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Product Briefing Outline: Ferrotec Corporation has made improvements to the standard ferrofluid magnetic liquids which provide the core sealing function in Ferrotec's ‘Ferrofluidic' vacuum rotary feedthroughs. Ferrotec vacuum feedthroughs are used in semiconductor manufacturing equipment, vacuum chambers, and other clean and controlled process environments. Ferrotec claims the new liquid improvements have reduced operating torque, reduced vapor pressure, and provided better thermal stability in demanding process environments.

Problem: A Ferrofluidic seal uses magnetic liquid and a permanent magnet to form a dynamic "o-ring" around a rotating shaft. This o-ring forms a barrier between the atmosphere and the process side of vacuum, ultra-clean, or aggressive gas environments. Depending upon the application where the vacuum rotary feedthrough is being used, the quality and the attributes of the ferrofluid used inside the seal can affect the performance characteristics of the seal.

Solution: Ferrotec's enhanced ferrofluid is offered in two options, for standard environments and for reactive gasses. Standard ferrofluid delivers optimal performance in most vacuum or non-reactive gas applications. Ferrotec's reactive gas ferrofluid trades higher viscosity and increased seal torque for improved performance in more demanding environments, such as ultra-high vacuum (UHV) use, high temperatures, and applications that expose the seal to aggressive or reactive gasses. With one-third less viscosity than the previous generation of standard ferrofluid, the improved standard ferrofluid offers vacuum feedthrough users reduced start-up torque, improved thermal stability, and reduced vapor pressure. For reactive gas applications, the improved reactive gas fluid offers dramatically increased thermal stability and vapor pressure has been reduced by an order of magnitude.

Applications: Wide range of sealing applications within process tools, gas systems etc...

Platform: Ferrotec's new ferrofluids are available in all standard Ferrotec vacuum rotary feedthroughs. Ferrofluids are a unique class of material. A ferrofluid is a stable colloidal suspension of sub-domain magnetic nano particles in a liquid carrier. The particles, which have an average size of about 100Å (10nm), are coated with a stabilizing dispersing agent (surfactant) which prevents particle agglomeration even when a strong magnetic field gradient is applied to the ferrofluid.

Availability: July 2006 onwards.