Q102
General SciencePhysics
Which of the following elements is a semiconductor?
- a.Iron
- b.Zinc
- c.Mercury
- d.Silicon
Answer: (D) Silicon
Silicon is a semiconductor: its conductivity lies between that of conductors and insulators and rises with temperature or when small amounts of impurities are added (doping). Germanium is the other elemental semiconductor; both belong to Group 14 and are metalloids, while gallium arsenide is a compound semiconductor. Doping with phosphorus or arsenic gives n-type and with boron or aluminium gives p-type material, the basis of diodes, transistors, integrated circuits and solar cells. Iron and zinc are ordinary metallic conductors, and mercury, the only metal that is liquid at room temperature, also conducts electricity.