Semiconductor Physics
Semiconductors are materials.
They have electrical conductivity between conductors and insulators.
Silicon and germanium are common examples.
The behavior depends on electrons and holes.
Electrons carry negative charge.
Holes act as positive charge carriers.
Both are vital for current flow.
At absolute zero, semiconductors act like insulators.
At higher temperatures, electrons gain energy.
They jump from the valence band to the conduction band.
This creates free carriers for conduction.
Semiconductors are classified as intrinsic and extrinsic.
Intrinsic means pure material.
Extrinsic means doped with impurities.
Doping increases conductivity.
n-type uses extra electrons.
p-type uses extra holes.
The p-n junction is fundamental.
It is the base of diodes and transistors.
Current flows in one direction in a diode.
Transistors amplify signals and switch circuits.
Semiconductors enable microchips.
They power computers, mobiles, and electronics.
They are the heart of modern technology.
Light interaction is also important.
LEDs emit light when current flows.
Solar cells convert light into electricity.
Semiconductor physics connects theory with application.
It explains quantum mechanics, band theory, and device design.
It drives innovation in nanotechnology and quantum computing.