Question

On doping $Ge$ metal with a little $In$ or $Ga$, one gets:

• A. n-type semi conductors
• B. insulator
• C. rectifier
• D. p-type semi conductor

Answer 1

The correct option is D p-type semi conductor

p-type of semiconductors are produced due to metal deficiency defects.
n-type semiconductor produced by adding impurity
containing less number of electrons (i.e., atoms of group 13).
$Ge$ belongs to group $14$ and $In$ or $Ga$ to group $13$.
Hence on doping, p-type semiconductor is obtained. This
doping of $Ge$, with $In$ increase the electrical conductivity of the $Ge$ crystal.