How Does Current Flow in a P-N Junction at Equilibrium?

[atlbraves49]

I've been doing some practice semicon. problems and there are a few remaining ones I've been having issues solving. I'll do one at a time

Question: What happens when an n-type and p-type material are merged to form a p-n junction? Provide an explanation as to the amount of net current flow in a p-n junction under equilibrium.



I know that under reverse-bias, there is minimal current flow to cross the p-n junction but what about under equilibrium? Also I know generally what happens in a p-n junction but can't specifically put to words what is occurring on a more exact level... any suggestions ?

 

[Defennder]

What is the definition of "thermal equilibrium" in semiconductor physics? You need to explain what happens during the formation of a pn junction in terms of the hole/electron concentrations and the respective diffusion/drift currents.