The semiconductor manufacturing process starts with the production of silicon wafers.
Semiconductors are an ever-present element in modern technology. When judged by their ability to conduct electricity, these devices fall between complete conductors and insulators. They are used as part of a digital circuit in computers, radios, telephones and other equipment.
The semiconductor manufacturing process starts with the base material. Semiconductors can be made from a dozen such materials, including germanium, gallium arsenide, and various indium compounds such as indium antimonide and indium phosphide. The most popular base material is silicon because of its low production cost, simple processing and temperature range.
Once the semiconductor manufacturing process is complete, the finished semiconductors are extensively tested.
Using silicon as an example, the semiconductor manufacturing process starts with the production of silicon wafers. First, the silicon is cut into round wafers using a diamond-tipped saw. These wafers are then sorted by thickness and checked for damage. One side of the wafer is then etched in a chemical and polished as smooth as a mirror in order to remove all impurities and damage. Chips are built on the smooth side.
Cell phones, laptops and other devices rely on silicon semiconductors.
A layer of silicon dioxide glass is applied to the polished side of the silicon wafer. This layer does not conduct electricity, but it helps prepare the material for photolithography. The manufacturing process also applies layers of circuit patterns to the wafer after it is coated with a layer of photoresist, a light-sensitive chemical. Light is then projected through a reticle and lens mask so that the desired circuit pattern is printed on the wafer.
The photoresist pattern is removed by washing using a series of organic solvents mixed together in a process called incineration. The process results in a three-dimensional (3D) wafer. The wafer is then washed with wet and acidic chemicals to eliminate any contaminants and residue. Multiple layers can be added by repeating the entire photolithography process.
Once the layers have been added, areas of the silicon wafer are exposed to chemicals to make them less conductive. This is done by using doping atoms to displace silicon atoms in the original wafer structure. It is difficult to control how many doping atoms are deployed in an area.
The final task in the semiconductor manufacturing process is to coat the entire surface of the wafer with a thin layer of conductive metal. Copper is generally used. The metal layer is then polished to remove unwanted chemicals. Once the semiconductor manufacturing process is complete, the finished semiconductors are extensively tested.