Download or read book Poly Si Gate Electrodes for AlGaN GaN HEMT with High Reliability and Low Gate Leakage Current written by and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Handbook for III V High Electron Mobility Transistor Technologies written by D. Nirmal and published by CRC Press. This book was released on 2019-05-14 with total page 430 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book focusses on III-V high electron mobility transistors (HEMTs) including basic physics, material used, fabrications details, modeling, simulation, and other important aspects. It initiates by describing principle of operation, material systems and material technologies followed by description of the structure, I-V characteristics, modeling of DC and RF parameters of AlGaN/GaN HEMTs. The book also provides information about source/drain engineering, gate engineering and channel engineering techniques used to improve the DC-RF and breakdown performance of HEMTs. Finally, the book also highlights the importance of metal oxide semiconductor high electron mobility transistors (MOS-HEMT). Key Features Combines III-As/P/N HEMTs with reliability and current status in single volume Includes AC/DC modelling and (sub)millimeter wave devices with reliability analysis Covers all theoretical and experimental aspects of HEMTs Discusses AlGaN/GaN transistors Presents DC, RF and breakdown characteristics of HEMTs on various material systems using graphs and plots
Download or read book Power Electronics Handbook written by Muhammad H. Rashid and published by Elsevier. This book was released on 2023-09-27 with total page 1472 pages. Available in PDF, EPUB and Kindle. Book excerpt: Power Electronics Handbook, Fifth Edition delivers an expert guide to power electronics and their applications. The book examines the foundations of power electronics, power semiconductor devices, and power converters, before reviewing a constellation of modern applications. Comprehensively updated throughout, this new edition features new sections addressing current practices for renewable energy storage, transmission, integration, and operation, as well as smart-grid security, intelligent energy, artificial intelligence, and machine learning applications applied to power electronics, and autonomous and electric vehicles. This handbook is aimed at practitioners and researchers undertaking projects requiring specialist design, analysis, installation, commissioning, and maintenance services. Provides a fully comprehensive work addressing each aspect of power electronics in painstaking depth Delivers a methodical technical presentation in over 1500 pages Includes 50+ contributions prepared by leading experts Offers practical support and guidance with detailed examples and applications for lab and field experimentation Includes new technical sections on smart-grid security and intelligent energy, artificial intelligence, and machine learning applications applied to power electronics and autonomous and electric vehicles Features new chapter level templates and a narrative progression to facilitate understanding
Download or read book AlGaN GaN HEMTs Reliability Degradation Modes and Analysis written by Ponky Ivo and published by Cuvillier. This book was released on 2012-10-25 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: AlGaN/GaN HEMTs reliability and stability issues were investigated in dependence on epitaxial design and process modification. DC-Step-Stress-Tests have been performed on wafers as a fast device robustness screening method. As a criterion of robustness they deliver a critical source-drain voltage for the onset of degradation. Several degradation modes were observed which depend on epi design, epi quality and process technology. Electrical and optical characterizations together with electric field simulations were performed to get insight into respective degradation modes. It has been found that AlGaN/GaN HEMT devices with GaN cap show higher critical source-drain voltages as compared to non-capped devices. Devices with low Al concentration in the AlGaN barrier layer also show higher critical source-drain voltages. Superior stability and robustness performance have been achieved from devices with AlGaN backbarrier epi design grown on n-type SiC substrate. For the onset on any degradation modes the presence of high electrical fields is most decisive for ON- and OFF-state operation conditions. Therefore careful epi design to reduce high electric field is mandatory. It is also shown that epi buffer quality and growth process have a great impact on device robustness. Defects such as point defects and dislocations are assumed to be created initially during stressing and accumulated to larger defect clusters during device stressing. Electroluminescence (EL) measurements were performed to detect early degradation. Extended localized defects are resulting as bright spots at OFF-state conditions in conjunction with a gate leakage increase.
Download or read book Reliability Assessment of GaN HEMTs on Si Substrate with Ultra short Gate Dedicated to Power Applications at Frequency Above 40 GHz written by Hadhemi Lakhdhar and published by . This book was released on 2017 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This Ph.D. work focuses on the reliability assessment of ultra-short gate AlGaN/GaN high electron mobility transistor (HEMT) on silicon substrate dedicated to power applications at frequency above 40GHz. It was carried out within IMS Bordeaux and IEMN Lille laboratories.This work initially compares AlGaN/GaN HEMTs grown by MOCVD with those grown using MBE, through electrical characterization.In particular, the device geometry impact on the device performances has been studies by static electrical characterization.Step-stress experiments are performed to investigate reliability assessment of ultra-short gate AlGaN/GaN high electron mobility transistor (HEMT) on Si substrate. A methodology based on a sequence of step stress tests has been defined for in-situ diagnosis of a permanent degradation and of a degradation which is identified by a drain current transient occurring during each step of the ageing sequence . The same stress conditions were applied on HEMTs with different geometries. It is found no evolution of the drain current during non stressful steps. The value of the critical degradation voltage beyond which the stress drain current starts to decrease significantly is also found dependent on the stress bias conditions, the gate-drain distance and the gate length. Moreover, the safe operating area of this technology has been determined.
Download or read book Advanced GaN Devices and Technology for Rf and Power Switching Applications written by Bo Song and published by . This book was released on 2016 with total page 348 pages. Available in PDF, EPUB and Kindle. Book excerpt: GaN-based devices show great potential for high-speed RF power applications as well as power switching applications due to the high electron velocity and high breakdown field in GaN over Si, GaAs and SiC. Another unique property of III-V nitride materials (GaN, AlN, InN) is polarization, which can be engineered to induce 2-dimensional electron gas (2DEG) at heterojunction interfaces as well as induce 3-D electron gas in thick (bulk) layers by grading the alloy composition of the layers, e.g. AlGaN, without impurity doping. This unconventional doping scheme is termed as polarization-doping or Pi-doping. This work focuses on device development and proposals to advance GaN technologies for RF and power switching applications. During the quest to realize THz GaN transistors, it has been identified that the ultimate factors limiting the GaN high electron mobility transistors (HEMTs) are the intrinsic transconductance (gm) and the fringing capacitance (Cfringing) associated with the T-gate: speed gm/Cfringing. In InAlN/GaN HEMTs, the device current gain cut-off speed is increased from 230 GHz to >300 GHz by reducing Cfringing and further increased to ~ 400 GHz by improving gm. Effects of scaling the source-drain distance on ultra-scaled devices are also studied. Low leakage and low current collapse (or frequency dispersion) are crucial for transistors. A record-low leakage of 1x10-12 A/mm simultaneously with a low current collapse is achieved in AlGaN/GaN-on-Si HEMTs employing the regrown ohmic contact technology. The device improvement is attributed to the contact regrowth since generation of surface traps is minimized by avoiding the conventional high temperature annealing process to form alloyed ohmic contacts. For high-voltage high-current power switching applications (>100 kW), vertical devices are highly desirable over lateral ones. To this end, we have proposed a series of GaN devices grown on bulk GaN substrates and employing the unique feature in the GaN material family - polarization doping. Analytical modeling suggests that at the same breakdown voltage, a up to 2x lower specific on-resistance (Ron,sp) can be achieved in Pi-doped devices compared to impurity doped GaN power devices. High voltage impurity and Pi-doped GaN p-n diodes with a breakdown voltage (BV) >1.2 kV and avalanche breakdown capability have been developed experimentally. Another concept called GaN Lateral Polar Super Junctions (LPSJ) is also proposed and theoretically analyzed, featuring uniformly Pi-doped n/p-pillars to overcome the conventional tradeoff between BV and Ron,sp in a unipolar drift region of a power device. The design space for GaN LPSJs is explored using a 2D analytical model of BV and Ron,sp under both charge balanced and imbalanced conditions.
Download or read book Normally Off AlGaN GaN HEMT on Si Substrate with Selectively Dry etched Recessed Gate and Polarization charge compensation doped GaN Cap Layer written by and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: We demonstrate a recessed-gate normally off AlGaN/GaN high-electron-mobility transistor (HEMT) on a silicon substrate that provides a precisely controllable threshold voltage ( V th ). To ensure V th uniformity, dry-etching of GaN with high etching selectivity between GaN and AlGaN is developed. Furthermore, to introduce selective dry-etching in the HEMT fabrication process, we propose a delta-doped GaN cap structure that enables negative polarization charges between the GaN cap and the AlGaN barrier to be compensated. Combining these two technologies, we fabricate recessed-gate normally off metal–insulator–semiconductor HEMTs with a subthreshold slope of 130 mV/dec and an on–off drain current ratio exceeding 10 7 .
Download or read book Electrical Electronics Abstracts written by and published by . This book was released on 1997 with total page 1904 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Power GaN Devices written by Matteo Meneghini and published by Springer. This book was released on 2016-09-08 with total page 383 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.
Download or read book Wide Bandgap Based Devices written by Farid Medjdoub and published by MDPI. This book was released on 2021-05-26 with total page 242 pages. Available in PDF, EPUB and Kindle. Book excerpt: Emerging wide bandgap (WBG) semiconductors hold the potential to advance the global industry in the same way that, more than 50 years ago, the invention of the silicon (Si) chip enabled the modern computer era. SiC- and GaN-based devices are starting to become more commercially available. Smaller, faster, and more efficient than their counterpart Si-based components, these WBG devices also offer greater expected reliability in tougher operating conditions. Furthermore, in this frame, a new class of microelectronic-grade semiconducting materials that have an even larger bandgap than the previously established wide bandgap semiconductors, such as GaN and SiC, have been created, and are thus referred to as “ultra-wide bandgap” materials. These materials, which include AlGaN, AlN, diamond, Ga2O3, and BN, offer theoretically superior properties, including a higher critical breakdown field, higher temperature operation, and potentially higher radiation tolerance. These attributes, in turn, make it possible to use revolutionary new devices for extreme environments, such as high-efficiency power transistors, because of the improved Baliga figure of merit, ultra-high voltage pulsed power switches, high-efficiency UV-LEDs, and electronics. This Special Issue aims to collect high quality research papers, short communications, and review articles that focus on wide bandgap device design, fabrication, and advanced characterization. The Special Issue will also publish selected papers from the 43rd Workshop on Compound Semiconductor Devices and Integrated Circuits, held in France (WOCSDICE 2019), which brings together scientists and engineers working in the area of III–V, and other compound semiconductor devices and integrated circuits. In particular, the following topics are addressed: – GaN- and SiC-based devices for power and optoelectronic applications – Ga2O3 substrate development, and Ga2O3 thin film growth, doping, and devices – AlN-based emerging material and devices – BN epitaxial growth, characterization, and devices
Download or read book GaN SiC Power Technologies 5 written by K. Shenai and published by The Electrochemical Society. This book was released on 2015 with total page 144 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book AlGaN GaN MOS HEMTs on Si Employing Sputtered TaN based Electrodes and HfO2 Gate Insulator written by and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Understanding Material and Process Limits for High Breakdown Voltage AlGaN GaN HEMTs written by Yuvaraj Dora and published by . This book was released on 2006 with total page 280 pages. Available in PDF, EPUB and Kindle. Book excerpt: The breakdown voltage in AlGaN/GaN HEMTs is known to be triggered by the gate leakage caused by the electric field crowding at the drain-side edge of the gate. The effect of gate leakage on breakdown is mitigated by relieving the peak electric field at the drain-side edge of the gate and by decreasing the tunnelling probability with the use of gate dielectrics.
Download or read book Chemical Abstracts written by and published by . This book was released on 2002 with total page 2616 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Optimization of the Elaboration of Insulating Layers for the Gate Structures and the Passivation of MIS HEMT Transistors on GaN written by Richard Meunier and published by . This book was released on 2016 with total page 141 pages. Available in PDF, EPUB and Kindle. Book excerpt: With its large band gap, Gallium Nitride (GaN) semiconductor is one of the most promising materials for new power devices generation thanks to its outstanding material properties for high voltage, temperature and frequency applications. The main objective of this thesis was the development and optimization of the insulating step taking place in the elaboration of MIS-HEMT transistors on an AlGaN/GaN heterstroctructure. In order to reduce gate leakage currents without degrading the device properties, alumina Al2O3 deposited by ALD was chosen as a gate dielectric. The study was first centered on the influence of surface treatments, chemical or plasma, regarding surface contamination. Their impact was analyzed through XPS and AFM. Secondly, electrical measures were performed on complete MIS-HEMT diodes and transistors to evaluate the influence of the alumina insulating layer depending on the ALD deposition method. Lastly, partial and full recess of the AlGaN barrier was studied via ICP-RIE etching. The gate dielectric deposition is one of the crucial steps intervening in the HEMT creation process. The quality and control at the Al2O2/AlGaN interface being paramount, it will directly influence the device's electric properties. This involves control ing the semiconductor surface, but also the nature and deposition technique of the dielectric. As such, an ammonia-based treatment at high temperature appears to be the most efficient in reducing native oxygen contamination. Regarding electric performances, C(V) and Id(Vg) measures showed the superiority of PEALD compared to traditional thermal ALD deposition. This can be explained by the fact that the oxygen plasma used as oxydant during the alumina deposition by PEALD seems to clean the surface during the first cycles, mostly by reducing carbon contamination. This allowed to achieve a better interface between the semiconductor and the insulting layer, thus limiting traps at the interface or in the oxyde. This allows to considerably reduce gate leakage currents, without degrading the quality and transition sharpness between the on and off state. Moreover, the realized HEMTs being normally-off, gate recess etching via ICP-RIE was implemented in order to make the threshold voltage less negative. This was successfully achieved, especially through the realization of a normally-off transistors thanks to a full recess of the AlGaN barrier under the gate. State of the art results were achieved through a simple approach, and a robust and highly reproducible transistor elaboration process, with great reduction of gate leakage currents and a record sub-threshold slope. In order to complete the study, it will be necessary in the future to proceed to viability studies, especially through dynamic electric evaluation, in order to evaluate for instance Ron degradation phenomenons.
Download or read book Physics and Technology of High k Gate Dielectrics 4 written by Samares Kar and published by The Electrochemical Society. This book was released on 2006 with total page 565 pages. Available in PDF, EPUB and Kindle. Book excerpt: This issue covers, in detail, all aspects of the physics and the technology of high dielectric constant gate stacks, including high mobility substrates, high dielectric constant materials, processing, metals for gate electrodes, interfaces, physical, chemical, and electrical characterization, gate stack reliability, and DRAM and non-volatile memories.
Download or read book Advanced Processing for Scaled Depletion and Enhancement mode AlGaN GaN HEMTs written by Michael L. Schuette and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: To overcome processing challenges associated with aggressive scaling of GaN-based HEMTs we have developed technology enabling us to construct gates shorter than 30 nm and to precisely remove GaN and AlGaN from the gate area of (GaN/)AlGaN/GaN HEMTs to reduce d. The optical transparency of GaN has made consistent sub-100-nm gate definition challenging for electron beam lithography tools that employ optical height detection, and our transparent substrate electron beam focusing strategy eliminates such difficulty. Recessed gate GaN-based HEMTs have historically been plagued with high gate leakage and DC-RF current dispersion due to ion damage incurred during recess etching, but the N2/Cl2/O2 inductively-coupled plasma etch process described herein can provide very high GaN over AlGaN etch selectivity and does not require energetic ions.
