Physics 2005 JAMB Past Questions - Question 8: A silicon material is dopped with an element of a certain group and an n-type semi-conductor is formed. The most likely group of the element is

Correct Answer

C

Explanation

When silicon is doped with an element from a certain group to create an n-type semiconductor, the most likely group of elements used for doping is Group V (Group 15) of the periodic table. Group V elements, such as phosphorus (P), arsenic (As), and antimony (Sb), are often used as dopants to create n-type semiconductors in silicon.

These Group V elements have five valence electrons, one more than silicon, which has four valence electrons. When they are introduced into the silicon crystal lattice as dopants, they contribute an extra electron to the crystal structure, creating an excess of free electrons in the material. This excess of free electrons makes the silicon an n-type semiconductor, where electron charge carriers dominate the electrical conductivity.