JAMB Physics 2022 Paper

Concept:A semiconductor is a solid material whose atoms are held together by a specific type of chemical bond.Explanation:Pure semiconductors such as silicon ($\mathrm{Si}$) and germanium ($\mathrm{Ge}$) form a crystal lattice.In this lattice, each atom shares its four valence electrons with four neighbouring atoms.This sharing of electron pairs creates covalent bonds between the atoms.The presence of covalent bonds gives the material its semiconducting properties.Impurities may be added to change conductivity, but the basic structure is still held together by covalent bonds.Thus, a semiconductor is formed by covalent bonding.Answer:D. covalent bonds