Which of the following is an intrinsic semiconductor whose electrical conductivity can be significantly altered by the intentional addition of impurity atoms in a process called doping?

💡 Solution & Explanation

Pure crystalline silicon is an intrinsic semiconductor whose electrical conductivity is extremely low at room temperature but can be precisely engineered through the introduction of impurity atoms in a process called doping. Copper wire is a metallic conductor with high free electron density, whereas sodium chloride in molten form conducts electricity via mobile ions rather than semiconducting band gaps. Doping silicon with group 13 or 15 elements creates p-type and n-type semiconductors foundational to modern electronics.