Download or read book Fabrication and Characterization of Gallium Nitride Based High Electron Mobility Transistors for Mm wave Applications written by Benjamin Simon Strang and published by . This book was released on 2012 with total page 176 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Design Fabrication and Characterization of Gallium Nitride High electron mobility Transistors written by Jonathan George Felbinger and published by . This book was released on 2010 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Over the past few years, systems based on gallium nitride high-electron-mobility transistors (GaN HEMTs) have increasingly penetrated the markets for cellular telephone base stations, RADAR, and satellite communications. High power (several W/mm), continuous-wave (CW) operation of microwave HEMTs dissipates heat; as the device increases in temperature, its electron mobility drops and performance degrades. To enhance high-power performance and enable operation in high ambient temperature environments, the AlxGa1[-]xN/GaN epitaxial layers are attached to polycrystalline diamond substrates. e lower surface temperature rise on GaN-on- diamond is directly measured; subsequently, improved electrical performance is demonstrated on diamond versus the native (Si) substrates. Benchmark AlxGa1[-]xN/GaN devices are fabricated on SiC for comparison to diamond, Si, and bulk GaN substrates; the merits and performance of each is compared. In collaboration with Group4 Labs, X-band amplifier modules based on GaN-on-diamond HEMTs have been demonstrated for the first time. Recent efforts have focused on substituting AlxIn1[-]xN barriers in place of AlxGa1[-]xN to achieve higher output power at microwave frequencies and addressing the challenges of this new material system. Ultimately, these techniques may be combined to attain the utmost in device performance.

Download or read book Fabrication and Characterization of Gallium Nitride High Electron Mobility Transistors written by Wendi Zhou and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: "Compound semiconductor gallium nitride high electron mobility transistors (HEMTs) have significant potential for use in the electronics industry, including radar applications and microwave transmitters for communications. These wide band gap semiconductors have unique material properties that lead to devices with high power, efficiency, and bandwidth compared with existing technologies. In this work, the electrical properties of gallium nitride HEMTs on silicon substrates were studied in the context of drain characteristics and breakdown voltage. The design, fabrication, and characterization of different devices are presented, in addition to a discussion on the effects of annealing and different gate contact materials. While demonstrating considerable promise in the field of high power radio frequency (RF) applications, this technology is yet immature and several fabrication issues still need to be addressed. The goal of this work is to represent a stepping stone in further developing this technology to be used in high power devices." --

Download or read book Gallium Nitride GaN written by Farid Medjdoub and published by CRC Press. This book was released on 2017-12-19 with total page 372 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.

Download or read book Gallium Nitride High Electron Mobility Transistors on Native Substrates for Power Switching Applications written by Muhammad Alshahed and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Fabrication and Characterization of Aluminum Gallium Nitride gallium Nitride High Electron Mobility Transistors written by Vinayak Tilak and published by . This book was released on 2002 with total page 312 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book AlGaN GaN Based Millimeter Wave High Electron Mobility Transistors written by Christian Haupt and published by . This book was released on 2011 with total page 175 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this work a scaling approach is studied to develop a transistor technology which achieves a high gain as well as a high output power at W-band frequencies and can be applied in the existing fabrication process for MMICs. Following the theoretical scaling rules for field effect transistors lateral and vertical critical dimensions of 100 nm and 10 nm must be achieved, respectively. Therefore various new fabrication processes were developed to enable the new critical dimensions with a sufficient production yield for MMIC fabrication. Transistors fabricated with these methods were evaluated regarding the influence of the scaled geometries on the device characteristics using S-parameter as well as DC-measurements. As a result a transistor technology could be established with a transconductance above 600 mS/mm which is one of the highest reported values for GaN-based HEMTs so far. Furthermore, these transistors feature a very low parasitic capacitance of 0.3 pF/mm and can as a consequence achieve a current-gain cut-off frequency of more than 110 GHz. Besides the high frequency characteristics short channel effects and their influence on the device characteristics were also evaluated. The scaled transistors are dominated by a drain induced barrier lowering (DIBL) and a critical aspect ratio of approximately 14 is necessary to suppress the DIBL-effect in GaN-HEMTs.

Download or read book Optimization and Characterization of GaN based High Electron Mobility Transistors written by Haifeng Sun and published by . This book was released on 2012-01 with total page 153 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Fabrication and Electrical Measurements of Gallium Nitride High Electron Mobility Transistors written by Yi Fan Qi and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: "Gallium nitride (GaN) high electron mobility transistors (HEMTs) have a potential in electronic fields such as broadband communication and radar applications. GaN possesses many advantages including a direct and wide bandgap, making GaN HEMTs ideal to high voltage and high temperature. Experiments have yielded devices with high power output efficiency and bandwidth compared to other modern transistor devices. In this work, GaN HEMTs on silicon substrates with various gate lengths have been designed and fabricated. The current-voltage characteristics and breakdown voltages of the HEMTs have been measured. The design, fabrication, and characterization of different devices were presented, as well as the measurements and discussion of devices under effects of heat treatment. Although the fabrication technology is still immature and under development, GaN HEMTs have shown promising results in radio frequency, high power, and wireless power transfer applications. The goal of this work is to investigate the electrical properties of the GaN HEMTs and to develop this technology in high power devices in the future." --

Download or read book GaN based Tri gate High Electron Mobility Transistors written by Erdin Ture and published by Fraunhofer Verlag. This book was released on 2018 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The rapidly-growing data throughput rates in a wide range of wireless communication applications are pushing the established semiconductor device technologies to their limits. Considerably higher levels of solid-state output power will therefore be needed to meet the demand in the next generation satellite communications as well as the RADAR systems. Owing to their superior material properties such as high breakdown fields and peak electron velocities, GaN-based high electron mobility transistors (HEMTs) have recently prevailed in high-power systems operating in the microwave frequency bands. On the other hand at the millimetre-wave (MMW) and sub-MMW frequencies, highly-scaled GaN HEMTs are prone to experiencing deteriorated high frequency characteristics which severely limit the high-power performance. In an attempt to overcome this, 3-dimensional GaN HEMT devices featuring the Tri-gate topology are developed in this work, exhibiting enhanced performance in terms of both off- and on-state figures of merit. The demonstrated results promote the great potential of Tri-gate GaN HEMTs for both MMW power amplifier and high-speed logic applications.

Download or read book Fabrication and Characterization of AlGaN GaN Metal Insulator Semiconductor High Electron Mobility Transistors for High Power Applications written by Anthony Calzolaro and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Analysis and Optimization of AlGaN GaN High Electron Mobility Transistors for Microwave Applications written by Michael Hosch and published by Cuvillier Verlag. This book was released on 2011-08-08 with total page 129 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.

Download or read book Fabrication Characterization and Simulation of Gallium Nitride Heterojunction Field Effect Transistors written by Joseph Record and published by . This book was released on 2016 with total page 96 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis presents the fabrication, characterization, and off-state gate leakage simulation of Al x Ga 1−x N/GaN Heterojunction Field-Effect Transistors (HFETs). GaN HFETs are promising devices for high power, high frequency applications such as microwave amplifiers. This is due to the numerous benefits of the GaN material system including high electron mobility, breakdown field, saturation velocity, and thermal conductivity. This thesis is broken down into two major components. The first and most significant covers the fabrication and characterization of Al x Ga 1−x N/GaN HFETs. Devices were fabricated at McGill University’s Nanotools Microfabrication laboratory using a custom designed process flow. This process flow builds on previous work and presents Ohmic contact results of Ti/Al/Ti/Au and Ti/Al/Ti/Al/Ti/Au metalizations. A complete description of the process flow is provided including technology characterization results, such as mesa height profiling, where applicable. Electrical characterization of fabricated devices is performed. Results show an average contact resistance across temperature of 3.39Ωmm for the Ti/Al/Ti/Au metalization and 3.22Ωmm for the Ti/Al/Ti/Al/Ti/Au metalization. Full contact resistance results are provided over a wide range of temperature. The Ti-Al multi-layer metalization also outperforms the Ti/Al/Ti/Au metalization in terms of drain current density ( 0.12A/mm vs. 0.09A/mm ) and transconductance ( 60mS/mm vs. 40mS/mm ). Off-state gate leakage and current-voltage profiling are also carried out. The second part of this thesis concerns gate leakage current in Al x Ga 1−x N/GaN HFETs. A new off-state gate leakage model is presented to determine the variation in leakage mechanisms with the change in barrier layer aluminum mole fraction. A new metric of turning point is introduced to show where Fowler-Nordheim tunneling becomes the dominant leakage mechanism. Results show that as Al mole fraction is increased, the turning point becomes more negative and total gate leakage increases. Finally, improvements to the fabrication process and simulations are presented.

Download or read book Fabrication Characterization and Modeling of AlGaN GaN High Electron Mobility Transistors written by Ekaterina Harvard and published by . This book was released on 2013 with total page 230 pages. Available in PDF, EPUB and Kindle. Book excerpt: Initially, advances in the high frequency markets were begun by work in Gallium Arsenide systems. In recent years, however, the focus has shifted to the promise of ever higher power at ever higher frequency with the emergence of wide bandgap group III-V semiconductors, including Gallium Nitride. One area receiving attention is that of novel passivation materials for the active areas of AlGaN/GaN devices. Passivation is a critical issue because surface trapping effects are essentially unavoidable, even with the highest queality epitaxial layers, due to the polarized nature of the material. The question then becomes, which passivation materials offer the best mitigation of surface trapping effects with the least impact on parasitic elements detrimental to device performance. In this work, AlGaN/GaN devices passivated with AlSiN for both high frequency and high power operation are studied. The high frequency devices were fabricated alongside devices passivated with SiN, a standard passivation material, and characterized for both small signal and large signal performance. The AlSiN passivation was found to enhance both small and large signal performance, and so another set of devices was fabricated with high voltage, high power switching as the intended application. These devices were characterized for off-state breakdown, which was more than 4 times that of typical SiN-passivated devices, and time-domain and loadline measurements were performed.

Download or read book Fabrication and Characterization of AlGaN GaN High Electron Mobility Transistors written by Peter Javorka and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Fabrication and Characterization of AIGaN GaN High Electron Mobility Transistors written by Peter Javorka and published by . This book was released on 2004 with total page 244 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Design and Fabrication of Boron containing III nitrides Based High Electron Mobility Transistors written by Vinod Ravindran and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: GaN-based HEMTs are among the most promising candidates for high-power and high-frequency applications; a niche for millimeter-wave technologies. Nitride materials indeed outperform other mainstream III-V materials (InP or GaAs) because of several properties, including wider bandgaps, high peak and saturation velocities, large breakdown voltages, together with good thermal conductivities. Nonetheless, the state-of-the-art of nitrides is not yet industrially mature to exploit the entire millimeter-wave range. A way to push further performance is to develop innovative designs, notably by exploring novel materials. The purpose of this research was therefore to investigate the use of boron-containing III-nitrides in high electron mobility transistors (HEMTs). The study was first conducted theoretically, through solving the Schrodinger-Poisson equation. Key parameters and relevant equations were derived to implement BGaN materials in our simulations. A GaN/ultrathin-BGaN/GaN heterojunction was showed to provide an electrostatic barrier to electrons and to improve the confinement of the two-dimensional electron gas. GaN back-barrier layers happen to limit leakage in the GaN buffer thanks to two effects: (i) a polarization-induced band discontinuity and (ii) a resistive barrier originating from excellent insulation properties of BGaN. The study was then, experimentally, several growth campaigns were carried out that led to the fabrication of devices. First, we confirmed the key characteristics of BGaN materials by electrical and optical measurements. Second, we demonstrated the evidence of a significant enhancement of performance of standard AlGaN/GaN structures by the introduction of a BGaN layer in the buffer layer. Compared to conventional AlGaN/GaN HEMTs, structures grown with BGaN back-barriers showed a significant improvement of static performances, transport properties, and trapping effects involving a limited current collapse in dynamic regime.