Question

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

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

Answer 1

The correct option is B p-type semi conductor

p-type of semiconductors are produced due to metal deficiency defects
n- type semiconductor by adding impurity
containing less 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.