Removable bombardment filament-module for electron beam projection systems

An electron gun system including:

• an electron gun enclosure, with a feed-through element extending through a wall of said electron gun enclosure,
• an electron beam generating element housed within a filament module housing which is contained within said electron gun enclosure, said electron beam generating element being connected to said feed-through element,
• an electron column including a column top plate and column walls, said column top plate including an aperture therethrough for an electron beam, and said gun enclosure being located above the column top plate,
• said gun enclosure being located above the column top plate,
• a port in said gun enclosure, said port including means for permitting direct removal of and replacement of said feed-through element through said port and for permitting removal of said filament module housing without opening said electron column,
• said electron beam generating element and said filament module housing being accessible through said port into a chamber connected to said electron gun enclosure with said chamber having a chamber top plate, and
• means being provided above said column top plate for venting said chamber to prevent introduction of contaminating gases into said gun during removal of said filament module housing.

An electron gun system including:

• an electron gun enclosure, with a feed-through element extending through a wall of said electron gun enclosure,
• an electron beam generating element housed within a filament module housing which is contained within said electron gun enclosure, said electron beam generating element being connected to said feed-through element,
• an electron column including a column top plate and column walls, said column top plate including an aperture therethrough for an electron beam, and said gun enclosure being located above the column top plate,
• said gun enclosure being located above the column top plate,
• a port in said gun enclosure, said port including means for permitting direct removal of and replacement of said feed-through element through said port and for permitting removal of said filament module housing without opening said electron column,
• said electron beam generating element comprises a filament producing a primary electron beam directed at the back side of a cathode, said cathode being located between said electron beam generating element and an aperture in an electron beam column, and said cathode comprising means for providing a secondary electron beam in said electron beam column,
• means for rapidly and automatically connecting said filament module housing and said feed-through element electrically,
• a load-lock aligned with said electron column is provided on said gun as an access to said port, and
• a vent is provided between valve elements of said load-lock.

A method for separate removal of a feed-through element and a filament module housing from an electron gun enclosure which provides an electron beam to an electron column, said feed-through element extending through a wall of said electron gun enclosure, and said filament module housing being contained within said gun connected to said feed-through element, comprising the steps of

• providing a barrier between said column and said gun with an aperture for admission of an electron beam from said gun into said column, and
• directly removing and replacing said feed-through element through an access port in said wall of said gun and separate removal of said filament module housing through said port
• providing said filament module housing and said feed-through element with spring-biased elements for automatically interconnecting electrically for quick installation and removal of said feed-through element from contact with said filament module housing, and
• providing mounting means secured to said electron gun enclosure for supporting said filament module housing without fasteners within said electron gun enclosure.