PN junction diode

Thread Starter

ee student

Joined Nov 6, 2006
i am new here, and i just want to ask, if i have a PN junction doped with Na=2*10^17 on the p side
how to calculate the hole density/
thank you


Joined Nov 17, 2003
I like some others may be a touch confused here; Na is the volume density of donors (in this case holes) per unit volume.

Are you trying to calculate the total charge on the p-side?

If so:

Q = q*Na*wp


Q = total charge
q = 1.6e-19
Na = 2e17
Wp = the width of the p-side of the PN junction.

What is PN Junction (Diode):
A PN Junction Diode is a two-terminal semiconductor device. It’s made up from a small piece of semiconductor material (usually Silicon), it allows the electric current to flow in one direction while opposes the current in other direction. In the Forward Bias, the diode allows the current to flow in uni-direction. On the other hand, when the diode is reverse biased it opposes the electric current to flow. A PN Junction Diode is a semiconductor device with two opposite region such as (P-type region and N-type region).

  • The P-region is called as the anode and is connected to a positive terminal of a battery and it has Holes in majority carrier and electrons in minority carrier.
  • The N-region is called as the cathode and is connected to the negative terminal of a battery and it has Electrons as a Majority carrier while holes as Minority carrier.
When the P-type semiconductor material is joined with the N-type semiconductor material, a P-N Junction is formed, hence resulting P-N Junction is also called as a P-N Junction Diode.
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