TABLE OF CONTENTS Almost all common electronic devices use semiconductors. Yet, many readers might not be able to answer the question, What is a semiconductor? Similarly, they might not know the most basic science and technology of this important class of materials. In the spirit of trying to build understanding from the basics, this chapter introduces the reader to semiconductors. The basic question, What is a semiconductor? will be addressed first. In practice, pure semiconductors are not as technologically useful as doped semiconductors, semiconductors containing controlled amounts of impurities. Thus, we will ask:
What is a semiconductor?
What is a doped semiconductor?
How are semiconductors doped?
Why are semiconductors doped?
How are semiconductors used to make electronic devices?
What are some electronic devices?
How do semiconductor devices work?
Semiconductors are of great importance to our everyday life. Almost every appliance, electronic entertainment device, and automobile contains semiconductors, in the form of transistors, that are part of integrated circuits that are part of more complex systems. While the details of semiconductor technology are very complex, a basic understanding of what semiconductors are and how they are used is not too complex and is vitally important to our later understanding of the computer.
The macroscopic behavior of semiconductors may be distinguished from metals and insulators in two ways. First, as the name implies, the (electrical) conductivity, or ability to conduct electricity, at room temperature is between that of metals (much higher electrical conductivity) and insulators (much lower conductivity). It is important...
