To convert the Si crystal into p-type semi-conductor, which group element will be doped:

Explanation

Explanation:To convert a silicon (Si) crystals into a p-type semi-conductor, it needs to be doped with a trivalent element, which means an element that has three velence electrons in its outermost shell. This is because the Trivalent impurity atom will create a hole in the valence band, which behaves likes a positively charged particle. Second group elements have two valence electrons, so they cannot be used to create holes in the valence band. They are used to create n-type semiconductors by introducing an extra electron to the conduction band. Fourth group elements have four valence electrons, so they cannot be used to create holes in the valence band. This option is also incorrect. Pentavalent elements have five valence electrons, which means they can be used to create n-type semiconductors by providing an extra electron to the conduction band.