Net current in a semiconductor

[sahil_time]

We know that the built in potential barrier Vb does not allow any net current in a semiconductor. Now when we connect a battery in forward biased with the voltage V the current begins to flow even if V<Vb. Agreed. But my text says that V cannot exceed Vb is this true? for reference
http://books.google.co.in/books?id=...&resnum=6&ved=0CD0Q6AEwBQ#v=onepage&q&f=false

 

[Drakkith]

I don't know much about this subject, but if that's what your textbook says then I'd say it is probably true.

 

[sahil_time]

The text didn't provide a reason. But i was thinking that if V>Vb there will be no barrier hence the current will be too large and that might damage the device. Can this be the reason?

 

[Drakkith]

The text dint provide a reason. But i was thinking that if V>Vb there will be no barrier hence the current will be too large and that might damage the device. Can this be the reason?

No idea. Anyone else know?

 

[granpa]

sounds like its talking about diodes and pn junctions.

you do understand that there is forward and reverse bias?

 

[sahil_time]

yeah.yeah. so what do you propose?

 

[berkeman]

We know that the built in potential barrier Vb does not allow any net current in a semiconductor. Now when we connect a battery in forward biased with the voltage V the current begins to flow even if V<Vb. Agreed. But my text says that V cannot exceed Vb is this true? for reference
http://books.google.co.in/books?id=...&resnum=6&ved=0CD0Q6AEwBQ#v=onepage&q&f=false

yeah.yeah. so what do you propose?

Are you familiar with the Diode Equation? What is the relationship between current and voltage for a pn junction diode?

If you're not familiar with the equation yet, check wikipedia.com