Author: Jin ChenPublisher:
ISBN:
Category : Electronic dissertations
Languages : en
Pages : 69
Book Description
Radiation Response and Reliability of AlGaN/GaN HEMTs
Author: Jin ChenPublisher:
ISBN:
Category : Electronic dissertations
Languages : en
Pages : 69
Book Description
Radiation Response and Reliability of High Speed AlGaN/GaN HEMTs
Author: Jin ChenPublisher:
ISBN:
Category : Electronic dissertations
Languages : en
Pages : 95
Book Description
Bias Dependence of Radiation Response and Reliability of AlGaN/GaN HEMTs
Author: Rong JiangPublisher:
ISBN:
Category : Electronic dissertations
Languages : en
Pages :
Book Description
AlGaN/GaN HEMTs Reliability. Degradation Modes and Analysis
Author: Ponky IvoPublisher: Cuvillier
ISBN: 9783954042593
Category : Gallium nitride
Languages : en
Pages : 0
Book Description
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.
Power GaN Devices
Author: Matteo MeneghiniPublisher: Springer
ISBN: 3319431994
Category : Technology & Engineering
Languages : en
Pages : 383
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.
Reliability Studies of AlGaN/GaN HEMTs with High-k Dielectrics
Author: Current Instabilities, Passivation Effects and Other Reliability Aspects in AlGaN/GaN HEMTs for Microwave Applications
Author: Fabiana RampazzoInvestigation of Electrical Bias, Mechanical Stress, Temperature and Ambient Effect on AlGaN/GaN Hemt Time-Dependent Degradation
Author: Amit GuptaPublisher:
ISBN:
Category :
Languages : en
Pages : 143
Book Description
AlGaN/GaN HEMT technology is promising for RF and high power applications. However commercial usability of this technology is currently hindered because of its limited electrical reliability which still remains a major concern. AlGaN/GaN HEMTs have been shown to degrade irreversibly under typical device operation and there is widespread disagreement on the underlying fundamental physics for the observed device degradation. Electrical degradation in AlGaN/GaN HEMTs due to DC stressing is studied typically by performing electrical step stress tests and a critical voltage is determined. Device degradation is characterized by changes measured in electrical parameters, such as increase in Rs and RD, decrease in IDsat, decrease in gm, Vt shift and sub-threshold change. The widely accepted theory attributes such degradation to the inverse piezoelectric effect. Electric field due to applied bias generates biaxial tensile stress which together with intrinsic stress from lattice mismatch increases the elastic energy of AlGaN layer.
Noise in Nanoscale Semiconductor Devices
Author: Tibor GrasserPublisher: Springer Nature
ISBN: 3030375005
Category : Technology & Engineering
Languages : en
Pages : 724
Book Description
This book summarizes the state-of-the-art, regarding noise in nanometer semiconductor devices. Readers will benefit from this leading-edge research, aimed at increasing reliability based on physical microscopic models. Authors discuss the most recent developments in the understanding of point defects, e.g. via ab initio calculations or intricate measurements, which have paved the way to more physics-based noise models which are applicable to a wider range of materials and features, e.g. III-V materials, 2D materials, and multi-state defects. Describes the state-of-the-art, regarding noise in nanometer semiconductor devices; Enables readers to design more reliable semiconductor devices; Offers the most up-to-date information on point defects, based on physical microscopic models.
Advanced Device Reliability Study of GaN HEMTs Using Low Frequency Noise Spectroscopy
Author: Hemant P. RaoPublisher:
ISBN:
Category :
Languages : en
Pages : 93
Book Description
The channel is found be to immune to the stress. The role of impurity diffusion as a precursor to catastrophic degradation is also pointed out. Key bias points are identified which result in permanent trap creation at the AlGaN/GaN channel interface. The role of hot-carriers as a failure mechanism is discussed by measuring electron temperature profiles in the channel. Finally degradation of the gate stack under RF overdrive stress is studied and the activation energy and the trap location of a point defect center in the AlGaN barrier is extracted.