Basic seiconductor question

[timkuc]

Basic semiconductor question

I don't know if I am asking some stupid questions but I can't really move without knowing them.

(1) In reverse bias situation electrons attracted towards positive terminal and hole attracted towards negative terminal widen the depletion region .My question is that why can't these hole combined and make a bond with the metal terminal because the negative terminal will give electrons to the p side [as battery always provides electrons].
(2) True or false ?
"The current in forward bias flows because the potential across the diode is more then the barrier potential but the current flows due the potential applied across it ,it is not the diffusion process in the diode which occurs after when the external voltage reduce barrier potential to zero."
I am very confused with very basics .

 

[Colbhaidh]

Think of the battery as providing potential energy (electric field) rather than kinetic energy (electrons flow).
When a depletion region is created due to the diffusion of electrons and holes across the PN junction, the depletion region becomes an insulator across which there is no motion of any carriers (holes or electrons). So the depletion regions is essentially an Open Circuit. Applying more reverse potential increases the width or size of this depletion region or open circuit. So no electrons or holes reach the battery terminals. If the reverse potential increases hgh enough, the insulator is catastrophically destroyed and carriers can breach this insulator. This is reverse breakdown.

In forward bias conditions, the depletion region width is reduced. If reduced far enough, the insulator disappears and current can flow under the influence of the external electric field.