FFKM is a high-performance sealing material. Its excellent performance has allowed its application to penetrate into the entire manufacturing system of semiconductor products. Among them, FFKM sealing rings are one of the main consumables required for the production of integrated circuits.
the structure and performance characteristics of FFKM
FFKM is copolymerized by tetrafluoroethylene (TFE), perfluoroalkyl vinyl ether (PAVE) as the main monomers, and a small amount of cure point monomer (CSM). As shown in the figure below, all carbon atoms in the polymer The hydrogen atoms on the rubber are all replaced by fluorine atoms, making it a rubber that does not contain C-H bonds at all.
Main performance features of FFKM:
1) Physical properties
The density of FFKM is 1.9-2.0g/cm³. Its normal temperature mechanical properties are close to those of vinylidene fluoride (VDF)-based fluororubber (FKM), but its high-temperature mechanical properties are better than those of fluororubber.
2) Chemical resistance
There are no hydrogen atoms in the FFKM molecular chain, and the C-C bonds are basically surrounded by a shell composed of F atoms, showing strong chemical inertness and making the polymer significantly resistant to chemicals.
3) High and low temperature resistance
The operating temperature of FFKM is generally 260~290℃, and can be used intermittently at high temperatures of 316℃. Since a large number of -OCF3 groups are introduced into the branch chains of the molecules, the flexibility of the molecules is improved and the low-temperature resistance of the rubber is improved.
4) Plasma resistance
In a plasma environment, it exhibits product characteristics of high cleanliness and low precipitation, and can withstand plasma bombardment for a long time.
fFKM'S applications in semiconductors
In semiconductor manufacturing, the reliability of elastomeric seals is critical because production shutdowns to replace seals are extremely costly. In order to avoid potential risks, the requirements for the cleanliness and purity of seals are very strict. At the same time, the seals must be able to work for a long time in the pressure environment of high temperature, high vacuum and corrosive chemical gases.
In terms of semiconductor applications, FFKM mainly focuses on:
1) Gas seal: In the semiconductor manufacturing process, the processing and transportation of various gases are essential. FFKM O ring are used for sealing gas pipelines, valves and joints to ensure that gas does not leak and maintain process stability.
2) Etching and cleaning: Etching and cleaning steps in semiconductor processes often involve the use of corrosive media such as strong acids or alkalis. FFKM O ring are widely used in equipment parts in contact with these media, such as etching chambers, cleaning tanks, etc. due to their excellent corrosion resistance.
3) Liquid and chemical transportation:In semiconductor manufacturing, various liquids and chemicals need to be transported, such as solutions, solvents, cleaning fluids, etc. FFKM O ring can be used to seal equipment components such as pipes, valves and pumps to ensure the safe delivery of media.
4) High temperature environment:Certain steps in the semiconductor process need to be performed in a high-temperature environment, such as heat treatment, annealing, etc. FFKM O-rings have excellent high temperature resistance and are able to maintain their elasticity and sealing properties at high temperatures.
5) Ultrapure water treatment:In semiconductor manufacturing, ultrapure water is used to clean and purify equipment and materials. FFKM O-rings are widely used to seal ultrapure water treatment equipment to prevent the entry of impurities and contaminants.
Due to the high cost of FFKM rubber raw materials, the working conditions where FFKM seals are usually used are extremely harsh. Under these harsh working conditions, other rubbers are prone to corrosion, swelling, dissolution, aging and hardening, etc., resulting in sealing failure and therefore cannot meet the sealing requirements. Due to its excellent corrosion resistance and high temperature resistance, FFKM rubber can not only meet the sealing requirements of harsh working conditions, but also increase the service life of seals and reduce customers' maintenance costs.
