Query: GaN metal-oxide-semiconductor high-electron-mobility- transistor with atomic layer deposited Al2O3 as gate dielectric

Candidate papers:

abstract: We report on a GaN metal oxide semiconductor high electron mobility transistor (MOS HEMT) using atomic layer deposited (ALD) Al2O3 as the gate dielectric. Compared to a conventional GaN high electron mobility transistor (HEMT) of similar design, the MOS HEMT exhibits several orders of magnitude lower gate leakage and several times higher breakdown voltage and channel current. This implies that the ALD Al2O3/AlGaN interface is of high quality and the ALD Al2O3/AlGaN/GaN MOS HEMT is of high potential for high power rf applications. In addition, the high quality ALD Al2O3 gate dielectric allows the effective two dimensional (2D) electron mobility at the AlGaN/GaN heterojunction to be measured under a high transverse field. The resulting effective 2D electron mobility is much higher than that typical of Si, GaAs or InGaAs metal oxide semiconductor field effect transistors (MOSFETs)
author_names: Peide D Ye

B Y Yang

Kwok K Ng

Jeff Bude

Glen David Wilk

S Halder

James C M Hwang
title: GaN metal oxide semiconductor high electron mobility transistor with atomic layer deposited Al2O3 as gate dielectric
year: 2005

abstract: We investigate the characteristics of AlGaN/GaN metal insulator semiconductor high electron mobility transistors (MIS HEMTs) with a NbAlO/Al2O3 lamination dielectric deposited by atomic layer deposition (ALD) as the gate insulator. A large gate voltage swing (GVS) of 3.96 V and a high breakdown voltage of 150 V for the MIS HEMT were obtained. We present the gate leakage current mechanisms and analyze the reason for the reduction of the leakage current. Compared with traditional HEMTs, the maximum drain current is improved to 960 mA/mm, indicating that NbAlO layers could reduce the surface related depletion of the channel layer and increase the sheet carrier concentration. In addition, the maximum oscillation frequency of 38.8 GHz shows that the NbAlO high k dielectric can be considered as a potential gate oxide comparable with other dielectric insulators.
author_names: Zhi-wei Bi

Yue Hao

Qian Feng

Zhi-Yuan Gao

Jincheng Zhang

Wei Mao

Kai Zhang

Xiao-hua Ma

Hong-xia Liu

Lin'an Yang

Nan Mei

Yong-Ming Chang
title: AlGaN/GaN Metal Insulator Semiconductor High Electron Mobility Transistor Using a NbAlO/Al2O3 Laminated Dielectric by Atomic Layer Deposition
year: 2012

abstract: The oxide/semiconductor interface state density (Dit) in Al2O3/AlGaN/GaN metal oxide semiconductor high electron mobility transistor (MOS HEMT) structures with gate oxides grown by atomic layer deposition at low deposition temperature is analyzed in this work. MOS HEMT structures with Al2O3 gate oxide were deposited at 100 and 300 degC using trimethylaluminum precursor and H2O and O3 oxidation agents. The structures were found to show negative net charge at oxide/barrier interface with density (Nint) of 1013 cm 2, which was attributed to the reduction of barrier surface donor density (NDS) Dit was determined using capacitance transient techniques, and the results were assessed by the simulations of the capacitance voltage characteristics affected by interface traps. The results indicate a lower interface quality of the sample with Al2O3 grown using O3 agent compared to those with H2O, even though the former provided lowest gate leakage among the analyzed structures. Moreover, to uncover the NDS nature, Dit.
author_names: Milan Tapajna

Lukas Valik

Filip Gucmann

Dagmar Gregusova

Karol Frohlich

S Hascik

Edmund Dobrocka

Lajos Toth

Bela Pecz

Jan Kuzmik
title: Low temperature atomic layer deposition grown Al2O3 gate dielectric for GaN/AlGaN/GaN MOS HEMTs: Impact of deposition conditions on interface state density
year: 2017

abstract: We report on a GaN metal oxide semiconductor high electron mobility transistor (MOS HEMT) using atomic layer deposited (ALD) Al2O3 as the gate dielectric. Through further decreasing the thickness of the gate oxide to 3.5 nm and optimizing the device fabrication process, a device with maximum transconductance of 150 mS/mm was produced. The drain current of this 0.8 mm gate length MOS HEMT could reach 800 mA/mm at +3.0 V gate bias. Compared to a conventional AlGaN/GaN HEMT of similar design, better interface property, lower leakage current, and smaller capacitance voltage (C V) hysteresis were obtained, and the superiority of this MOS HEMT device structure with ALD Al2O3 gate dielectric was exhibited.
author_names: Yuanzheng Yue

Yue Hao

Qian Feng

Jincheng Zhang

Xiao-hua Ma

JinYu Ni
title: Study of GaN MOS HEMT using ultrathin Al2O3 dielectric grown by atomic layer deposition
year: 2009

abstract: We report on an AlGaN/GaN metal oxide semiconductor high electron mobility transistor (MOS HEMT) using thermal oxidation of electron beam deposited aluminum as the gate dielectric. This novel dielectric deposition process is simple, and less expensive than electron cyclotron resonance (ECR) plasma oxidation of Al or atomic layer deposited (ALD) Al2O3. The X ray Photoelectron Spectroscopy (XPS) Ols spectrum showed that the Al2O3 with a bandgap of 7.8 eV was obtained in this specimen. The resulted MOS HEMT exhibits several orders of magnitude lower gate leakage, larger drain saturation current and larger gate voltage swing compared to a conventional AlGaN/GaN high electron mobility transistor (HEMT) of similar design. The MOS HEMT is therefore a viable alternative to regular HEMTs for high power, high frequency and high temperature applications.
author_names: Hongwei Chen

Jinyan Wang

Chuan Xu

Min Yu

Yang Fu

Zhihua Dong

Fujun Xu

Yilong Hao

Cheng P Wen
title: Enhanced device performance of AlGaN/GaN HEMTs using thermal oxidation of electron beam deposited aluminum for gate oxide
venue: 2008 9th International Conference on Solid State and Integrated Circuit Technology
year: 2008

abstract: We report a GaN metal oxide semiconductor high electron mobility transistor (MOS HEMT) with atomic layer deposited (ALD) Al2O3 gate dielectric. Based on the previous work [Appl. Phys. Lett. 86 (2005) 063501] of Ye et al. by decreasing the thickness of the gate oxide to 3.5 nm and optimizing the device fabrication process, the device with maximum transconductance of 150 mS/mm is produced and discussed in comparison with the result of 100 mS/mm of Ye et al. The corresponding drain current density in the 0.8 mm gate length MOS HEMT is 800 mA/mm at the gate bias of 3.0 V. The gate leakage is two orders of magnitude lower than that of the conventional AlGaN/GaN HEMT. The excellent characteristics of this novel MOS HEMT device structure with ALD Al2O3 gate dielectric are presented.
author_names: Yue Yuan-Zheng

Hao Yue

Feng Qian

Zhang Jincheng

Ma Xiaohua

Ni Jin-Yu
title: GaN MOS HEMT Using Ultra Thin Al 2 O 3 Dielectric Grown by Atomic Layer Deposition
year: 2007

abstract: Highly scaled AlN/GaN metal oxide semiconductor heterojunction field effect transistors (MOS HFETs) with Al2O3 gate dielectrics of varying thicknesses deposited by atomic layer deposition (ALD) were fabricated, and their perfor mance was compared with Schottky barrier HFETs (SB HFETs) MOS HFETs with an ultrathin 2 nm thick Al2O3 dielectric and a gate length of 40 nm had direct current (dc) and radio frequency (RF) performances similar to the SB HFETs, with a high extrinsic transconductance of 415 mS/mm, fT of 134 GHz, and fmax of 261 GHz. In contrast, the dc and RF performances of a MOS HFET with a 4 nm thick Al2O3 dielectric were degraded by short channel effects. The 2 nm thick Al2O3 gate insulator reduced the forward bias gate current by more than two orders of magnitude. The data suggest the promise of ultrathin ALD Al2O3 gate dielectrics for next generation high speed GaN HFETs. Index Terms AlN, Al2O3, atomic layer deposition (ALD) GaN, gate dielectric, heterojunction field effect transistor (HFET) high electron mobility transistor (HEMT) metal organic semi conductor heterojunction field effect transistor (MOS HFET)
author_names: Andrea Corrion

Keisuke Shinohara

D Regan

Ivan Milosavljevic

Paul Hashimoto

P J Willadsen

Adele E Schmitz

Sung Jin Kim

C M Butler

D F Brown

Shawn D Burnham

Miroslav Micovic
title: High Speed AlN/GaN MOS HFETs With Scaled ALD {Al}_{2}{O}_{3} Gate Insulators
year: 2011

abstract: We report on a GaN metal oxide semiconductor high electron mobility transistor (MOS HEMT) using atomic layer deposited (ALD) Al2O3 as the gate dielectric.Through decreasing the thickness of the gate oxide to 3.5nm,a device with maximum transconductance of 130mS/mm is produced.The drain current of this 1mm gate length MOS HEMT can reach 720mA/mm at +3.0V gate bias.The unity current gain cutoff frequency and maximum frequency of oscillation are obtained as 10.1 and 30.8GHz,respectively.
author_names: Hao Yue

Yue Yuan-Zheng

Feng Qian

Zhang Jincheng

Ma Xiaohua

Ni Jin-Yu
title: GaN MOS HEMT Using Ultrathin Al2O3 Dielectric with fmax of 30.8GHz
year: 2007

abstract: The effects of Al2O3 gate insulator grown by atomic layer deposition (ALD) system on the two dimensional electron gas (2DEG) transport characteristics in AlGaN/GaN metal insulator semiconductor high electron mobility transistor (MISHEMT) were investigated. The shape of the electron lateral distribution in the quantum well at AlGaN/GaN interface was found to be slightly influenced by the Al2O3 thin layer. The drift mobility (md) of the electrons in ALD Al2O3/AlGaN/GaN MISHEMT is increased due to the surface passivation effects of the included dielectric layer. The higher dynamic channel current of the MISHEMT indicates that the electron saturation velocity (vsat) is also increased. These results show the improvement of the transport characteristics of 2DEG in Al2O3/AlGaN/GaN MISHEMT by the excellent properties of the Al2O3 grown by ALD.
author_names: Zhen Liu

Geok Ing Ng

S Arulkumaran

Y K T Maung

Khoon Leng Teo

S C Foo

Vicknesh Sahmuganathan
title: Improved two dimensional electron gas transport characteristics in AlGaN/GaN metal insulator semiconductor high electron mobility transistor with atomic layer deposited Al2O3 as gate insulator
year: 2009

abstract: The current research investigates the potential advantages of replacing Al2O3 with (Ta2O5)0.12(Al2O3)0.88 as a higher dielectric constant (k) gate dielectric for GaN based metal oxide semiconductor high electron mobility transistors (MOS HEMTs) The electrical characteristics of GaN capped AlGaN/GaN MOS HEMT devices with (Ta2O5)0.12(Al2O3)0.88 as the gate dielectric are compared to devices with Al2O3 gate dielectric and devices without any gate dielectric (Schottky HEMTs) Compared to the Al2O3 MOS HEMT, the (Ta2O5)0.12(Al2O3)0.88 MOS HEMT achieves a larger capacitance and a smaller absolute threshold voltage, together with a higher two dimensional electron gas carrier concentration. This results in a superior improvement of the output characteristics with respect to the Schottky HEMT, with higher maximum and saturation drain current values observed from DC current voltage measurements. Gate transfer measurements also show a higher transconductance for the (Ta2O5)0.12(Al2O3)0.88 MOS HEMT. Furthermore, from OFF state measurements, the (Ta2O5)0.12(Al2O3)0.88 MOS HEMT shows a larger reduction of the gate leakage current in comparison to the Al2O3 MOS HEMT. These results demonstrate that the increase in k of (Ta2O5)0.12(Al2O3)0.88 compared with Al2O3 leads to enhanced device performance when the ternary phase is used as a gate dielectric in the GaN based MOS HEMT.
author_names: T Partida-Manzanera

Z H Zaidi

J W Roberts

Surani Bin Dolmanan

K B Lee

P A Houston

P R Chalker

Sudhiranjan Tripathy

Richard Potter
title: Comparison of atomic layer deposited Al2O3 and (Ta2O5)0.12(Al2O3)0.88 gate dielectrics on the characteristics of GaN capped AlGaN/GaN metal oxide semiconductor high electron mobility transistors
venue: Journal of Applied Physics
year: 2019