Producing polycrystalline silicon involves dissolving metallic silicon in hydrochloric acid (HCI) and refining trichlorosilane (SiHCI₃)to increase the purity.
The SiHCI₃ is then allowed to react with ultra-pure hydrogen (H₂) in a reaction vessel (bell jar) to precipitate and grow cylindrical polycrystalline silicon.

Monocrystalline Si ingot manufacturing processes are broadly divided into the Czochralski (CZ) process and the Floating Zone (FZ) process.
Both processes involve manufacturing monocrystalline silicon ingots by growing monocrystals in argon gas.

Silicon oxide film formation processes include the thermal oxidation process, dry O₂ oxidation process, wet O₂ oxidation process, the pyrogenic oxidation process (which involves combusting H₂ gas and O₂ gas externally and supplying this as water vapor),
and the hydrochloric acid oxidation process (which involves adding hydrogen chloride (HCl) gas to N₂ and O₂ gas).

A silicon nitride film is deposited on top of the silicon oxide film by chemically reacting silane (SiH₄) and ammonia (NH₃) gas at high temperature.

Lithography involves coating the surface of a silicon wafer with photoresist and exposure via a photomask using an exposure machine to transfer the circuit pattern from the photomask.
The residual areas of resist are removed from the exposed wafer using a remover.

The CVD (Chemical Vapor Deposition) technique involves depositing a new film on a wafer by allowing the raw material gas (film generating gas) to chemically react in a reaction chamber.

The PVD (Physical Vapor Deposition) technique forms a film by promoting the collision of argon (Ar) ions generated in a plasma against a target inside a vacuum chamber and depositing the ejected target atoms on a wafer.

The epitaxial technique forms new crystals on a monocrystal substrate.
A wide range of gases are used, depending on the substrate being manufactured.

This is a technique for intentionally adding trace amounts of impurities to a wafer to ensure efficient semiconductor function.
This is also called doping, and the gas used in doping is called the doping gas.

This technique is used to inject impurities into a wafer by ionizing atoms of the impurity and subjecting them to acceleration sufficient to drive them into silicon crystals.

Etching is a technique for forming circuits on semiconductors using the corrosive action of chemicals or gases.
There are two types of etching processes: dry and wet.

CMP (Chemical Mechanical Polishing) is a polishing technique for smoothing the finish of a wafer surface.
Washing is necessary following CMP, and various solutions and methods are used depending on the washing requirements.