Charge Collection Mechanisms in AIGan/GaN MOS High Electron Mobility Transistors PDF Download
Are you looking for read ebook online? Search for your book and save it on your Kindle device, PC, phones or tablets. Download Charge Collection Mechanisms in AIGan/GaN MOS High Electron Mobility Transistors PDF full book. Access full book title Charge Collection Mechanisms in AIGan/GaN MOS High Electron Mobility Transistors by Isaak Knox Samsel. Download full books in PDF and EPUB format.
Author: Isaak Knox Samsel
Publisher:
ISBN:
Category : Electronic dissertations
Languages : en
Pages : 47
Get Book Here
Book Description
Author: Isaak Knox Samsel
Publisher:
ISBN:
Category : Electronic dissertations
Languages : en
Pages : 47
Get Book Here
Book Description
Author: Michael Hosch
Publisher: Cuvillier Verlag
ISBN: 3736938446
Category : Technology & Engineering
Languages : en
Pages : 129
Get Book Here
Book Description
This thesis deals with the analysis and optimization of some of the most prominent non-ideal effects in AlGaN/GaN high electron mobility transistors used in microwave applications as well as the optimization of the RF gain. The effect of current collapse, the root cause of leakage currents as well as field-dependent self-heating effects have been investigated by eletrical characterization using well established techniques and have been analyzed using 2-dimensional physical device simulations. It will be shown that the origin of all effects is strongly related to the device surface and some are even competing effects making device optimization a challenge. However, a detailed localization of the regions affecting device performance will be given leading to a better understanding for fabrication process optimization. Finally, I simulation study is conducted giving suggestions for RF gain improvement based on very simple device layout variations.
Author: Weikai Xu
Publisher:
ISBN:
Category :
Languages : en
Pages : 116
Get Book Here
Book Description
AlGaN/GaN HEMTs have shown great performance in high frequency and high power applications. However, since the fabrication process of GaN devices is developed in recent years, it is not as mature as the silicon technology. Device reliability is one of the major issues that limit AlGaN/GaN HEMTs reaching their potential. In this work, unstressed and stressed AlGaN/GaN HEMTs are studied through I-V characteristics and low frequency noise measurements. Both the channel and the gate stack were examined to reveal the origins for device failure. Through noise measurement of channel, traps are found at AlGaN-GaN interface. A drain noise model is established to extract noise information of the gated part of the channel. For unstressed device the Hooge mobility fluctuation model dominates the noise mechanism, while the carrier number fluctuation model fits with the data of stressed devices. Hooge parameters and trap density are extracted for the channel part.
Author: Michael James Murphy
Publisher:
ISBN:
Category :
Languages : en
Pages : 226
Get Book Here
Book Description
Author: Elio Chiodo
Publisher: Mdpi AG
ISBN: 9783036511771
Category : Technology & Engineering
Languages : en
Pages : 228
Get Book Here
Book Description
The rapid increase in new power electronic devices and converters for electric transportation and smart grid technologies requires a deep analysis of their component performances, considering all of the different environmental scenarios, overload conditions, and high stress operations. Therefore, evaluation of the reliability and availability of these devices becomes fundamental both from technical and economical points of view. The rapid evolution of technologies and the high reliability level offered by these components have shown that estimating reliability through the traditional approaches is difficult, as historical failure data and/or past observed scenarios demonstrate. With the aim to propose new approaches for the evaluation of reliability, in this book, eleven innovative contributions are collected, all focused on the reliability assessment of power electronic devices and related components.
Author: Feng Gao (Ph. D.)
Publisher:
ISBN:
Category :
Languages : en
Pages : 121
Get Book Here
Book Description
AlGaN/GaN high electron mobility transistors (HEMTs) constitute a new generation of transistors with excellent electrical characteristics and great potential to replace silicon technology in the future, especially in high power and high frequency applications. However, the poor long term reliability of these devices is an important bottleneck for their wide market insertion and limits their advanced development. This thesis tackles this problem by focusing on understanding the physics behind various degradation modes and providing new quantitative models to explain these mechanisms. The first part of the thesis, Chapters 2 and 3, reports studies of the origin of permanent structural and electrical degradation in AlGaN/GaN HEMTs. Hydroxyl groups (OH-) from the environment and/or adsorbed water on the III-N surface are found to play an important role in the formation of surface pits during the OFF-state electrical stress. The mechanism of this water-related structural degradation is explained by an electrochemical cell formed at the gate edge where gate metal, the II-N surface and the passivation layer meet. Moreover, the permanent decrease of the drain current is directly linked with the formation of the surface pits, while the permanent increase of the gate current is found to be uncorrelated with the structural degradation. The second part of the thesis, Chapters 4 and 5, identifies water-related redox couples in ambient air as important sources of dynamic on-resistance and drain current collapse in AlGaN/GaN HEMTs. Through in-situ X-ray photoelectron spectroscopy (XPS), direct signature of the water-related species is found at the AlGaN surface at room temperature. It is also found that these species, as well as the current collapse, can be thermally removed above 200 °C in vacuum conditions. An electron trapping mechanism based on H2O/H2 and H2O/O2 redox couples is proposed to explain the 0.5 eV energy level commonly attributed to surface trapping states. Moreover, the role of silicon nitride passivation in successfully removing current collapse in these devices is explained by blocking the water molecules away from the AlGaN surface. Finally, fluorocarbon, a highly hydrophobic material, is proven to be an excellent passivation to overcome transient degradation mechanisms in AlGaN/GaN HEMTs.
Author: D. Nirmal
Publisher: Springer
ISBN: 9789819775057
Category : Technology & Engineering
Languages : en
Pages : 0
Get Book Here
Book Description
This volume focuses on GaN HEMT, the most promising transistor technology for RF power applications such as 5G communications, space and defense. The contents include accurate small signal models required to predict the RF power performance of RF electronic circuits, large signal modeling of GaN HEMTs, accurate and compact physical models to assist the RF circuit designers to optimize GaN HEMT-based power amplifiers and integrated circuits, among others. The book also covers thermal resistance modeling of GaN HEMTs, charge-based compact models, and surface potential-based models to study the impact of gate leakage current on the RF power performance of GaN HEMTs. This book also deals with the analytical modeling of intrinsic charges and surface potential of GaN HEMTs, physical modeling of charge trapping, neural network-based GaN HEMT models, numerical-based GaN HEMT models, modeling of short channel effects in GaN HEMTs, modeling of parasitic capacitances and resistances, modelingof current collapse and kink effects in HGaN HEMTs, etc. This volume will be a useful to those in industry and academia.
Author: Matteo Meneghini
Publisher: Springer
ISBN: 3319431994
Category : Technology & Engineering
Languages : en
Pages : 383
Get Book Here
Book Description
This book presents the first comprehensive overview of the properties and fabrication methods of GaN-based power transistors, with contributions from the most active research groups in the field. It describes how gallium nitride has emerged as an excellent material for the fabrication of power transistors; thanks to the high energy gap, high breakdown field, and saturation velocity of GaN, these devices can reach breakdown voltages beyond the kV range, and very high switching frequencies, thus being suitable for application in power conversion systems. Based on GaN, switching-mode power converters with efficiency in excess of 99 % have been already demonstrated, thus clearing the way for massive adoption of GaN transistors in the power conversion market. This is expected to have important advantages at both the environmental and economic level, since power conversion losses account for 10 % of global electricity consumption. The first part of the book describes the properties and advantages of gallium nitride compared to conventional semiconductor materials. The second part of the book describes the techniques used for device fabrication, and the methods for GaN-on-Silicon mass production. Specific attention is paid to the three most advanced device structures: lateral transistors, vertical power devices, and nanowire-based HEMTs. Other relevant topics covered by the book are the strategies for normally-off operation, and the problems related to device reliability. The last chapter reviews the switching characteristics of GaN HEMTs based on a systems level approach. This book is a unique reference for people working in the materials, device and power electronics fields; it provides interdisciplinary information on material growth, device fabrication, reliability issues and circuit-level switching investigation.
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :
Get Book Here
Book Description
Abstract: The transport mechanism of reverse surface leakage current in the AlGaN/GaN high-electron mobility transistor (HEMT) becomes one of the most important reliability issues with the downscaling of feature size. In this paper, the research results show that the reverse surface leakage current in AlGaN/GaN HEMT with SiN passivation increases with the enhancement of temperature in the range from 298 K to 423 K. Three possible transport mechanisms are proposed and examined to explain the generation of reverse surface leakage current. By comparing the experimental data with the numerical transport models, it is found that neither Fowler–Nordheim tunneling nor Frenkel–Poole emission can describe the transport of reverse surface leakage current. However, good agreement is found between the experimental data and the two-dimensional variable range hopping (2D-VRH) model. Therefore, it is concluded that the reverse surface leakage current is dominated by the electron hopping through the surface states at the barrier layer. Moreover, the activation energy of surface leakage current is extracted, which is around 0.083 eV. Finally, the SiN passivated HEMT with a high Al composition and a thin AlGaN barrier layer is also studied. It is observed that 2D-VRH still dominates the reverse surface leakage current and the activation energy is around 0.10 eV, which demonstrates that the alteration of the AlGaN barrier layer does not affect the transport mechanism of reverse surface leakage current in this paper.
Author: Peter Javorka
Publisher:
ISBN:
Category :
Languages : en
Pages :
Get Book Here
Book Description
