RESISTIVITY OF VARIOUS MATERIALS
For ideal conductor, resistivity is zero and for ideal insulator , the resistivity is infinite.
Metals have low resistivities in the range of $10^{-8} \Omega m$ to $10^{-6} \Omega m$. At the other end are insulators like ceramic, rubber and plastics having resistivities $10^{18}$ times greater than metals or more. In between the two are the semiconductors. These, however, have resistivities characteristically decreasing with a rise in temperature. The resistivities of semiconductors can be decreased by adding small amount of suitable impurities.
Resistivity of material is inversely proportional to its conductivity therefore conductivity of conductor is more than that of semiconductor. the conductivity of a semiconductor is more that of an insulator