Apparatus for shielding process chamber port

• US 7,685,965 B1
• Filed: 01/26/2006
• Issued: 03/30/2010
• Est. Priority Date: 01/26/2006
• Status: Active Grant

• Current Assignee: Lam Research Corporation
• Original Assignee: Lam Research Corporation
• Inventors: Daugherty, John E., Ronne, Allan K., Hao, Fangli J.
• Primary Examiner(s): Kackar; Ram N
• Assistant Examiner(s): Chen; Keath T
• Application Number:
  US11/341,079
• Time in Patent Office: 1,524 Days
• Field of Search: 118/723.I, 118/723.R
• US Class Current: 118/723.00I
• CPC Class Codes: H01J 37/32477 characterised by the means for protecting vessels or internal parts, e.g. coatings
• CPC Class Codes: H01J 37/32623 Mechanical discharge control means

Abstract

A port provides access to a process chamber interior for exemplary gas injection and process analysis and measurement. Centering the port in an external RF coil reduces the strength of an electric field across the port in generating plasma in the chamber. Plasma-induced etching and deposition in a bore of a gas injection injector mounted in the port is reduced by a grounded shield surrounding a region defined by the port, extending the life of the injector and of a chamber window in which the port is provided. The shield surrounds the region, and is configured with a longitudinally-extending slot defining a retainer arm and a flexure junction, and with a retainer foot on the arm. The junction urges the arm to extend the foot into a retainer groove of the port, and flexes to permit foot movement out of the groove in removal of the shield from the port.

Claims

1. A shield for protecting an access region of a process chamber window from an electric field that is generated adjacent to the process chamber window, the access region being defined by a port configured with a retainer groove on the sidewall of the port, the shield comprising:

a shield member fabricated from material adapted to substantially block the electric field from entering the access region of the process chamber window, wherein the access region is defined by the port that is configured with the retainer groove on the sidewall of the port, the shield member having a longitudinal axis, the shield member being configured to substantially surround the access region and further being configured with a longitudinally-extending slot defining a retainer arm being parallel to the longitudinally-extending slot and a flexure junction between the retainer arm and the shield member, wherein the longitudinally-extending slot is an opening and defines a U-shape, and wherein the retainer arm is within the U of the U-shape and the flexure junction is at the open end of the U of the U-shape, the retainer arm having a retainer foot and an arm-position control tab, the flexure junction being configured to normally position the retainer arm away from the longitudinal axis to adapt the retainer foot to extend into the retainer groove by using the arm-position control tab upon insertion of the shield member into the port, the flexure junction being further configured to permit movement of the retainer arm toward the longitudinal axis to adapt the retainer foot to move out of the retainer groove by using the arm-position control tab to permit removal of the shield member from the port, wherein the arm-position control tab is external to the port to facilitate manual flexure of the flexure junction to adapt the retainer foot to extend into and to move out of the retainer groove.

2. A shield as recited in claim 1, wherein:

the slot is a first slot, the arm is a first arm and the flexure junction is a first flexure junction; and

the shield member is further configured with at least one other longitudinally-extending slot to define at least one other retainer arm and at least one other flexure junction between the at least one other retainer arm and the shield member, the at least one other arm and the at least one other flexure junction being respectively configured corresponding to the respective first arm and first flexure junction.

3. A shield as recited in claim 1, wherein:

the shield member is further configured with a plurality of the longitudinally-extending slots, each of the slots defining one of the arms and one of the flexure junctions and one of the retainer feet; and

the shield member is further configured with the longitudinally-extending slots spaced around a perimeter of the shield.

4. A shield as recited in claim 3, wherein there are 3 longitudinally-extending slots.

5. A shield for protecting a process gas injector region from an electric field that is generated adjacent to a port in a process chamber window, the port being configured to receive a portion of the process gas injector region, the port being further configured with a shield retainer groove on the sidewall of the port, the shield comprising:

a shield member fabricated from material adapted to substantially block the electric field from entering the process gas injector region, wherein the port is configured to receive a portion of the gas process injector region and the port is further configured with the shield retainer groove on the sidewall of the port, the shield member having a longitudinal axis, the shield member being configured to substantially surround the process gas injector region and being further configured with a continuous slot defining a retainer arm extending parallel to the longitudinal axis and defining a flexure junction between the retainer arm and the shield member, wherein the continuous slot is an opening and defines a U-shape, and wherein the retainer arm being configured within the U of the U-shape and the flexure junction is at the open end of the U of the U-shape, the retainer arm having a retainer foot and an arm-position control tab, the flexure junction being configured to permit movement of the retainer arm toward the longitudinal axis to adapt the retainer foot to extend into the shield retainer groove by using the arm-position control tab to allow insertion of the shield member into the port, the flexure junction being further configured to normally position the retainer arm away from the longitudinal axis to adapt the retainer foot of the inserted shield member to extend into the shield retainer groove by using the arm-position control tab, the configuration of the flexure junction permitting movement of the retainer arm toward the longitudinal axis being effective to further adapt the retainer foot to move out of the shield retainer groove and permit removal of the shield member from the port, wherein the arm-position control tab is external to the port to facilitate manual flexure of the flexure junction to adapt the retainer foot to extend into and to move out of the shield retainer groove.

6. A shield as recited in claim 5, wherein:

the continuous slot is configured with parallel portions each having an end and extending parallel to the longitudinal axis, the ends being opposed to each other, the continuous slot being further configured with a transverse slot section connected to each of the opposed ends of the parallel portions of the continuous slot, the slot being further configured to interrupt eddy current flow induced by the electric field.

7. A shield as recited in claim 5, wherein:

the shield member is further configured with a plurality of continuous slots each defining one of the arms and one of the flexure junctions and one of the retainer feet.

8. A shield as recited in claim 7, wherein:

the respective plurality of continuous slots are spaced around a perimeter of the shield.

9. A shield as recited in claim 5, wherein:

the shield member is further configured with a plurality of the continuous slots, the slots being spaced around a perimeter of the shield.

10. A shield as recited in claim 9, wherein there are 3 continuous slots.