Perfluoroelastomers (FFKMs) Dupont Kalrez® are used as seals on wafer processing equipment due to their extraordinary resistance to chemicals, including reactive plasmas and extreme heat as high as 620°F (327°C). FFKM performance can vary depending upon the chemical composition. Specially formulated Kalrez products may be required to help reduce wafer contamination.
Fabricators have found that plasma is a very powerful tool for etching, CVD and stripping because all materials are consumed. FFKM seals are used in these processes because of their exceptional resistance to aggressive media. Prolonged exposure to plasmas can degrade seal surfaces resulting in particulate contamination even before sealing functionality is lost. The ideal seal, therefore, would resist surface degradation while maintaining sealing functionality. Kalrez seals are designed to with stand chemical attack and provide extended seal life. They exhibit low weight loss and particle generation, thus improving wafer yield,increasing process reliability and reducing frequency of equipment maintenance. See the relative particle generation in plasma for four FFKM compounds.
Recognized as the leading supplier of perfluoroelastomer parts for over 40 years, DuPont offers a variety of high performing products that are formulated to give the best possible seal performance in numerous aggressive environments. Excellent balance of finished properties is achieved through careful use of proprietary polymers, cure systems, fillers and additives, resulting in superior seals for a broad range of applications.
Kalrez® 4079 is among the most popular of all Kalrez compounds. Released in the 1980's, this compound has been a mainstay and go-to for many Gallagher customers.
Kalrez® 4079 parts are a low compression set product for general purpose use in O-rings, diaphragms, seals and other parts used in the chemical process and aircraft industries.
DuPont has developed a unique seal design to improve seal life in dovetail grooves. This design benefits from the excellent chemical, thermal and plasma resistance of DuPont™ Kalrez® perfluoroelastomer parts with a unique cross-sectional trilobe seal that eliminates many of the problems associated with semi-dynamic seal applications using a dovetail groove. These problems include installation difficulties as well as short seal life and particle generation due to seal wear and degradation.
For over 40 years, DuPont™ has been relentless in pursuing improvement in the manufacture of perfluoroelastomer (FFKM) parts. Elastomeric parts typically consist of three components: a polymer chain (the backbone of the elastomer), a crosslinking system (which links the polymer chains together and is the key to elasticity and sealing performance), and a filler system (used to enhance mechanical properties). Based on extensive experience, DuPont™ adjusts these components to optimize seal performance.
For demanding standard and complex composite seal applications, Kalrez perfluoroelastomer parts are the elastomer of choice designed and molded to your specific requirements. Kalrez composite seals offer unique one of a kind parts, in a wide variety of custom family shapes, standard geometry, and miscellaneous bonded parts, including small and large parts. Whether you have a niche application or high volume runs, your sealing requirements can be met. Kalrez composite seals are available in a variety of compounds depending on the thermal, chemical and plasma resistance required.
Kalrez® composite seal applications include; micro valves, micro-pumps, downhole oil and gas, semiconductor chip process equipment, ink jet, beverage dispensers, car wash pumps, printers, paint spray, refineries, CPI and more.
Amine treatment is a process typically used for Hydrogen Sulfide removal from natural gas (sour gas). This operation is commonly referred to as gas “sweetening," acid gas removal, or amine scrubbing
Amine units are used all over the world in oil refineries and gas plants to remove hydrogen sulfide (H2S) from a product stream. New environmental standards are more strict and require ever-decreasing contents of H2S in clean natural gas. Most of the new sources of oil and gas discovered today have high contents of H2S which demand more efficient removal technologies (the Shah Gas
Kalrez Spectrum 7275 is a perfluoroelastomer that provides long life sealing in an array of aggressive chemical environments that typically make sealing difficult: ethylene oxide, acrylic monomers, silanes and chlorosilanes, and strong oxidizers such as nitric acid, chlorine and chlorine dioxide.
It has demonstrated improved chemical and compression set resistance and mechanical property retention when compared to competitor’s elastomers.
Kalrez Spectrum 7275 is based on a proprietary cross-linking system, and is uniquely identified by its light brown shade.
Targeted applications include industries that depend on mechanical seals, pumps, valves, compressors, filtration columns and analytical equipment for their critical processes.
To meet growing demand in solar cells, the Siemens* process is used to produce highly purified polycrystalline silicon by thermally decomposing tri-chloro-silane (TCS). The reactors employed require three kinds of high-performance seals in the following locations: A) bell jar seals; B) electrode seals between the electrode and ceramic inlet; and C) a gasket for the view port seal (see schematic).
The process involves a very hot, dry environment with temperatures up to 1200°C (2100°F). Sealing components see up to 300°C (572°F). Process media include TCS and aggressive by-products of its decomposition, such as HCl gas. Superior compression set performance is needed for effective sealing and extended seal life. Very low outgassing is a key requirement for preventing contamination of the process environment.
The presence of harsh chemicals in high temperature conditions often require an upgrade from standard sealing materials to PTFE or fluoroelastomers (FKM) to improve thermal stability and chemical resistance. However, PTFE can deform and creep “hot flow” in the bell jar seal increasing the risk of product loss. FKM, with its high temperature rating of 200°C (392°F), also has deficiencies in this 300°C (572°F) environment.
Kalrez PV8070 perfluoroelastomer parts installed as washers and gaskets in reactors for the Siemens CVD process have demonstrated outstanding performance in this demanding application. Kalrez® PV8070 parts are effective seals that provide:
Bonded door seals for gate valves and slit valve door seal applications provide improved sealing performance versus conventional O-rings by reducing particle generation, extending seal life, and minimizing replacement time during preventive maintenance.
DuPont™ Kalrez® bonded door seals are designed for easy installation and low particle generation. They combine a custom seal design and proprietary adhesion technology along with the excellent plasma resistance of Kalrez® perfluoroelastomer seal materials developed for semiconductor applications. The seal is held
DuPont™ Kalrez® 1050LF perfluoroelastomer parts are a carbon black-filled general-purpose product for o-rings, seals, and other parts used in chemical process industries. It is a classic-grade and longtime favorite for premium performance and provides a more economical option than similar compounds such as 7375.
Kalrez 1050LF o-rings can maintain their recovery with elasticity following high-pressure applications, maintaining a tighter seal for longer periods of time compared to other compounds. With a pressure rating of 1,500 PSI, it can help extend seal life and integrity, ultimately lowering costs.
With above-average hot water
Oil and gas production and chemical manufacturing industries present sealing technologies with some of the harshest and most demanding operating environments.
"We screen Kalrez against some of the most aggressive corrosive fluids," says Dr Christopher Bish, Technical Fellow. "And in addition to the fluid testing, we did some compression set testing and stress relaxation testing at high temperatures. We now have one of the most chemically resistant and thermally stable compounds possible."
We screen Kalrez against some of the most aggressive corrosive fluids
One of the things that sets Dupont Kalrez apart is their quality control system, which gives them the ability to track materials as they flow through the plant. Scanning the barcode on