PN Junction – Semiconductor electronics for class 12 physics students.
GET INSTANT HELP FROM EXPERTS!
- Looking for any kind of help on your academic work (essay, assignment, project)?
- Want us to review, proofread or tidy up your work?
- Want a helping hand so that you can focus on the more important tasks?
Hire us as project guide/assistant. Contact us for more information
When P-Types and N-Types semiconductor are joined together such that crystal structure remains continuous, a p-n junction is formed. It is formed by adding excessive impurities to n-type semiconductor or donor impurities to a p-type semiconductor.
When PN junction is formed, both material will find their fermi-levels nonaligned. As diffusion takes place across the junction; the holes and electrons combine to neutralize each other at the junction and produce a free space called deflection layer.
At the junction, due to migration of a few holes from p-types to n-types region, the negative immobile electrons are produced in P region and positive immobile ions are produced in N region. Under equilibrium, conducts a potential barrier is developed which prevents further diffusion.
Procedure:
- Connect the circuit with the diode forward biased.
- Switch on power supply.
- Increase voltage across diode in steps of 0.05v.
- Note the corresponding current ammeter.
- Record and tabulate the observation
- Plot V/I graph characteristics with voltage on x and current on y axis.
- Find slope and calculate dynamic resistance.
Leave a Reply