03-08-2012, 04:29 PM
PHYSICAL ELECTRONICS ECX 5239
1PHYSICAL ELECTRONICS.ppt (Size: 840 KB / Downloads: 64)
Introduction
What is a semiconductor ?
Introduction about Current density, Resistivity, Conductivity, Drift velocity, Mobility.
How to solve my problems according to above equations.
What Is a Semiconductor?
Many materials, such as most metals, allow electrical current to flow through them
These are known as conductors
Materials that do not allow electrical current to flow through them are called insulators
A material whose properties are such that it is not quite a conductor, not quite an insulator
That material called as semiconductor.
Semiconductors can be Conductors
An impurity, or element like arsenic, has 5 valence electrons.
we remove a silicon atom from the crystal lattice and replace it with a arsenic atom.
We now have an electron that is not bonded – it is thus free for conduction.
This type of silicon is called n-type .