PHILOSOPHY AND GOALS
The purpose of this text is to provide a basis for understanding the characteristics,operation, and limitations of semiconductor devices. In order to gain this understanding,it is essential to have a thorough knowledge of the physics of the semiconductor material. The goal of this book is to bring together the fundamental physics of the semiconductor material and the semiconductor device physics.
Since the objective of this text is to provide an introduction to the theory of semiconductor devices, there is a great deal of advanced theory that is not considered. This material is found is more advanced texts. There are occasions in the text where equations and relationships are simply stated with no or very little derivation. Again, the details are found in more advanced texts. However, the author feels that there is enough mathematics included to provide a good foundation for the basic understanding of semiconductor devices in this first course.
PREREQUISITES
This text is intended for junior and senior undergraduates in electrical engineering. The prerequisites for understanding the material are college mathematics, up to and including differential equations, and college physics, including an introduction to modern physics and electrostatics. Prior completion of an introductory course in electronic circuits is helpful, but not essential.
ORDER OF PRESENTATION
Each instructor has a personal preference for the order in which the course material is presented. The order of presentation of topics in this text is somewhat different compared to many semiconductor textbooks. Chapters 1—4 cover the basic physics of the semiconductor material and contain topics normally covered initially in any semiconductor device course. Chapter 5 discusses the electrostatics of the pn and Schottky junctions. This material is necessary and sufficient for the understanding of the MOS transistor presented in Chapters 6 and 7. There are two reasons for discussing the MOS transistor at this point. First, since the MOS transistor is fundamental to integrated circuits, this material is presented early enough in the course so that it doesn’t get “short changed,” as it might when covered at the end of a course. Second, since a “real” semiconductor device is discussed fairly early in the course, the reader may have more motivation to continue studying this course material.
After the MOS transistor is presented, the nonequilibrium characteristics of the semiconductor material is presented in Chapter 8 and then the forward-biased pn junction and Schottky diodes are discussed in Chapter 9. The bipolar transistor is presented in Chapter 10. Chapter 11 covers additional devices such as junction fieldeffect transistors and thyristors. Finally, optical devices are discussed in Chapter 12.
One possible disadvantage to this order of presentation is that the discussion of the pn junction is “interrupted.” However, the author feels that a “just-in-time” approach is justified. Some discussion of the pn junction is necessary before presenting the MOS transistor. However, if the entire discussion of the pn junction, including the discussion of nonequilibrium excess carriers, took place before the MOS transistor, then much of the knowledge gained of forward-biased pn junctions would be lost by the reader by the time the bipolar transistor is discussed.
The following table lists the textbook approach to the order of presentation of topics. Unfortunately, because of time constraints, every topic in every chapter cannot be covered in a one-semester course. | | Textbook Approach | | Chapter 1 | | Crystal Structure | | Chapter 2 | | Selected topics from quantum mechanics and theory of solids | | Chapter 3 | | Semiconductor material physics | | Chapter 4 | | Transport phenomena | | Chapter 5 | | Electrostatics of the pn junction | | Chapter 6 | | The MOS transistor | | Chapter 7 | | Selected topics for advanced MOSFETs | | Chapter 8 | | Selected topics from nonequilibrium semiconductor physics | | Chapter 9 | | The pn junction diode | | Chapter 10 | | The bipolar transistor | | Chapter 11 | | Selected topics from other devices | | Chapter 12 | | Selected topics from optical devices |
For those instructors who prefer the classical approach and wish to cover the bipolar transistor before the MOS transistor, the following table lists the order of presentation. The chapters are written so that this order of presentation is very plausible.
| | Classical Approach | | Chapter 1 | | Crystal Structure | | Chapter 2 | | Selected topics from quantum mechanics and theory of solids | | Chapter 3 | | Semiconductor material physics | | Chapter 4 | | Transport phenomena | | Chapter 8 | | Selected topics from nonequilibrium semiconductor physics | | Chapter 5 | | Electrostatics of the pn junction | | Chapter 9 | | The pn junction diode | | Chapter 10 | | The bipolar transistor | | Chapter 6 | | The MOS transistor | | Chapter 7 | | Selected topics for advanced MOSFETs | | Chapter 11 | | Selected topics from other devices | | Chapter 12 | | Selected topics from optical devices |
USE OF THE BOOK
The text is intended for a one-semester course at the junior or senior
level. As with most textbooks, there is more material than can be conveniently covered in
one semester; this enables each instructor some flexibility in designing the course to
his or her own specific needs. At the end of several chapters, there is a section dealing with fabrication technology.
In Chapter 1, this topic deals with the growth of semiconductor materials and
the oxidation process. In Chapter 3, this topic deals with the introduction of specific
impurities into the semiconductor by either diffusion or ion implantation. In later
chapters, this topic deals with the fabrication of specific devices. In each case, the
fabrication discussion is relatively short and intended only to give the reader a basic
understanding of the fabrication technology. These sections, as well as a few other
sections in the text, are denoted by the symbol ∑ in front of the section heading. The
symbol ∑ shows that reading these sections will aid in the total summation of the understanding of semiconductor devices. However, a basic understanding of semiconductor
device physics can be accomplished without studying these sections in detail during this first introductory course. FEATURES OF THE BOOK
- Preview section: A preview section introduces each chapter. This preview links the chapter to previous chapters and states the chapter’s goals, that is, what the reader should gain from the chapter.
- Historical and Present-Day Insights: A Historical Insight section relates the chapter material to a few historical events and a Present-Day Insight section relates the chapter material to current research and manufacturing events.
- Icon: ∑, indicates sections that are to be read for understanding to increase the total summation of knowledge of semiconductor devices. However, a detailed study of these sections is not required during this first introductory course.
- Key terms in the margin: Key terms are listed in the margin of the text. Quickly finding a key term adjacent to the text in which the material is discussed should aid the student in reviewing the material.
- Examples: There are a liberal number of examples given in the text to reinforce the theoretical concepts being developed. These examples contain all the details of the analysis or design, so the reader does not have to fill in missing steps.
- Exercise problems: An exercise problem is given after each example. These exercises are similar in scope to the preceding example. The ability to solve these exercise problems should be an indication as to whether the student has mastered the previous material. Answers to these problems are given.
- Test Your Understanding exercises: At the end of major sections, additional exercise problems are given. These exercise problems tend to more comprehensive than the exercise problems given after each example. Answers to these problems are also given.
- Summary: A summary section follows the text of each chapter. This section summarizes the overall results derived in the chapter and reviews the basic concepts developed.
- Checkpoint: A checkpoint section follows the Summary section. This section states the goals that should have been met and states the abilities the reader should have gained. The Checkpoints will help assess progress before moving to the next chapter.
- Review questions: A list of review questions is included at the end of each chapter. These questions serve as a self-test to help the reader determine how well the concepts developed in the chapter have been mastered.
- End-of-chapter problems: A substantial number of problems are provided at the
end of each chapter, organized according to the subject of each section. Answers to a selected number are provided in Appendix F.
- Answers to selected problems: Answers to selected problems are given in Appendix F. Knowing the answer to a problem can aid and reinforce the problem solving.
|
2006 McGraw-Hill Higher Education