Electronic Devices and Integrated Circuits

1

Physics of Semiconductors

1.1 Introduction

An understanding of the electrical properties of semiconductors is a prerequisite to the study of electronic devices, both bipolar and Metal Oxide Semiconductor (MOS). This chapter explains the electrical behaviour of a semiconductor.

Materials are grouped under the following three categories depending on their ability to conduct electricity:

• Conductors (silver, copper, aluminum, etc.)
• Semiconductors (germanium, silicon, aluminum-galium-arsenide, etc.)
• Insulators (glass, ceramic, bakelite, rubber, air, element sulphur).

1.1.1 Conductors

Metals such as silver, copper, aluminum, etc. that contain free electrons which are responsible for electrical conduction through them are called conductors. The ...