Doping is introduced to tune the bandgap of semiconductors and both add charge carriers - n-doping adds electrons to the conduction band (e.g. arsenic as dopant), more accurately adding an electron donator level with a very small bandgap in relation to the conduction band. Going the other way, p-doping removes electrodes (e.g. boron as dopant), really by adding an electron acceptor level with a very small bandgap to the valence band, i.e. "adds holes."
Unless there is any doping in the semiconductor (intrinsic semiconductor), it cannot conduct electricity.
Please go through "why defect is important in semiconductors?"
With specific dopants, a semiconductor behaves as n-type (holes minority carriers) or p-type (electrons minority carriers).
The dopants create allowed shallow states in the bandgap. When the dopant density is high, the dopant state generates a band. If the band is either close to valence band or conduction band, the bandgap reduces.
You may go through the attached link for details.
https://www.halbleiter.org/en/fundamentals/doping/
Dear brothers,
Thank you very much for all clarifications.
Regards,
Edge position of semiconductor band gap can be altered by doping with various metallic or non-metallic elements like Pt,Pd,Au,Cu,Fe Al, In, Ga,Li, Na, K ,Ag,….. As the quantity and the variety of dopant are change, the crystallinity ,surface area, transmittance, conductivity as well as optical band gap may be change. You can get n-type semiconductor on doping with electron-rich atoms like N,and doping with electron-deficient atoms like B, you can get a p-type semiconductor.
- Badges
- Science topic
- Similar topics
- Physical Sciences
- Materials Science