US 4,524,261 A · Localized vacuum processing apparatus

Abstract

Localized vacuum envelope apparatus includes a housing member having a bottom plate with a downwardly extending first sleeve and an upwardly extending flange. The flange includes ports for vacuum pumping and is adapted for attachment to an electron beam column. The apparatus further includes a lower plate having a second downwardly extending sleeve and an upper plate having a third downwardly extending sleeve. The first, second and third sleeves, which can have a truncated conical shape and are concentric, define vacuum zones. Channels are provided for connecting the vacuum zones to individual ports. The tips of the sleeves are coplanar and form the tip of the vacuum envelope. A noncontacting graded vacuum seal is formed between the tip of the vacuum envelope and a workpiece. The housing member and the upper plate can be ferromagnetic material to provide double magnetic shielding.

Claims25

Dependent claims

Apparatus adapted for attachment to a vacuum processing chamber for localized vacuum processing of a workpiece, said apparatus comprising:

a housing member including a bottom plate with a downwardly extending first sleeve having an aperture therethrough and an upwardly extending flange around the periphery of said plate, said flange including a plurality of ports for vacuum pumping, said bottom plate and said flange in combination defining an interior region of said housing member;
a lower plate mounted in said interior region of said housing member with a second sleeve extending downwardly into said aperture inside said first sleeve and having a tip coplanar with the tip of said first sleeve such that a first vacuum zone is defined between said first sleeve and said second sleeve and said first vacuum zone is in gas communication with a first one of said ports through a channel between said housing member and said lower plate;
and
an upper plate mounted above said lower plate in said interior region of said housing member with a third sleeve extending downwardly into said aperture inside said second sleeve and having a tip coplanar with the tips of said first and second sleeves such that a second vacuum zone is defined between said second sleeve and said third sleeve and a high vacuum zone is defined inside said third sleeve, said second vacuum zone being in gas communication with a second one of said ports through a second channel between said lower plate and said upper plate and said high vacuum zone being in gas communication with a third one of said ports through the portion of said interior region above said upper plate.

1 more element

Apparatus for localized vacuum processing of a workpiece, said apparatus comprising:

a first housing portion defining a vacuum chamber and means for evacuating said chamber;
a second housing portion including a bottom plate with a downwardly extending first sleeve having an aperture therethrough and an upwardly extending peripheral flange, said flange including ports for vacuum pumping;
a lower plate mounted in said second housing portion with a second sleeve extending downwardly into said aperture inside said first sleeve and having a tip coplanar with the tip of said first sleeve such that a first vacuum zone is defined between said first sleeve and said second sleeve and said first vacuum zone is in gas communication with a first one of said ports through a conduit between said second housing portion and said lower plate;
and
an upper plate mounted above said lower plate in said second housing portion with a third sleeve extending downwardly into said aperture inside said second sleeve and having a tip coplanar with the tips of said first and second sleeves such that a second vacuum zone is defined between said second sleeve and said third sleeve, said second vacuum zone being in gas communication with a second one of said ports through a second conduit between said lower plate and said upper plate and a high vacuum zone is defined inside said third sleeve, said high vacuum zone being in gas communication with said vacuum chamber and with a third one of said ports, such that a vacuum region extends from said vacuum chamber through said high vacuum zone to a portion of the surface of said workpiece.

2 more elements

Apparatus for providing a graded radial vacuum in a gap through which a particle beam propagates along a longitudinal axis from the interior of a high vacuum envelope containing a source of the beam to a workpiece that is maintained at atmospheric pressure except for an area exposed to the graded radial vacuum, the apparatus comprising plural nested solid members having concentric sleeves with coplanar tips, the sleeves being coaxial with the beam axis at different radii from the beam axis to define plural fluid flow passages concentric with the beam axis, the coplanar tips being equispaced from the workpiece to define the gap, each solid member having a surface portion extending radially away from the beam axis, adjacent ones of said surface portions of different solid members defining a radially extending fluid conduit from the outer concentric fluid flow passage, the outermost one of said members having a wall carried by the envelope and supporting the remainder of said members, the wall having a port for providing a fluid path between a vacuum source and the outer concentric fluid flow passage through said fluid conduit, the vacuum source having a lower vacuum than the high vacuum in the envelope, the center concentric fluid flow passage being in a direct fluid flow path with the envelope interior and maintained approximately at the pressure of the envelope interior.

Dependencies are inferred from the claim text.

Localized vacuum processing apparatus

Life of this patent

Localized vacuum processing apparatus

Life of this patent

Abstract

Claims25