Semiconductors
In solid-state electronics, using the proper types and amounts of dopants in semiconductors is what produces the p-type semiconductors and n-type semiconductors that are essential for making transistors and diodes.
The addition of a dopant to a semiconductor, known as doping, has the effect of shifting the Fermi levels within the material. This results in a material with predominantly negative (n-type) or positive (p-type) charge carriers depending on the dopant variety. Pure semiconductors that have been altered by the presence of dopants are known as extrinsic semiconductors . Dopants are introduced into semiconductors in a variety of techniques: solid sources, gases, spin on liquid, and ion implanting. See ion implantation, surface diffusion, and solid sources footnote.
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