Yuan Taur - Fundamentals of Modern VLSI Devices

Learn the basic properties and designs of modern VLSI devices, as well as the factors affecting performance, with this thoroughly updated second edition. The first edition has been widely adopted as a standard textbook in microelectronics in many major US universities and worldwide. The internationally renowned authors highlight the intricate interdependencies and subtle tradeoffs between various practically important device parameters. An in-depth discussion of device scaling and scaling limits of CMOS and bipolar devices is also provided. Equations and parameters provided are checked continuously against the reality of silicon data, making the book equally useful in practical transistor design and in the classroom.

New to this edition:

• Every chapter has been updated to include the latest developments, such as MOSFET scale length theory, high-field transport models, and SiGe-base bipolar devices.
• Two new chapters cover read and write operations of commonly used SRAM, DRAM, and non-volatile memory arrays, as well as silicon-on-insulator (SOI) devices, including advanced devices of future potential.
• More useful appendices : The number has doubled from 9 to 18, covering areas such as spatial variation of quasi-Fermi potentials, image-force-induced barrier lowering, and power gain of a two-port network.
• New homework exercises at the end of every chapter engage students with real-world problems and test their understanding.

It has been fifty years since the invention of the bipolar transistor, more than forty years since the invention of the integrated-circuit (IC) technology, and more than thirty-five years since the invention of the MOSFET. During this time, there has been a tremendous and steady progress in the development of the IC technology with a rapid expansion of the IC industry. One distinct characteristic in the evolution of the IC technology is that the physical feature sizes of the transistors are reduced continually over time as the lithography technologies used to define these features become available. For almost thirty years now, the minimum lithography feature size used in IC manufacturing has been reduced at a rate of 0.7 every three years. In 1997, the leading-edge IC products have a minimum feature size of 0.25 m.

The basic operating principles of large and small transistors are the same. However, the relative importance of the various device parameters and performance factors for transistors of the 1- m and smaller generations is quite different from those for transistors of larger-dimension generations. For example, in the case of CMOS, the power-supply voltage was lowered from the standard 5 V, starting with the 0.6- to 0.8- m generation. Since then CMOS power supply voltage has been lowered in steps once every few years as the device physical dimensions are reduced. At the same time, many physical phenomena, such as short-channel effect and velocity saturation, which are negligible in large-dimension MOSFETs, are becoming more and more important in determining the behavior of MOSFETs of deep-submicron dimensions. In the case of bipolar devices, breakdown voltage and base-widening effects are limiting their performance, and power dissipation is limiting their level of integration on a chip. Also, the advent of SiGe-base bipolar technology has extended the frequency capability of small-dimension bipolar transistors into the range previously reserved for GaAs and other compound-semiconductor devices.

The purpose of this book is to bring together the device fundamentals that govern the behavior of CMOS and bipolar transistors into a single text, with emphasis on those parameters and performance factors that are particularly important for VLSI (very-large-scale-integration) devices of deep-submicron dimensions. The book starts with a comprehensive review of the properties of the silicon material, and the basic physics of pn junctions and MOS capacitors, as they relate to the fundamental principles of MOSFET and bipolar transistors. From there, the basic operation of MOSFET and bipolar devices, and their design and optimization for VLSI applications are developed. A great deal of the volume is devoted to in-depth discussions of the intricate interdependence and subtle tradeoffs of the various device parameters pertaining to circuit performance and manufacturability. The effects which are particularly important in small-dimension devices, e.g., quantization of the two-dimensional surface inversion layer in a MOSFET device and the heavy-doping effect in the intrinsic base of a bipolar transistor, are covered in detail. Also included in this book are extensive discussions on scaling and limitations to scaling of MOSFET and bipolar devices.