How does the change in temperature and application of electric field affect the behavior of materials and write the range of resistivity for each materials.

Explanation

(i) The gape is very large that electrons from valence band cannot move into conduction band even on the application of strong external electric field or the increase in temperature.
(ii) The electrical conduction is not possible as the free electrons are almost nil.
(iii) Its resistivity is in the range of `10^(11)-10^(19)Omegam`.
Metals
(i) Condition become possible even at low temperatures.
(ii) The application of electrical field provides sufficient energy to the electrons. to drift in a particular direction to constitute a current.
(iii) The resistivity value lies between `10^(-2) and 10^(-8) Omegam`
Semiconductors
(i) At a finite temperature, thermal agitations in the solid can break the content bond between the atoms.
(ii) This release some electrons from valence band to conduction band.
(iii) The resistivity value of semiconductor is from `10^(-5) " to " 10^(6)Omegam`
(iv) When the temperature is increased further, more number of electrons is promoted to the construction band and increase the construction.
(v) Thus, electronic conduction increase with the increase in temperature