1. Insulators do have some free electrons (charge carriers). If they had no
free electrons, their electrical resistivity would be infinite. Insulator
have some free electrons, typically less than 10^10/cm3. The electrical
resistivity of typical insulators decreases with increasing temperature,
indicating an increasing density of free electrons with increasing
temperature.
2. Electrons do not necessarily move more easily in a conductor than in a
semiconductor. A typical electron mobility in GaAs, an insulator is
10,000cm2/V-s, much higher than that of copper.
Larry Woolf; General Atomics; 3550 General Atomics Court, San Diego, CA
92121; Phone:858-455-4475; FAX:858-455-4268; http://www.sci-ed-ga.org
i have found in a book that insulators dont have any free electrons, where
in conductors, the electrons can move easily, therefore, semiconductors have
few free electrons so are in between insulators and conductors.
is this correct?