Question

Which type of semiconductor is formed when germanium is doped in the gallium as indicated in the figure?

• A. $p$-type semiconductor $\quad Ge\, Ge \,Ge\, Ge$
• B. $n$-type semiconductor $\quad Ge \,Ge\, (Ga) \,Ge$
• C. No change in conductivity $\quad Ge\, Ge \,Ge \,Ge$
• D. It becomes superconductor $\quad Ge\, Ge\, Ge \,Ge$

Answer 1

Answer: (A)

In the given figure, the base element is $Ge$ and it is doped with $Ga$. Here the impurity is a trivalent element.
It creates deficiencies of valence electrons, called "holes". This makes the material a p-type semiconductor.