Semiconductor Physics

What is Atomic Bonds and Types? Whether a material is a conductor, a semiconductor, or an insulator depends largely upon what happens to the outer-shell electrons when the atoms bond themselves together to form a solid. Atomic bonds arc of two types viz. primary (or chemical) bonds and secondary (or molecular) bonds. Primary bonds are […]

Drift Current and Diffusion Current in Semiconductor: The two basic processes which cause electrons and holes to move in a semiconductor are : drift, which is the movement caused by electric fields, and diffusion, which is the flow caused by variations in the concentration, i.e., concentration gradients. Such gradients can be caused by a non-homogeneous

Energy Band Diagram of Semiconductors, Insulators and Metals: Energy Band Diagram of Semiconductors, Insulators and Metals – As discussed earlier, the electrons of an isolated atom are acted upon only by the forces within that atom. However, when atoms are brought together, as in a solid, the electrons come under the influence of forces from

Energy Band Theory of Crystals: Energy Band Theory of Crystals – As discussed above, it is revealed that most metals and semiconductors are crystalline in structure and a crystal is made up of a space array of atoms or molecules (strictly speaking, ions) in regular repetition in three dimensions of some fundamental structural unit. For

What is Crystalline Structure? What is Crystalline Structure? – Solids are characterized by incompressibility, rigidity and mechanical strength. This indicates that the molecules, atoms or ions that make up a solid are closely packed, i.e., they are held together by strong forces and cannot move at random. On the contrary, gases are characterized by a

Compound Semiconductor Materials: Most of the compound semiconductor materials are formed from the combinations of group III and group V elements. A portion of the periodic table listing the more common semiconductors is given in Table 6.2. A list of some semiconductor materials is given in Table 6.3. Two element compounds are called the binary