US-12624446-B2 - Pumping liners with self-adjusting pumping conductance

US12624446B2US 12624446 B2US12624446 B2US 12624446B2US-12624446-B2

Abstract

Pump liners and process chambers with the pump liners are described. The pump liner has a ring-shaped body with an annular wall enclosing a process region. A plurality of circumferentially spaced openings provide fluid communication through the annular wall between the process region and a region outside of the ring-shaped body. Each of the plurality of circumferentially spaced openings has a self-adjusting valve assembly. Self-adjusting valves and processing methods are also described.

Inventors

Muhannad MUSTAFA
Muhammad M. Rasheed

Assignees

APPLIED MATERIALS, INC.

Dates

Publication Date: 20260512
Application Date: 20220509

Claims (16)

1 . A pump liner for a process chamber, the pump liner comprising: a ring-shaped body having an annular wall enclosing a process region, the annular wall having an inner peripheral surface, an outer peripheral surface, an upper portion, and a lower portion; a plurality of circumferentially spaced openings extending completely through the annular wall and providing fluid communication through the annular wall between the process region and a region outside of the ring-shaped body; and a plurality of self-adjusting valve assemblies, each of the plurality of circumferentially spaced openings having a self-adjusting valve assembly in contact with the outer peripheral surface of the annular wall, wherein each of the plurality of self-adjusting valve assemblies is configured to provide a substantially uniform pressure outside of the pump liner by self-adjusting to an open position when a pressure and a flow through the plurality of self-adjusting valve assemblies are the same and by self-adjusting to a sealed position when the pressure and/or the flow through the plurality of self-adjusting valve assemblies is imbalanced, wherein the self-adjusting valve assembly comprises: a valve housing having a sidewall and a distal end wall, the sidewall having an inner sidewall surface and an outer sidewall surface, the distal end wall having an inner end wall surface, an outer end wall surface and an aperture formed through the distal end wall; an inner cylinder within the valve housing, the inner cylinder having an inner cylinder sidewall with a cavity, the inner cylinder sidewall having an inner cylinder outer sidewall surface spaced from the inner sidewall surface of the valve housing to provide a flow path, and an inner cylinder inner sidewall surface bounding the cavity; a compression element within the cavity of the inner cylinder; and a slidable gate within the cavity of the inner cylinder, the slidable gate connected to the compression element and aligned with the aperture in the valve housing, wherein the compression element is configured to move the slideable gate between a full flow position allowing a flow of gas through the flow path and a sealed position preventing gas from flowing through the flow path, and the slidable gate moves in substantially an opposite direction from the flow of gas through the flow path.
2 . The pump liner of claim 1 , wherein the valve housing has a proximal end adjacent the outer peripheral surface of the annular wall.
3 . The pump liner of claim 2 , wherein the slidable gate is configured to contact the distal end wall of the valve housing adjacent the aperture to form a fluid-tight seal.
4 . The pump liner of claim 2 , wherein the inner cylinder has a flange at a proximal end of the inner cylinder, the flange having a proximal face and a distal face.
5 . The pump liner of claim 4 , wherein a proximal surface of the proximal end of the valve housing contacts the distal face of the flange.
6 . The pump liner of claim 4 , wherein the flange of the inner cylinder comprises a center opening with a plurality of outer openings positioned around the center opening.
7 . The pump liner of claim 6 , wherein the plurality of outer openings is aligned to allow a flow of fluid to pass through the flange into the flow path, and the center opening is aligned with the cavity in the inner cylinder to allow gas pressure from the process region to move the slidable gate.
8 . The pump liner of claim 1 , wherein the compression element comprises a spring.
9 . The pump liner of claim 1 , wherein each of the compression elements has a substantially same spring force constant.
10 . The pump liner of claim 1 , wherein the inner cylinder outer sidewall surface is spaced from the inner sidewall surface of the valve housing by an amount in the range of 0.5 inches to 0.8 inches.
11 . The pump liner of claim 1 , wherein the valve housing has a length in the range of 0.75 inches to 2 inches.
12 . The pump liner of claim 1 , wherein the ring-shaped body further comprises: a lower channel in the lower portion of the annular wall separated from an annular upper channel by a partition, the lower channel in fluid communication with the annular upper channel through at least one passage in the partition, and a slit valve opening in the lower portion of the annular wall extending from the inner peripheral surface to the outer peripheral surface.
13 . The pump liner of claim 1 , wherein there are in the range of 4 to 256 of the plurality of circumferentially spaced openings.
14 . The pump liner of claim 13 , wherein the plurality of circumferentially spaced openings are evenly spaced.
15 . A self-adjusting valve assembly comprising: a valve housing having a sidewall and a distal end wall, the sidewall having an inner sidewall surface and an outer sidewall surface, the distal end wall having an inner end wall surface, an outer end wall surface, and an aperture formed through the distal end wall; an inner cylinder within the valve housing, the inner cylinder having an inner cylinder sidewall with a cavity, the inner cylinder sidewall having an inner cylinder outer sidewall surface spaced from the inner sidewall surface of the valve housing to provide a flow path, and an inner cylinder inner sidewall surface bounding the cavity; a compression element within the cavity of the inner cylinder; and a slidable gate within the cavity of the inner cylinder, the slidable gate connected to the compression element and aligned with the aperture in the valve housing, wherein the compression element is configured to move the slidable gate between a full flow position allowing a flow of gas through the flow path and a sealed position preventing gas from flowing through the flow path, and the slidable gate moves in sustainably an opposite direction from the flow of gas through the flow path.
16 . The pump liner of claim 1 , wherein a flow conductance of the pump liner is self-adjusting using spring actuation and a local pressure difference in each valve assembly.

Description

CROSS-REFERENCE TO RELATED APPLICATION This application claims priority to U.S. Provisional Application No. 63/186,162, filed May 9, 2021, the entire disclosure of which is hereby incorporated by reference herein. TECHNICAL FIELD Embodiments of the present disclosure pertain to the field of electronic device manufacturing. More particularly, embodiments of the disclosure are directed to apparatus to improve flow control in processing chambers. BACKGROUND Various processing chambers, for example, Atomic Layer Deposition (ALD) and Chemical Vapor Deposition (CVD) chambers use a pump liner to confine the reactive gases to a reaction space adjacent the substrate surface. The pump liners help contain gases within the reaction space and allow rapid evacuation of gases from the reaction space. The pump liners include a plurality of openings to allow the reaction gases to flow through the liner to exhaust. The pump ports are closer to some of the openings than to others. For example, where the pump port is on one side of the ring-shaped liner, the openings in the liner immediately adjacent the pump port are closer than the openings on the opposite side of the liner. To compensate for the different distances, current processing chamber liners have variable size openings to choke the flow of gases toward the pumping ports. The openings closest to the pump port are smaller than the openings further away from the pump port. Most processing chambers have asymmetric pumping since fore lines are located off-axis with respect to the process chamber. Some processes are highly sensitive to flow uniformity around the wafer. Therefore, pumping liner hole size optimization is a popular idea to improve flow uniformity around the wafer. Pumping liner hole sizes, e.g., diameter, are commonly optimized to change flow conductance based on simulation or actual wafer deposition mapping. Individualized pumping liner designs are expensive, have large lead times and need trial- and error tests. Even with the individualized approach, achieving pumping liner uniformity remains a goal rather than reality. Therefore, there is a need in the art for apparatus and methods for providing a uniform flow of gases in the process volume. SUMMARY One or more embodiments of the disclosure are directed to pump liners for process chambers. The pump liners comprise a ring-shaped body with an annular wall enclosing a process region. The annular wall has an inner peripheral surface and an outer peripheral surface, an upper portion and a lower portion. A plurality of circumferentially spaced openings provide fluid communication through the annular wall between the process region and a region outside of the ring-shaped body. Each of the plurality of circumferentially spaced openings has a self-adjusting valve assembly. Additional embodiments of the disclosure are directed to pump liners for process chambers. The pump liners comprise a ring-shaped body with an annular wall enclosing a process region. The annular wall has an inner peripheral surface and an outer peripheral surface, an upper portion and a lower portion. A plurality of circumferentially spaced openings provide fluid communication through the annular wall between the process region and a region outside of the ring-shaped body. Each of the plurality of circumferentially spaced openings has a self-adjusting valve assembly comprising, a valve housing having a sidewall and a distal end wall, the sidewall having an inner sidewall surface and an outer sidewall surface, the distal end wall having an inner end wall surface and an outer end wall surface and an aperture formed through the distal end wall; an inner cylinder within the valve housing, the inner cylinder having an inner cylinder sidewall with a cavity, the inner cylinder sidewall having an inner cylinder outer sidewall surface spaced from the inner sidewall surface of the valve housing to provide a flow path, and an inner cylinder inner sidewall surface bounding the cavity; a compression element within the cavity of the inner cylinder; and a slidable gate within the cavity of the inner cylinder, the slidable gate connected to the compression element and aligned with the aperture in the valve housing, wherein the compression element is configured to move the slidable gate between a full flow position allowing a flow of gas through the flow path and a sealed position preventing gas from flowing through the flow path. Further embodiments of the disclosure are directed to self-adjusting valve assemblies comprising a valve housing, an inner cylinder, a compression element and a slidable gate. The valve housing has a sidewall and a distal end wall. The sidewall has an inner sidewall surface and an outer sidewall surface. The distal end wall has an inner end wall surface and an outer end wall surface and an aperture formed through the distal end wall. The inner cylinder is within the valve housing and has an inner cylinder sidewall with a cavity. The i