Why Don't Electrons Flow from P-type to N-type in a Reverse Biased PN Junction?

[Dembie]

[Mentor's Note: Thread moved and edited by mentor.]

Sorry I am new and I had problems creating the thread. But I will post my question here:-D. So in reverse biased pn junction the width of the depletion layer increases. But on the N side a large positive charge from the donnor ions is building. Why it doesn't attract electrons from the acceptor ions? Why electrons doesn't flow from the P type through the N type and into the positive terminal of Vcc?

 

[AndyW]

Hi there,

Thank you for your question. The behavior of electrons in a reverse biased pn junction is governed by the electric field present in the depletion layer. This electric field is created by the excess of positive charges on the p-side and negative charges on the n-side.

In the reverse biased condition, the electric field created is in the opposite direction to the flow of electrons. This means that the electrons are repelled from the n-side and are unable to flow through the depletion layer to the p-side. This is why there is no flow of electrons from the p-type to the n-type and into the positive terminal of Vcc.

Additionally, the donor and acceptor ions in the n-side are already in a stable state and do not have any extra electrons to attract from the p-side. The excess of positive charges on the p-side also creates a barrier that prevents the flow of electrons to the n-side.

I hope this helps to answer your question. If you have any further queries, please don't hesitate to ask. it is important to always question and seek a deeper understanding of phenomena. Keep up the curiosity!