Semiconductor Diodes

The p-n junction

  1. We can produce a single crystal with p-type semiconductor on one side and n-type on the other side as shown in figure above.
  2. The border where the p-type and the n-type region meet is called the p-n junction.

Depletion Layer and Junction Voltage

  1. At the p-n junction, electrons from the n-type semiconductor will be attracted to the holes in the p-type semiconductor.
  2. As a result, the holes and the electrons at the p-n junction disappear, forming a layer called “depletion layer”.
  3. At the same time, the p-type semiconductor becomes more negative whereas the n-type semiconductor becomes more positive.
  4. This will result a potential difference across the p-n junction. This potential difference is called the junction voltage (or the barrier voltage).
  5. The junction voltage will prevent the charge carrier from flowing across the depletion layer.

Recommended Videos

Formation and Properties of Junction Diode - Physics
This is a physics video for Grade 11-12 students about p-n junction diode, its properties, characteristics and uses. The combination of p-type and n-type semiconductors results in a junction. When a p-type semiconductor is joined with n-type semiconductor, the resultant junction formed is called a p-n junction diode.