increase in the edge and screw dislocations are seen as the Al x Ga 1− x N composition is varied from GaN to AlN, exhibiting a clear dependence of the crystal properties of Al x Ga 1− x N on the Al content. The bandgap of the epitaxial layers is slightly lower than predicted value due to a larger tensile strain effect on the a -axis compared to the compressive strain on the c -axis. Raman characteristics of the Al x Ga 1− x N samples exhibit a shift in the phonon peaks with the Al composition. The effect of strain on the optical phonon energies of the epitaxial layers is also discussed.

show abstract

Advantages of the AlGaN spacer in InAlN high-electron-mobility transistors grown using metalorganic vapor phase epitaxy

Cited by 6 publications

References 37 publications

High‐power‐density InAlGaN/GaN HEMT using InGaN back barrier for W‐band amplifiers

High‐power‐density InAlGaN/GaN HEMT using InGaN back barrier for W‐band amplifiers

Surface‐Oxide‐Controlled InAlGaN/GaN High‐Electron‐Mobility Transistors Using Al₂O₃‐Based Insulated‐Gate Structures with H₂O Vapor Pretreatment

Strain-stress study of AlxGa1−xN/AlN heterostructures on c-plane sapphire and related optical properties

Contact Info

Product

Resources

About

Advantages of the AlGaN spacer in InAlN high-electron-mobility transistors grown using metalorganic vapor phase epitaxy

Cited by 6 publications

References 37 publications

High‐power‐density InAlGaN/GaN HEMT using InGaN back barrier for W‐band amplifiers

High‐power‐density InAlGaN/GaN HEMT using InGaN back barrier for W‐band amplifiers

Surface‐Oxide‐Controlled InAlGaN/GaN High‐Electron‐Mobility Transistors Using Al2O3‐Based Insulated‐Gate Structures with H2O Vapor Pretreatment

Strain-stress study of AlxGa1−xN/AlN heterostructures on c-plane sapphire and related optical properties

Contact Info

Product

Resources

About

Surface‐Oxide‐Controlled InAlGaN/GaN High‐Electron‐Mobility Transistors Using Al₂O₃‐Based Insulated‐Gate Structures with H₂O Vapor Pretreatment