Question #7b6ca

1 Answer
Sep 5, 2017

No semiconductor devices are not electrically charged.

You take a p type semiconductor. You have an excess of holes in the crystal which are positively charged mobile charge carriers. However, there are any equal number of electrons (most of them immobile) in the solid so that charge neutrality is always maintained.

For an npn transistor, the two n regions of emitter and collector constitute a large number of mobile electrons (and equal number of positive charges to maintain charge neutrality) and hence, majority carriers in the transistor are electrons.

In the case of a pnp transistor, majority of the carriers are holes.

But no transistor is electrically charged.