Pure silicon at $300 \ K$ has equal electron and hole concentration of $1.5 \times 10^{16} \ m^{-3}$. If the hole concentration increases to $3 \times 10^{22} \ m^{-3}$,then the electron concentration in the silicon is

The semiconductors are generally

$A$ silicon specimen is made into a $P$-type semiconductor by doping,on an average,one Indium atom per $5 \times 10^7$ silicon atoms. If the number density of atoms in the silicon specimen is $5 \times 10^{28} \text{ atoms}/m^3$,then the number of acceptor atoms in silicon per cubic centimetre will be:

In an $n$-type silicon,which of the following statements is true?

When an $n$-type semiconductor is heated,

$A$ $P$-type semiconductor is .......