How A Microchip Is Made

 Microchips are built from wafers that

consist of 99.9% pure silicon.

The silicon is made from common beach sand.

The chips are made in incredibly clean environments -

the air is more than 1000 times purer than that of a hospital.

The silicon wafers are produced by a specialist company

and sent to the chip manufacturer

for processing.

The Silicon wafer consists of 4 layers.

A mask that is created during the design phase defines the cicuit pattern.

A mask is placed over the wafer, under a UV light. Patterns are repeatedly projected on the

wafer, light can only reach the wafer through the openings.

The UV light reacts with the photoresist to create the circuit patterns.

Impurities are then implanted into areas of the wafer to alter the electrical properties of

specific regions. This is called doping.

Electrical contacts are formed by masking and etching the wafer to provide links between

the different layers.

Multiple layers of metal are applied to form the electrical connections between the chips's

layers.

The final chip is housed in a protective case that contains wires to connect it to the

computer's circuit boards.