Today is World Book Day 

Open a book about chemistry 

You will see a special type of gas 

It is an inert gas 

About inert gases 

Which of the following gases do you know is an inert gas?

A, Helium B Fluorine C Hydrogen 

Answer: A Helium 

Inert gases (also known as noble gases) are a group of elements on the far right of the periodic table, including helium ( He ), neon ( Ne ), argon ( Ar ) etc. Their chemical properties are extremely inactive, and they are not easy to react with other substances. In MFC leak detection, the most commonly used gas is helium, an inert gas. 

Why are inert gases "lazy"? 

Inert gases have a "perfect" outermost electron arrangement, that is, the number of electrons just fills the orbital, forming a stable structure (such as helium's 2 and neon's 8 ). This " full ” " state makes them unwilling to grab other people's electrons, nor willing to share their own, so they hardly participate in chemical reactions, becoming the " high-cold homebodies ”。

Application of inert gases in chip manufacturing 

In the semiconductor manufacturing process, when using inert gases (such as argon and helium), there are many requirements for mass flow controllers ( MFC ), mainly in the following aspects: 

Material compatibility 

Inert gases themselves are chemically stable, but semiconductor processes require extremely high gas purity (such as 99.9999% or more). MFC Materials (such as seals and channel walls) must avoid releasing contaminants (such as particles, organic matter, or metal ions). 

Recommended materials : Stainless steel (such as 316L ), electropolishing ( EP ) or chemical polishing ( CP ) treated inner surface, the sealing material commonly uses perfluoroether rubber ( FFKM ) or high-purity polytetrafluoroethylene ( PTFE ). 

Accuracy and stability 

High precision requirements : Semiconductor processes usually require MFC an accuracy of ±1% F.S. (full scale) or higher, and some key steps (such as atomic layer deposition ALD ) require ±0.5% F.S. 。

Low flow control : Some processes require extremely low flow rates (such as SCCM level), MFC requires low range capability and fast response characteristics. 

Leak rate and sealing 

Ultra-high sealing requirements : Although inert gases are non-toxic, leakage may affect the pressure in the process chamber or lead to gas waste. MFC The leak rate must meet SEMI standards (such as ≤1×10 ⁻⁹ atm · cc/sec He ). 

Pressure resistance and flow range 

Process adaptability : According to the process pressure (such as low-pressure CVD or high-pressure injection), select MFC the pressure resistance range. 

Wide range ratio Supports precise control from low to high flow rates. 

Summary :

Inert Gases for Semiconductor Applications MFC Must meet High precision, low leakage, material compatibility and other core requirements. 

Product Recommendations: 

AURASKY has multiple series of gas mass flow controllers, such as Pressure-type gas mass flow controller DS312、 Thermal digital gas mass flow controller CS316 etc., with product features including High precision 、 Fast response 、 High reliability 、 Corrosion resistance and Multi-gas compatibility etc., and is able to Meet the needs of different processes in semiconductor manufacturing 。