Classification by Application:

Electronic gases: Used in the electronics and semiconductor industry, such as silane (SiH₄), dichlorosilane (SiH₂Cl₂), 

phosphine (PH₃), arsine (AsH₃), and nitrogen trifluoride (NF₃). They are widely used in processes such as epitaxy, 

ion implantation, etching, and chemical vapor deposition.

Standard gases: Mainly used for calibration and testing, such as single- or multi-component standard gases prepared 

with nitrogen (N₂), oxygen (O₂), and argon (Ar). They are commonly used in the petroleum, chemical, environmental 

protection, and sensor calibration industries.

Environmental gases: Used in environmental monitoring and remediation, such as sulfur dioxide (SO₂) and nitrogen 

oxides (NOₓ). Standard gases can be used to monitor air pollution, and some gases can also be used for waste gas treatment.

Medical gases: Used in the medical field, such as oxygen (O₂) and nitrous oxide (N₂O). They can be used for anesthesia and 

respiratory support. Welding gases: These gases, such as argon (Ar) and carbon dioxide (CO₂), are used during the welding 

process. They act as shielding gases to prevent oxidation at the weld site.

Sterilizing gases, such as ethylene oxide, are used to sterilize medical devices and food packaging.

Classification by chemical composition:

Silicon-based gases: such as silane (SiH₄), silicon tetrachloride (SiCl₄), and silicon tetrafluoride (SiF₄).

Arsenic-based gases: such as arsine (AsH₃) and arsenic trichloride (AsCl₃).

Phosphorus-based gases: such as phosphine (PH₃) and phosphorus trichloride (PCl₃).

Boron-based gases: such as boron trichloride (BCl₃) and boron trifluoride (BF₃).

Metal hydrides: such as borane (B₂H₆).

Halides: such as chlorine (Cl₂), hydrogen bromide (HBr), and hexafluoroethane (C₂F₆).

Metal hydrocarbons: such as trimethylgallium (Ga(CH₃)₃).

Classification by function in integrated circuits:

Dopant gases, such as borane, phosphine, and arsine, are used to introduce impurity atoms into semiconductors, 

altering their electrical properties.

Epitaxial gases, such as silane and silicon tetrachloride, are used to grow an epitaxial layer with the same or similar

 crystal structure on a semiconductor substrate.

Ion implantation gases, such as phosphine, arsine, and borane, are used to inject ionized impurity gases into 

semiconductor wafers for purposes such as doping.

LED gases, such as nitride gases, are used in the LED manufacturing process.

Etching gases, such as chlorine, nitrogen trifluoride, and carbon tetrafluoride, are used to remove unwanted material 

from the wafer surface and form specific patterns.

Chemical vapor deposition (CVD) gases, such as silane, ammonia, and carbon dioxide, are used to deposit thin films on

 wafer surfaces through chemical reactions.

Carrier dilution gases, such as nitrogen and argon, are used to carry other reactive gases or to dilute reactive gases.