Question

The electrical conductivity ${\text{(in ohm}}^{-1}{\text{cm}}^{-1})$ of semiconductor is in the range of :

• A. ${10}^4\text{to}{10}^8$
• B. ${10}^{18}\text{to}{10}^{22}$
• C. ${10}^{-6}\text{to}{10}^4$
• D. none of the above

Answer 1

Answer: (C)

${10}^{-6}\text{to}{10}^4$

In insulators, the electrons in the valence band are separated by a large gap from the conduction band while in conductors like metals, the valence band overlaps the conduction band and in semiconductors, there is a small enough gap between the valence and conduction bands such that thermal or other excitations can bridge the gap.
Semiconductors have conductivity in the range of ${10}^{-6}\text{to}{10}^4{\text{ohm}}^{-1}{\text{cm}}^{-1}$.