Pure silicon can be converted to a p-type by adding a controlled amount of
Answer Details
Pure silicon can be converted into a p-type semiconductor by adding a controlled amount of trivalent atoms.
A semiconductor can be classified into two types: p-type and n-type. A p-type semiconductor is created by adding impurities to pure silicon such that some of the silicon atoms are replaced by impurity atoms that have one less valence electron than silicon. These impurities are called acceptors since they accept electrons in the crystal structure.
The trivalent impurities, such as boron, aluminum, and indium, have three valence electrons, and when they are added to the pure silicon crystal, they create "holes" or vacant spaces where an electron is missing. These holes act as positive charge carriers in the semiconductor, and they are attracted to the negatively charged regions of the crystal.
By adding a controlled amount of trivalent impurities, the p-type semiconductor can be created with a certain level of conductivity. The impurities are added in such a way that the concentration of holes is much greater than the concentration of electrons, which results in the p-type semiconductor being a majority carrier hole semiconductor.
In contrast, the n-type semiconductor is created by adding pentavalent impurities, such as phosphorus, arsenic, or antimony, to the pure silicon crystal, which have one more valence electron than silicon. These impurities are called donors since they donate extra electrons to the crystal structure, which then act as negative charge carriers.
Therefore, the answer to the given question is option (A) trivalent atoms.