How may the conductivity of an intrinsic semiconductor be increased?

Intrinsic semiconductors are undoped or pure semiconductor without having any impurities. They are formed using group 14 elements like Silicon only.

To increase the conductivity of these semiconductors we do doping. Doping is mixing impurities of elements of Group 13 and 15 with the intrinsic semiconductors. In this way, the doped semiconductor formed has higher conductivity. These semiconductors are known as extrinsic semiconductors. They are of n-type and p-type. Also, conductivity of intrinsic conductors can be increased by increasing the temperature as the increase in temperature pushes a greater number of electrons from valence band to conduction band which helps in conduction.

n-type and p-type semiconductors

Band gap in semiconductors.