Turbine cap for turbo-molecular pump

摘要

A turbine assembly mounted to a pump rotor via mounting bolts. The turbine includes fins extending therefrom for pumping gasses and suspended particles from a semiconductor processing chamber. The tops of the bolts are recessed from the top surface of the turbine in a bolt cavity having an open end. A cap member is mounted over and seals the open end of the bolt cavity via a center bolt. The cap member has a shaped upper surface (conical, parabolic, squared, rounded) for deflecting particles away from the center of the turbine and toward the turbine's fins. The cap member's upper surface can include particle deflecting features such as fins, channels or asymmetric shapes to enhance particle deflection as the cap member rotates. The cap member can include a compressible o-ring for a friction fit mounting to the turbine.

主权项

1. A turbine cap assembly comprising:
a turbo molecular turbine cap member configured to spin with a turbo molecular turbine, the turbo molecular turbine cap member having a first cap threaded hole that does not extend through the entire turbo molecular turbine cap and a first portion with a first circumference,
wherein the turbo molecular turbine cap member includes a vent channel through the turbo molecular turbine cap member for venting air, the vent channel being parallel to the first cap threaded hole and positioned between an outer edge of the turbo molecular turbine cap member and the first cap threaded hole; a plate member having a second circumference and a second plate hole; an o-ring disposed between the turbo molecular turbine cap member and plate member, and having a third circumference; and a threaded bolt extending through the second plate hole and threaded into the first cap threaded hole, wherein a distance between the turbo molecular turbine cap member and the plate member is adjustable by rotation of the threaded bolt between a first position in which the o-ring is compressed by the turbo molecular turbine cap member and the plate member and a second position in which the o-ring is not compressed by the turbo molecular turbine cap member and the plate member.