Crystal Properties and Growth of Semiconductors
Crystal Properties and Growth of Semiconductors
In studying solid state electronic devices we are interested primarily in the electrical behavior of solids. However, we shall see in later chapters that the transport of charge through a metal or a semiconductor depends not only on the properties of the electron but also on the arrangement of atoms in the solid. In the first chapter we shall discuss some of the physical properties of semiconductors compared with other solids, the atomic arrangements of var- ious materials, and some methods of growing semiconductor crystals. Topics such as crystal structure and crystal growth technology are often the subjects of books rather than introductory chapters; thus we shall consider only a few of the more important and fundamental ideas that form the basis for under- standing electronic properties of semiconductors and device fabrication.
Semiconductors are a group of materials having electrical conductivities in- termediate between metals and insulators. It is significant that the conduc- tivity of these materials can be varied over orders of magnitude by changes in temperature, optical excitation, and impurity content. This variability of electrical properties makes the semiconductor materials natural choices for electronic device investigations.
Semiconductor materials are found in column IV and neighboring columns of the periodic table (Table 1-1).The column IV semiconductors, sil- icon and germanium, are called elemental semiconductors because they are composed of single species of atoms. In addition to the elemental materials, compounds of column III and column V atoms, as well as certain combina- tions from II and VI, and from IV, make up the compound semiconductors.
1.1 SEMICONDUCTOR MATERIALS
2
Chapter 1
As Table 1-1 indicates, there are numerous semiconductor materials. As we shall see, the wide variety of electronic and optical properties of these semicon- ductors provides the device engineer with great
In studying solid state electronic devices we are interested primarily in the electrical behavior of solids. However, we shall see in later chapters that the transport of charge through a metal or a semiconductor depends not only on the properties of the electron but also on the arrangement of atoms in the solid. In the first chapter we shall discuss some of the physical properties of semiconductors compared with other solids, the atomic arrangements of var- ious materials, and some methods of growing semiconductor crystals. Topics such as crystal structure and crystal growth technology are often the subjects of books rather than introductory chapters; thus we shall consider only a few of the more important and fundamental ideas that form the basis for under- standing electronic properties of semiconductors and device fabrication.
Semiconductors are a group of materials having electrical conductivities in- termediate between metals and insulators. It is significant that the conduc- tivity of these materials can be varied over orders of magnitude by changes in temperature, optical excitation, and impurity content. This variability of electrical properties makes the semiconductor materials natural choices for electronic device investigations.
Semiconductor materials are found in column IV and neighboring columns of the periodic table (Table 1-1).The column IV semiconductors, sil- icon and germanium, are called elemental semiconductors because they are composed of single species of atoms. In addition to the elemental materials, compounds of column III and column V atoms, as well as certain combina- tions from II and VI, and from IV, make up the compound semiconductors.
1.1 SEMICONDUCTOR MATERIALS
2
Chapter 1
As Table 1-1 indicates, there are numerous semiconductor materials. As we shall see, the wide variety of electronic and optical properties of these semicon- ductors provides the device engineer with great