P-N junction charge utilisation

by messysmurf
Tags: charge, junction, utilisation
messysmurf is offline
Apr16-12, 08:49 AM
P: 6

A depletion region forms instantaneously across a P-N junction. When N-doped and P-doped pieces of semiconductor are placed together to form a junction, electrons migrate into the P-side and holes migrate into the N-side. As such, in the depletion region, the P-side becomes negatively charged with respect to the N-side which is positively charged,

If an external conductor is made to connect the P and N areas of the depletion region, then a current must flow as there is a potential difference between the N and P areas of the depletion region. The effect of such conductance is to cause the charge difference, in the depletion region, between the N and P doped materials to diminish.

My question is, will the P-N junction spontaneously tend to replenish the charge difference between the P and N doped pieces and hence cause current to continuously flow in the external conductor? Alternatively, if the conductor is periodically attached and detached, will this allow the spontaneous formation of charge separation to be utilised to generate current?

Regards, Tim.
Phys.Org News Partner Physics news on Phys.org
Physicists design quantum switches which can be activated by single photons
'Dressed' laser aimed at clouds may be key to inducing rain, lightning
Higher-order nonlinear optical processes observed using the SACLA X-ray free-electron laser

Register to reply

Related Discussions
The correct movement of charge in PN junction Advanced Physics Homework 0
pn junction Introductory Physics Homework 0
transistors-Why can't a pn junction and np junction in series be a pnp transistor? Atomic, Solid State, Comp. Physics 3
Difference between charge, specific charge, relative charge and elimentary charge? High Energy, Nuclear, Particle Physics 1
PN junction Advanced Physics Homework 0