199- When we add a three-valent impurity like aluminum (similar to silicon) to a semiconductor, in terms of capacity:
In addition to the empty bands related to electrons that have gone to the conduction band, one electron is also added for each aluminum atom.
In addition to the empty bands related to electrons that have gone to the conduction band, one hole is also created for each aluminum atom.
The number of holes will be less than the number of electrons.
Equal numbers of electrons and free holes will be created.
\textbf{199-} When we add a three-valent impurity like aluminum (similar to silicon) to a semiconductor, in terms of capacity:
\begin{enumerate}
\item In addition to the empty bands related to electrons that have gone to the conduction band, one electron is also added for each aluminum atom.
\item In addition to the empty bands related to electrons that have gone to the conduction band, one hole is also created for each aluminum atom.
\item The number of holes will be less than the number of electrons.
\item Equal numbers of electrons and free holes will be created.
\end{enumerate}