Vacuum-Break Filters

Developed in cooperation with Tokyo Electron, the break filter uses the extremely fine pores of porous ceramic material to produce a gas flow control diffuser in breaking a vacuum by utilizing the pressure buffer effect. Traditionally, to break a vacuum in a load lock chamber, nitrogen gas was slowly introduced into the chamber in a slow vent process in order to prevent particle dispersion. Simply installing a break filter to the nitrogen gas vent port of the load lock chamber improves the throughput by eliminating the need for slow venting. It also reduces atmospheric particle counts by preventing particle dispersion.

The effect of a break filter

These photographs show what happens when a vacuum is broken in an approximately 11-liter chamber - one without a break filter but with approximately 60 seconds of slow venting; and the other with a break filter that breaks the vacuum in 20 seconds, without slow venting. The white spots are styrofoam, which represents particles.

With filter
Image of With filter
Without slow venting

Without filter
Image of Without filter
With slow venting

It is observed that attaching a break filter restricts the particle scattering to a minimum. The break filter can be used to improve throughput in vacuum devices to cut down particle generation and prevent the sporadic generation of particles.

Image of Break Filters
Break Filters

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