What is a semiconductor?
A semiconductor is a substance that has specific electrical properties that are used to serve as a foundation for computers and other electronic devices. semiconductor technology is used in Transistors, diodes, thyristors, field effect transistors, integrated circuits, and many more electronic components.
Examples of Semiconductors
silicon and germanium are some of the most commonly used semiconductors. Mainly Silicon is used in electronic circuit fabrication
What are Holes and Electrons?
Holes are the positively charged electric charge carriers while electrons are the negatively charged particles. Both electrons and holes are equal in magnitude but opposite in polarity. The mobility of electrons is higher than that of the holes because of their different band structures and scattering mechanisms. Electrons travel in the conduction band whereas holes travel in the valence band.
What is Conduction Band and Valence Band?
The energy band involving the energy levels of conductive electrons is known as the conductance band. It is the lowest unoccupied band that includes the energy levels of positive or negative charge carriers. It has conducting electrons resulting in the flow of current. The energy band involving the energy levels of valence electrons is known as the valence band. It is the highest occupied energy band.
What is Fermi Level in Semiconductors?
Fermi level is present between the valence and conduction bands. It is the highest occupied molecular orbital at absolute zero. It is denoted by EF
Types of Semiconductors
Semiconductors can be divided into two types
- Intrinsic Semiconductor
- Extrinsic Semiconductor
The properties of Semiconductors are
- The size is small.
- The conductivity of the semiconductors increases when impurities are added.
- Semiconductor resistivity is higher than conductors but lesser than insulators.
- We can use semiconductors in microelectronics.
- At zero kelvin, semiconductors behave as insulators. As the temperature is increased it works as a conductor.
- The resistance of semiconductor materials decreases with the increase in temperature(Not applicable for Lower Technology nodes