# Depletion Layers in pn junction

Hi,

Can someone please tell me if it is true that in heavily doped pn junctions, the electric field that prevents further diffusion of holes and electrons is set up more quickly than in less heavily doped pn junctions? Is this essentially because the holes and electrons recombine more quickly and very near the join between the p and n type semiconductors, which occurs because the charges don't need to travel very far before they recombine?
So then is this the reason why depletion layers for such pn junctions are narrower than for less heavily doped pn junctions?

Thanks a lot.