Hfo2 Based Gate Dielectrics For Nanoscale Mosfets

"The book comprehensively covers all the current and the emerging areas of the physics and the technology of high permittivity gate dielectric materials, including, topics such as MOSFET basics and characteristics, hafnium-based gate dielectric materials, Hf-based gate dielectric processing, metal gate electrodes, flat-band and threshold voltage tuning, channel mobility, high-k gate stack degradation and reliability, lanthanide-based high-k gate stack materials, ternary hafnia and lanthania based high-k gate stack films, crystalline high-k oxides, high mobility substrates, and parameter extraction. Each chapter begins with the basics necessary for understanding the topic, followed by a comprehensive review of the literature, and ultimately graduating to the current status of the technology and our scientific understanding and the future prospects." .

In this work, the reliability of HfO2 (hafnium oxide) with poly gate and dual metal gate electrode (Ru–Ta alloy, Ru) was investigated. Hard breakdown and soft breakdown, particularly the Weibull slopes, were studied under constant voltage stress. Dynamic stressing has also been used. It was found that the combination of trapping and detrapping contributed to the enhancement of the projected lifetime. The results from the polarity dependence studies showed that the substrate injection exhibited a shorter projected lifetime and worse soft breakdown behavior, compared to the gate injection. The origin of soft breakdown (first breakdown) was studied and the results suggested that the soft breakdown may be due to one layer breakdown in the bilayer structure (HfO2/SiO2: 4 nm/4 nm). Low Weibull slope was in part attributed to the lower barrier height of HfO2 at the interface layer. Interface layer optimization was conducted in terms of mobility, swing, and short channel effect using deep submicron MOSFET devices.

In this work, the reliability of HfO2 (hafnium oxide) with poly gate and dual metal gate electrode (Ru-Ta alloy, Ru) was investigated. Hard breakdown and soft breakdown, particularly the Weibull slopes, were studied under constant voltage stress. Dynamic stressing has also been used. It was found that the combination of trapping and detrapping contributed to the enhancement of the projected lifetime. The results from the polarity dependence studies showed that the substrate injection exhibited a shorter projected lifetime and worse soft breakdown behavior, compared to the gate injection. The origin of soft breakdown (first breakdown) was studied and the results suggested that the soft breakdown may be due to one layer breakdown in the bilayer structure (HfO2/SiO2: 4 nm/4 nm). Low Weibull slope was in part attributed to the lower barrier height of HfO2 at the interface layer. Interface layer optimization was conducted in terms of mobility, swing, and short channel effect using deep submicron MOSFET devices.

Comprehensive reference on the fundamental principles and basic physics dictating metal–oxide–semiconductor field-effect transistor (MOSFET) operation Advanced Nanoscale MOSFET Architectures provides an in-depth review of modern metal–oxide–semiconductor field-effect transistor (MOSFET) device technologies and advancements, with information on their operation, various architectures, fabrication, materials, modeling and simulation methods, circuit applications, and other aspects related to nanoscale MOSFET technology. The text begins with an introduction to the foundational technology before moving on to describe challenges associated with the scaling of nanoscale devices. Other topics covered include device physics and operation, strain engineering for highly scaled MOSFETs, tunnel FET, graphene based field effect transistors, and more. The text also compares silicon bulk and devices, nanosheet transistors and introduces low-power circuit design using advanced MOSFETs. Additional topics covered include: High-k gate dielectrics and metal gate electrodes for multi-gate MOSFETs, covering gate stack processing and metal gate modification Strain engineering in 3D complementary metal-oxide semiconductors (CMOS) and its scaling impact, and strain engineering in silicon–germanium (SiGe) FinFET and its challenges and future perspectives TCAD simulation of multi-gate MOSFET, covering model calibration and device performance for analog and RF applications Description of the design of an analog amplifier circuit using digital CMOS technology of SCL for ultra-low power VLSI applications Advanced Nanoscale MOSFET Architectures helps readers understand device physics and design of new structures and material compositions, making it an important resource for the researchers and professionals who are carrying out research in the field, along with students in related programs of study.

This volume explores and addresses the challenges of high-k gate dielectric materials, one of the major concerns in the evolving semiconductor industry and the International Technology Roadmap for Semiconductors (ITRS). The application of high-k gate dielectric materials is a promising strategy that allows further miniaturization of microelectronic components. This book presents a broad review of SiO2 materials, including a brief historical note of Moore’s law, followed by reliability issues of the SiO2 based MOS transistor. It goes on to discuss the transition of gate dielectrics with an EOT ~ 1 nm and a selection of high-k materials. A review of the various deposition techniques of different high-k films is also discussed. High-k dielectrics theories (quantum tunneling effects and interface engineering theory) and applications of different novel MOSFET structures, like tunneling FET, are also covered in this book. The volume also looks at the important issues in the future of CMOS technology and presents an analysis of interface charge densities with the high-k material tantalum pentoxide. The issue of CMOS VLSI technology with the high-k gate dielectric materials is covered as is the advanced MOSFET structure, with its working structure and modeling. This timely volume will prove to be a valuable resource on both the fundamentals and the successful integration of high-k dielectric materials in future IC technology.

Issues relating to the high-K gate dielectric are among the greatest challenges for the evolving International Technology Roadmap for Semiconductors (ITRS). More than just an historical overview, this book will assess previous and present approaches related to scaling the gate dielectric and their impact, along with the creative directions and forthcoming challenges that will define the future of gate dielectric scaling technology.