Discussion Questions are meant to be completed when they are reached in the reading, before continuing.  Getting the "correct" answer to Discussion Questions is not important.  Instead, the purpose of Discussion Questions is to address the issues, start you thinking about the material, and identify your preconceptions.  Completing these assignments before continuing with the reading will aid you greatly in the learning process.
 

Have you heard the word "semiconductor" used?  In what context?  What roles do semiconductors play in information technology? List some materials that might be classified as semiconductors.  How many can you think of? How might a semiconductor differ from a conductor or an insulator?  What might be some similarities? Niels Bohr determined in the early part of the 20th century that atoms can exist only in certain energy states.  In solids, we discuss energy "bands" rather than energy states.  What might be the difference between the energy states of a single atom and the energy bands in a solid?  Why do energy states become energy bands when atoms bond to form solids?

A silicon wafer containing chips.  Features on the wafer are about 2 microns in size.

 

Before we can understand the properties of semiconductors, we need to understand energy states in atoms and bands in solids.  Go to the next page to learn about energy states in atoms!