Gallium Nitride-enabled High Frequency and High Efficiency Power Conversion
Gallium Nitride-enabled High Frequency and High Efficiency Power Conversion

Author: Gaudenzio Meneghesso

Publisher: Springer

Published: 2018-05-12

Total Pages: 242

ISBN-13: 331977994X

DOWNLOAD EBOOK

This book demonstrates to readers why Gallium Nitride (GaN) transistors have a superior performance as compared to the already mature Silicon technology. The new GaN-based transistors here described enable both high frequency and high efficiency power conversion, leading to smaller and more efficient power systems. Coverage includes i) GaN substrates and device physics; ii) innovative GaN -transistors structure (lateral and vertical); iii) reliability and robustness of GaN-power transistors; iv) impact of parasitic on GaN based power conversion, v) new power converter architectures and vi) GaN in switched mode power conversion. Provides single-source reference to Gallium Nitride (GaN)-based technologies, from the material level to circuit level, both for power conversions architectures and switched mode power amplifiers; Demonstrates how GaN is a superior technology for switching devices, enabling both high frequency, high efficiency and lower cost power conversion; Enables design of smaller, cheaper and more efficient power supplies.

Gallium Nitride Vertical Devices for High-power and High-frequency Applications
Gallium Nitride Vertical Devices for High-power and High-frequency Applications

Author: Siwei Li

Publisher:

Published: 2020

Total Pages: 0

ISBN-13:

DOWNLOAD EBOOK

Gallium nitride (GaN) has gained considerable interest in the areas of power electronics and radio frequency (RF) devices in recent years due to its significantly higher material figure-of-merits (FOMs) than silicon (Si). The capability of operating faster as power switches also overwhelms another wide-bandgap contender, silicon carbide (SiC), especially for applications at ~600-1200 V level. GaN devices with a lateral topology such as high electron mobility transistors (HEMTs) have been extensively studied, while the development of vertical devices on high-quality free-standing GaN substrates is opening new opportunities towards improved power handling capability in high-power applications. There are still science and technology issues associated with GaN that limit its applications in high-power scenarios. One of the fundamental properties is its avalanche behavior, which is expected to be considered as a benchmark for the material but was rarely seen in GaN devices grown on foreign substrates, including sapphire, Si and SiC. Avalanche is observed and gaining increasing attention recently with the improvement of GaN-on-GaN substrate, especially in diodes. Several issues of GaN in high-power and high-speed applications are addressed in the present work. Edge terminations play a vital role in GaN devices targeting a high voltage range, and enable avalanche by optimizing the electric filed distribution, eliminating peak electric field at device edges. An ion-compensated moat etch structure is studied on GaN vertical p-n diodes. Parameters including moat etching depth and ion implantation dose are optimized. P-n diodes with a breakdown voltage (V[subscript BR]) of 1500 V and a specific on-state resistance (R[subscript ON,sp]) of 0.7 m[omega]·cm2 is demonstrated with the optimized structure, showing a device FOM of 3.2 GW·cm−2 and avalanche behavior. With avalanche performance as a prerequisite confirmed on vertical p-n diodes on bulk GaN substrates with dislocation density ranging from 1e4 cm−2 to 1e6 cm−2, the effect of dislocation density on device behavior, especially off-state leakage current is experimentally and studied in detail. The leakage mechanism is analyzed by considering its relationship to electric field and temperature. Lower leakage could be achieved on the substrate with 1e4 cm−2 dislocation density, with variable-range-hopping (VRH) procedure dominating low electric field range and Poole-Frenkel (PF) effect dominating the higher part, while VRH and other more trap-related processes may play more roles on the substrate with 1e6 cm−2 dislocation density. Large current capability is another factor for high-power applications. A DC current up to 50 A is successfully demonstrated on large-area p-n diodes by applying backside gold-to-gold thermal compression bonding. A successful scaling-up is achieved with essential factors studied. There have been few works on the RF performance of GaN vertical devices though the lateral RF devices have been widely explored. To study RF properties of GaN vertical devices, a Silvaco TCAD simulation model is established for nitride (N)-polar GaN current aperture vertical electron transistor (CAVET) based on a fitting of N-polar lateral HEMT experimental results. DC and RF properties of an N-polar CAVET are simulated, and a maximum output power of 15 W·mm−1 is expected. To experimentally demonstrate RF characteristics of a CAVET, the 1st-generation RF CAVET is then built on gallium (Ga)-polar substrate. Based on the DC characteristics, a current gain cutoff frequency (fT) at ~13 GHz is expected.

GaN-based Vertical Power Devices
GaN-based Vertical Power Devices

Author: Yuhao Zhang (Ph. D.)

Publisher:

Published: 2017

Total Pages: 170

ISBN-13:

DOWNLOAD EBOOK

Power electronics based on Gallium Nitride (GaN) is expected to significantly reduce the losses in power conversion circuits and increase the power density. This makes GaN devices very exciting candidates for next-generation power electronics, for the applications in electric vehicles, data centers, high-power and high-frequency communications. Currently, both lateral and vertical structures are considered for GaN power devices. In particular, vertical GaN power devices have attracted significant attention recently, due to the potential for achieving high breakdown voltage and current levels without enlarging the chip size. In addition, these vertical devices show superior thermal performance than their lateral counterparts. This PhD thesis addresses several key obstacles in developing vertical GaN power devices. The commercialization of vertical GaN power devices has been hindered by the high cost of bulk GaN. The first project in this PhD thesis demonstrated the feasibility of making vertical devices on a low-cost silicon (Si) substrate for the first time. The demonstrated high performance shows the great potential of low-cost vertical GaN-on-Si devices for 600-V level high-current and high-power applications. This thesis has also studied the origin of the off-state leakage current in vertical GaN pn diodes on Si, sapphire and GaN substrates, by experiments, analytical calculations and TCAD simulations. Variable-range-hopping through threading dislocations was identified as the main off-state leakage mechanism in these devices. The design space of leakage current of vertical GaN devices has been subsequently derived. Thirdly, a novel GaN vertical Schottky rectifier with trench MIS structures and trench field rings was demonstrated. The new structure greatly enhanced the reverse blocking characteristics while maintaining a Schottky-like good forward conduction. This new device shows great potential for using advanced vertical Schottky rectifiers for high-power and high-frequency applications. Finally, we investigated a fundamental and significant challenge for GaN power devices: the lack of reliable and generally useable patterned pn junctions. Two approaches have been proposed to make lateral patterned pn junctions. Two devices, junction barrier Schottky devices and super-junction devices, have been designed and optimized. Preliminary experimental results were also demonstrated for the feasibility of making patterned pn junctions and fabricating novel power devices.

Power GaN Devices
Power GaN Devices

Author: Matteo Meneghini

Publisher: Springer

Published: 2016-09-08

Total Pages: 383

ISBN-13: 3319431994

DOWNLOAD EBOOK

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.

Gallium Nitride (GaN)
Gallium Nitride (GaN)

Author: Farid Medjdoub

Publisher: CRC Press

Published: 2017-12-19

Total Pages: 372

ISBN-13: 1482220040

DOWNLOAD EBOOK

Addresses a Growing Need for High-Power and High-Frequency Transistors Gallium Nitride (GaN): Physics, Devices, and Technology offers a balanced perspective on the state of the art in gallium nitride technology. A semiconductor commonly used in bright light-emitting diodes, GaN can serve as a great alternative to existing devices used in microelectronics. It has a wide band gap and high electron mobility that gives it special properties for applications in optoelectronic, high-power, and high-frequency devices, and because of its high off-state breakdown strength combined with excellent on-state channel conductivity, GaN is an ideal candidate for switching power transistors. Explores Recent Progress in High-Frequency GaN Technology Written by a panel of academic and industry experts from around the globe, this book reviews the advantages of GaN-based material systems suitable for high-frequency, high-power applications. It provides an overview of the semiconductor environment, outlines the fundamental device physics of GaN, and describes GaN materials and device structures that are needed for the next stage of microelectronics and optoelectronics. The book details the development of radio frequency (RF) semiconductor devices and circuits, considers the current challenges that the industry now faces, and examines future trends. In addition, the authors: Propose a design in which multiple LED stacks can be connected in a series using interband tunnel junction (TJ) interconnects Examine GaN technology while in its early stages of high-volume deployment in commercial and military products Consider the potential use of both sunlight and hydrogen as promising and prominent energy sources for this technology Introduce two unique methods, PEC oxidation and vapor cooling condensation methods, for the deposition of high-quality oxide layers A single-source reference for students and professionals, Gallium Nitride (GaN): Physics, Devices, and Technology provides an overall assessment of the semiconductor environment, discusses the potential use of GaN-based technology for RF semiconductor devices, and highlights the current and emerging applications of GaN.

Gallium Nitride Power Devices
Gallium Nitride Power Devices

Author: Hongyu Yu

Publisher: CRC Press

Published: 2017-07-06

Total Pages: 298

ISBN-13: 1351767615

DOWNLOAD EBOOK

GaN is considered the most promising material candidate in next-generation power device applications, owing to its unique material properties, for example, bandgap, high breakdown field, and high electron mobility. Therefore, GaN power device technologies are listed as the top priority to be developed in many countries, including the United States, the European Union, Japan, and China. This book presents a comprehensive overview of GaN power device technologies, for example, material growth, property analysis, device structure design, fabrication process, reliability, failure analysis, and packaging. It provides useful information to both students and researchers in academic and related industries working on GaN power devices. GaN wafer growth technology is from Enkris Semiconductor, currently one of the leading players in commercial GaN wafers. Chapters 3 and 7, on the GaN transistor fabrication process and GaN vertical power devices, are edited by Dr. Zhihong Liu, who has been working on GaN devices for more than ten years. Chapters 2 and 5, on the characteristics of polarization effects and the original demonstration of AlGaN/GaN heterojunction field-effect transistors, are written by researchers from Southwest Jiaotong University. Chapters 6, 8, and 9, on surface passivation, reliability, and package technologies, are edited by a group of researchers from the Southern University of Science and Technology of China.

Gallium Nitride Power Devices
Gallium Nitride Power Devices

Author: Hongyu Yu

Publisher: CRC Press

Published: 2017-07-06

Total Pages: 301

ISBN-13: 1351767607

DOWNLOAD EBOOK

GaN is considered the most promising material candidate in next-generation power device applications, owing to its unique material properties, for example, bandgap, high breakdown field, and high electron mobility. Therefore, GaN power device technologies are listed as the top priority to be developed in many countries, including the United States, the European Union, Japan, and China. This book presents a comprehensive overview of GaN power device technologies, for example, material growth, property analysis, device structure design, fabrication process, reliability, failure analysis, and packaging. It provides useful information to both students and researchers in academic and related industries working on GaN power devices. GaN wafer growth technology is from Enkris Semiconductor, currently one of the leading players in commercial GaN wafers. Chapters 3 and 7, on the GaN transistor fabrication process and GaN vertical power devices, are edited by Dr. Zhihong Liu, who has been working on GaN devices for more than ten years. Chapters 2 and 5, on the characteristics of polarization effects and the original demonstration of AlGaN/GaN heterojunction field-effect transistors, are written by researchers from Southwest Jiaotong University. Chapters 6, 8, and 9, on surface passivation, reliability, and package technologies, are edited by a group of researchers from the Southern University of Science and Technology of China.

Vertical Gallium Nitride Fin Transistors for RF Applications
Vertical Gallium Nitride Fin Transistors for RF Applications

Author: Joshua Andrew Perozek

Publisher:

Published: 2020

Total Pages: 80

ISBN-13:

DOWNLOAD EBOOK

This thesis presents the development, fabrication, and characterization of the first vertical gallium nitride fin transistors for radio frequency applications. The basic device design is adapted from vertical fin power transistors with modifications made to improve frequency performance, system integration, and uniformity. Specifically, a new, self-aligned gate process allows for dramatic scaling of gate lengths; a highly uniform planarization process improves device yield and reliability; and layout adjustments reduce parasitics and allow for on-wafer, high-frequency testing of vertical devices. These advancements are a promising step in enabling the next generation of radio frequency electronics powered by gallium nitride.

GaN Transistors for Efficient Power Conversion
GaN Transistors for Efficient Power Conversion

Author: Alex Lidow

Publisher: John Wiley & Sons

Published: 2019-08-12

Total Pages: 470

ISBN-13: 1119594421

DOWNLOAD EBOOK

An up-to-date, practical guide on upgrading from silicon to GaN, and how to use GaN transistors in power conversion systems design This updated, third edition of a popular book on GaN transistors for efficient power conversion has been substantially expanded to keep students and practicing power conversion engineers ahead of the learning curve in GaN technology advancements. Acknowledging that GaN transistors are not one-to-one replacements for the current MOSFET technology, this book serves as a practical guide for understanding basic GaN transistor construction, characteristics, and applications. Included are discussions on the fundamental physics of these power semiconductors, layout, and other circuit design considerations, as well as specific application examples demonstrating design techniques when employing GaN devices. GaN Transistors for Efficient Power Conversion, 3rd Edition brings key updates to the chapters of Driving GaN Transistors; Modeling, Simulation, and Measurement of GaN Transistors; DC-DC Power Conversion; Envelope Tracking; and Highly Resonant Wireless Energy Transfer. It also offers new chapters on Thermal Management, Multilevel Converters, and Lidar, and revises many others throughout. Written by leaders in the power semiconductor field and industry pioneers in GaN power transistor technology and applications Updated with 35% new material, including three new chapters on Thermal Management, Multilevel Converters, Wireless Power, and Lidar Features practical guidance on formulating specific circuit designs when constructing power conversion systems using GaN transistors A valuable resource for professional engineers, systems designers, and electrical engineering students who need to fully understand the state-of-the-art GaN Transistors for Efficient Power Conversion, 3rd Edition is an essential learning tool and reference guide that enables power conversion engineers to design energy-efficient, smaller, and more cost-effective products using GaN transistors.