Systems and methods for ex-situ bakeout of differentially pumped vacuum chambers

Patent metadata

Field	Value
Publication number	US-12594619-B2
Application number	US-202519091421-A
Country	US
Kind code	B2
Filing date	Mar 26, 2025
Priority date	May 3, 2024
Publication date	Apr 7, 2026
Grant date	Apr 7, 2026

Abstract

The system includes a high vacuum chamber, a bakeout chamber, and an ultra-high vacuum (UHV) chamber that is configured to be removably disposed on the high vacuum chamber and the bakeout chamber. The system further includes a heating element configured to heat the UHV chamber and desorb water vapor from the UHV chamber with the UHV chamber disposed on the bakeout chamber, and a gas source configured to supply a backfill gas to the UHV chamber disposed on the bakeout chamber. The system further includes a bakeout vacuum pump configured to extract the water vapor from the UHV chamber with the UHV chamber disposed on the bakeout chamber, and a high vacuum pump configured to extract the backfill gas from the UHV chamber with the UHV chamber disposed on the high vacuum chamber.

First claim

What is claimed is:

1 . A system comprising:
an ultra-high vacuum (UHV) chamber including a differential aperture; a high vacuum chamber, wherein the UHV chamber is configured to be removably disposed on the high vacuum chamber, such that the UHV chamber is in fluid communication with the high vacuum chamber via the differential aperture; a high vacuum pump configured to produce a high vacuum pressure in the UHV chamber; a bakeout chamber, wherein the UHV chamber is configured to be removably disposed on the bakeout chamber, such that the UHV chamber is in fluid communication with the bakeout chamber via the differential aperture; a bakeout vacuum pump configured to produce a vacuum pressure in the bakeout chamber and the UHV chamber with the UHV chamber disposed on the bakeout chamber; a heating element configured to heat the UHV chamber and desorb water vapor from the UHV chamber with the UHV chamber disposed on the bakeout chamber, wherein the bakeout vacuum pump or the high vacuum pump is further configured to extract the water vapor from the UHV chamber; and a gas source configured to supply a backfill gas to the UHV chamber disposed on the bakeout chamber, and the high vacuum pump is further configured to extract the backfill gas from the UHV chamber with the UHV chamber disposed on the high vacuum chamber.

2 . The system of claim 1 , further comprising:
a chuck disposed in the high vacuum chamber, wherein the chuck is configured to support a workpiece; and an electron source disposed in the UHV chamber, wherein the electron source is configured to emit an electron beam through the differential aperture directed onto the workpiece.

3 . The system of claim 1 , further comprising:
a mechanical hoist configured to remove the UHV chamber from the high vacuum chamber and dispose the UHV chamber on the bakeout chamber, wherein the UHV chamber is filled with the backfill gas as the mechanical hoist moves the UHV chamber from the bakeout chamber to the high vacuum chamber.

4 . The system of claim 1 , further comprising:
a flange cover configured to be removably disposed on the high vacuum chamber and configured to seal the high vacuum chamber as the UHV chamber is removed from the high vacuum chamber.

5 . The system of claim 1 , wherein the backfill gas comprises Ar or N 2 .

6 . The system of claim 1 , wherein the UHV chamber further includes a bypass valve that is movable between an open position and a closed position, such that in the open position, the UHV chamber disposed on the high vacuum chamber is in fluid communication with the high vacuum chamber via the bypass valve and the UHV chamber disposed on the bakeout chamber is in fluid communication with the bakeout chamber via the bypass valve.

7 . The system of claim 6 , further comprising:
a UHV pump configured to produce a UHV pressure in the UHV chamber with the bypass valve in the closed position.

8 . The system of claim 6 , wherein the gas source is configured to supply the backfill gas to the UHV chamber via the bakeout chamber through the bypass valve in the open position.

9 . The system of claim 1 , wherein the gas source is configured to supply the backfill gas directly to the UHV chamber.

10 . The system of claim 1 , wherein the heating element is a conductive heating element disposed within the bakeout chamber.

11 . The system of claim 1 , wherein the heating element is a radiant heating element disposed within the bakeout chamber.

12 . A method comprising:
pumping, with a bakeout vacuum pump, a bakeout chamber and an ultra-high vacuum (UHV) chamber to a vacuum pressure, wherein the UHV chamber includes a differential aperture, and the UHV chamber is in fluid communication with the bakeout chamber via the differential aperture as the UHV chamber is removably disposed on the bakeout chamber; heating, with a heating element, the UHV chamber to desorb water vapor from the UHV chamber; extracting, with the bakeout vacuum pump, the water vapor from the UHV chamber; and supplying, with a gas source, a backfill gas to the UHV chamber.

13 . The method of claim 12 , wherein before pumping the bakeout chamber and the UHV chamber to the vacuum pressure, the method further comprises:
removing, with a mechanical hoist, the UHV chamber from a high vacuum chamber, wherein the UHV chamber is in fluid communication with the high vacuum chamber via the differential aperture as the UHV chamber is removably disposed on the high vacuum chamber; and disposing, with the mechanical hoist, the UHV chamber onto the bakeout chamber.

14 . The method of claim 13 , wherein after supplying the backfill gas to the UHV chamber, the method further comprises:
removing, with the mechanical hoist, the UHV chamber from the bakeout chamber; and disposing, with the mechanical hoist, the UHV chamber onto the high vacuum chamber.

15 . The method of claim 14 , wherein after disposing the UHV chamber onto the high vacuum chamber, the method further comprises:
extracting, with a high vacuum pump, the backfill gas from the UHV chamber.

16 . The method of claim 15 , wherein after extracting the backfill gas from the UHV chamber, the method further comprises:
pumping, with a UHV pump, the UHV chamber to a UHV pressure.

17 . The method of claim 14 , further comprising:
disposing a flange cover on the high vacuum chamber to seal the high vacuum chamber after the UHV chamber is removed from the high vacuum chamber.

18 . The method of claim 17 , wherein before disposing the UHV chamber onto the high vacuum chamber, the method further comprises:
removing the flange cover from the high vacuum chamber.

19 . The method of claim 12 , wherein the UHV chamber further includes a bypass valve that is movable between an open position and a closed position, the UHV chamber being in fluid communication with the bakeout chamber via the bypass valve in the open position as the UHV chamber is removably disposed on the bakeout chamber, and after supplying the backfill gas to the UHV chamber, the method further comprises:
moving the bypass valve to the closed position to seal the backfill gas within the UHV chamber.

20 . The method of claim 12 , wherein the backfill gas comprises Ar or N 2 .

Assignees

• Kla Corp

Inventors

• Petrone Nicholas
• Muray Lawrence

Classifications

• B23K15/08

  Removing material, e.g. by cutting, by hole drilling · CPC title

• B23K2101/36

  Electric or electronic devices · CPC title

• B23K15/06 Primary

  within a vacuum chamber (B23K15/04 takes precedence) · CPC title