At the outset, I may be allowed to clarify the following point regarding extrinsic/intrinsic and impure/pure semiconductor.
An extrinsic semiconductor is necessarily impure (has chemical impurities or lattice defects), but, an impure semiconductor is not necessarily extrinsic. For example, if you add 10 B and 10 P atoms to intrinsic Si, and these are all ionised, the Si will still remain intrinsic. (Also, we may remember that in a given semiconductor, only a small fraction of the elements qualify as dopants and are capable of making the semiconductor extrinsic.)
The definition of intrinsic semiconductor is that n=p in that material. The definition of extrinsic semiconductor is that n>p or n
matter has to stay neutral
if not let's say it gets electron charged it will attract, thanks to coulomb interecation, positive charges until neutrality gets respected
"Extrinsic" only means it is not pure. The impurities added are in the form of a neutral atom. If an impurity replaced a host atom, the host atom is taken out as a whole. "Matter has to stay neutral" in equilibrium.
At the outset, I may be allowed to clarify the following point regarding extrinsic/intrinsic and impure/pure semiconductor.
An extrinsic semiconductor is necessarily impure (has chemical impurities or lattice defects), but, an impure semiconductor is not necessarily extrinsic. For example, if you add 10 B and 10 P atoms to intrinsic Si, and these are all ionised, the Si will still remain intrinsic. (Also, we may remember that in a given semiconductor, only a small fraction of the elements qualify as dopants and are capable of making the semiconductor extrinsic.)
The definition of intrinsic semiconductor is that n=p in that material. The definition of extrinsic semiconductor is that n>p or n
All extrinsic semiconductors have internal charges that include ionized dopants, electrons, and holes. But at equilibrium they have no net charge and thus are charge neutral.
They aren't electrically charged at the equilibrium state but outside this case it exists some carriers that can move in the semiconductor, mainly due to the thermal activity
the impurity were not initially charged so it is obvious that the material remains neutral
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