RAS question
Semiconductor chips are primarily made from:
Correct answer: (D) Silicon.
Semiconductor chips are primarily made from silicon, the dominant material used for integrated-circuit fabrication.
Explanation
Silicon is the right answer because semiconductor chips depend on a material whose electrical behaviour can sit between a conductor and an insulator. Silicon's abundance, moderate bandgap of about 1.1 eV, and ability to form silicon dioxide for insulation make it suitable for chip fabrication. Encyclopaedia Britannica supports the core device link: pure silicon is the most important material for integrated-circuit applications, and silicon has by far been the most widely used semiconductor for device fabrication. Silicon displaced germanium because silicon devices have lower leakage currents, and silicon dioxide is a high-quality insulator that can be incorporated into silicon-based devices. Germanium, gallium arsenide and silicon carbide are semiconductors too, but silicon is the primary chip material.
Why the other options are wrong
- (A) Copper is associated with wiring, whereas the chip's semiconductor body needs a material such as silicon rather than a wiring metal.
- (B) Gold may be used in wire bonding, but it is not the semiconductor material from which chips are primarily made.
- (C) Aluminium is used in interconnects and is listed by Britannica among high-conductivity conductors, so it is not the primary semiconductor chip material.
Concept
This tests the Science and Technology concept of semiconductor materials and their use in integrated circuits. It recurs in RAS because it checks whether aspirants can separate the semiconductor base material from metals used for wiring, bonding or interconnects.