VLSI-Design of Non-Volatile Memories

The electronics and information technology revolution continues, but it is a critical
time in the development of technology. Once again, we stand on the brink of a
new era where emerging research will yield exciting applications and products
destined to transform and enrich our daily lives! The potential is staggering and
the ultimate impact is unimaginable, considering the continuing marriage of technology
with fields such as medicine, communications and entertainment, to name
only a few.
But who will actually be responsible for transforming these potential new products
into reality? The answer, of course, is today’s (and tomorrow’s) design engineers!
The design of integrated circuits today remains an essential discipline in support
of technological progress, and the authors of this book have taken a giant step
forward in the development of a practice-oriented treatise for design engineers
who are interested in the practical, industry-driven world of integrated circuit design.
The authors, Giovanni Campardo and Rino Micheloni, are very well qualified
to effectively address this challenging objective. Both have a solid track record of
leading design activities at the STMicroelectronics Flash Division. I should
probably mention at this point my association with and knowledge of the accomplishments
of these authors. In April 2003, they published a unique Special Issue
on the subject of Flash Memories for the Proceedings of the IEEE, the journal for
which I am Managing Editor. Therefore, I have firsthand knowledge of their approach
to the development of very well crafted technical material.
In addition, a third member of the author team, David Novosel, has provided
invaluable assistance, particularly in the translation efforts on this material. David
is President and founder of Intelligent Micro Design, Inc. which specializes in the
design of custom memories and analog circuits, which is located in Pittsburgh,
PA.
This book is intended for Electrical Engineering graduates who want to enter
into the integrated circuit design world. Nonvolatile memories, in many cases, are
treated as an example to explain general design concepts (basic circuits, layout,
design flow, etc.). Practical illustrative examples of nonvolatile memories, including
flash types, are showcased to give insightful examples of the design approaches
that are discussed. The authors introduce the key nonvolatile memories
design issues in the first section and they discuss the various functions and capabilities
of these memories; much of these discussions are based on their recently
published Special Issue on the subject of Flash memories.After a complete review of the general design issues, the authors begin to focus
on the important concepts that should be understood. For example, they introduce
MOS Process and briefly review the CMOS building blocks and the four available
components. In the next section the authors describe Memory cell operations including
Read and Erase operations, as well as coverage of software and program
issues.
Comprehensive sections on Design Building Blocks, Integrated circuits layout,
and Matrix architecture are included. They explore in some depth Input buffers,
Output Buffers Decoders and Program and Erase operations circuitry. They discuss
the subjects of Timers and Read operation sensing techniques.
Two sections deal with quality and dependability-related issues, and cover the
subjects of Redundancy and Test Modes. Coverage is also provided on ESD &
latch-up issues as well as Embedded Flash algorithms.
A collection of photos is included to make the reader familiar with silicon aspects.
Throughout all parts of this book, the authors have taken a practical and applications-
driven point of view, providing a comprehensive and easily understood
approach to all the concepts discussed.
I greatly appreciate the very kind invitation of the authors to submit these
words of introduction for their exciting new book. I wish them continued success
in their latest publishing enterprise, but more importantly I hope that all who are
reading these words will derive knowledge and understanding from the sincere
and dedicated efforts of the authors.