Semiconductor
High vacuum, reactive plasma, aggressive process chemistry and tight thermal cycles across deposition, etch and lithography tools. O-rings and backup rings selected to hold up in every step.
Semiconductor · evolast® FFKM O-rings
Every chamber lid, gas line, slit valve and showerhead in a semiconductor tool is sealed by an O-ring. It is the one elastomer part that sees the plasma, the process chemistry and the thermal cycle directly. evolast® is MCM’s perfluoroelastomer family, made in a clean room and graded for each process step, so the seal is chosen for what the step throws at it.
Where the O-ring sits
A fab runs wafers through wet benches, furnaces and plasma chambers, and the O-ring in each tool faces a different enemy. MCM grades evolast® by process step rather than by a single catch-all compound, so hardness, colour and temperature window match the job.
WET CHEMICAL
Cleaning, wet etch and strip
Acid and solvent baths, hot DI water and ozonated rinses attack ordinary elastomers at the seal face. PS152 is the wet-process grade: 75 Shore A, black, built for immersion in aggressive chemistry.
PS152 · -25 °C to +275 °C
THERMAL
Furnace, diffusion and CVD
Repeated bakes and deposition cycles cook the seal and cause ordinary O-rings to harden and take a set. PS221 and PS251 are the thermal grades, with PS251 rated to 340 °C for the hottest hardware.
PS221 · PS251 · up to +340 °C
PLASMA
Dry etch, PECVD and ash
Fluorine and oxygen plasma erode the exposed seal and shed particles onto the wafer. The PS32x and PS34x plasma grades are formulated for low erosion, low particle generation and low outgassing under direct plasma exposure.
PS321 · PS341 · PS342 · PS343 · up to +330 °C
Why evolast®
-46 °C to +350 °C
The family spans cryogenic lines to the hottest thermal hardware, with individual grades rated for their own windows.
Near-universal chemical resistance
Acids, solvents, ketones, esters, amines, hot water and steam. evolast® FFKM carries more fluorine than FKM, which is what buys that resistance.
Low particles, low outgassing
Plasma grades are formulated to shed less and release less, which is what keeps the seal from becoming a defect source on the wafer.
Made and packed in a clean room
MCM molds, washes and post-cures semiconductor seals under ISO 7 and sanitises and packs them under ISO 6.
Manufacturing
Moss Seal’s partner MCM makes its semiconductor seals in a dedicated clean room. Super-filtered air is recirculated through a sealed room while temperature, humidity and pressure are held steady, keeping dust, airborne particles and chemical vapours away from the parts.
ISO 7 · Manufacturing
Extrusion
Production starts inside the clean room.
Molding
Compression and injection molding machines.
Washing
Parts go through a dedicated washing system.
Post-curing
Post-curing also happens in the clean room.
ISO 6 · Packaging
Sanitising & packing
Finished seals are sanitised and packaged under ISO 6 conditions.
A strict quality control system runs alongside every stage.
evolast® grades by process
Hardness in Shore A. Temperature windows as published by MCM.
PS152
75 · Black
-25 to +275 °C
Wet chemical
PS221
75 · Amber
-15 to +275 °C
Thermal
PS251
75 · Black
-15 to +340 °C
Thermal
PS321
65 · Black
-15 to +275 °C
Plasma
PS341
75 · Brown
-15 to +330 °C
Plasma
PS342
65 · Brown
-15 to +325 °C
Plasma
PS343
75 · Brown
-15 to +325 °C
Plasma
Compound data as published by MCM SpA. evolast® is a registered trademark of MCM SpA.
