US-20260124715-A1 - POLISHING SYSTEM FOR SEMICONDUCTING WAFER SUBSTRATES

Abstract

A slurry arm for an associated chemical mechanical polishing (CMP) system for semiconducting wafer substrates includes a slurry arm main body; a plurality of holes disposed along a length of the slurry arm main body; a valve controlling slurry flow through each hole of the plurality of holes; and a controller configured to open or close each valve.

Inventors

• Jui Yu PAI
• Chen-hsueh Lin
• Tang-Kuei Chang
• Jeng-Chi Lin
• Chi-hsiang Shen
• Fang-I Chih
• Te-Chien Hou

Assignees

• TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY, LTD.

Dates

Publication Date

20260507

Application Date

20241107

Claims (20)

1. 1 . A slurry arm for an associated chemical mechanical polishing (CMP) system for semiconducting wafer substrates, the slurry arm comprising: a slurry arm main body; a plurality of holes disposed along a length of the slurry arm main body; at least one valve controlling slurry flow through each hole of the plurality of holes; and a controller configured to open or close each valve.
2. 2 . The slurry arm of claim 1 , wherein each valve comprises a pair of gates, each gate being positioned at opposite sides of the valve and configured to move laterally relative to each other.
3. 3 . The slurry arm of claim 2 , wherein the gates for each valve are continuously movable between an open state and a closed state, the gates being retractable within a portion of the slurry arm main body.
4. 4 . The slurry arm of claim 1 , wherein one valve is present for each hole in the plurality of holes.
5. 5 . The slurry arm of claim 1 , wherein each valve comprises a hydrophilic material.
6. 6 . The slurry arm of claim 1 , wherein each valve comprises a hydrophobic material.
7. 7 . The slurry arm of claim 6 , wherein the hydrophobic material comprises an acrylic resin, epoxy resin, polyethylene, polystyrene, polyvinyl Chloride, polytetrafluoroethylene, polydimethylsiloxane, polyester, or polyurethane, or combinations thereof.
8. 8 . The slurry arm of claim 1 , wherein each hole has a length of about 0.1 centimeters (cm) to about 5.0 cm, a width of about 0.1 cm to about 5.0 cm, and a thickness of about 0.1 cm to about 5.0 cm.
9. 9 . The slurry arm of claim 1 , wherein each valve has a cross-sectional shape comprising a triangle, a rectangle, a circle, a hexagon, a trapezoid, or a heptagon.
10. 10 . The slurry arm of claim 1 , wherein the controller is configured to selectively open or close the at least one valve based on at least one user input.
11. 11 . A method of performing chemical mechanical planarization (CMP), comprising: measuring a profile of a wafer substrate; determining a desired configuration of a plurality of valves controlling slurry flow to a plurality of holes disposed along a length of the a slurry arm, the desired configuration comprising each of the valves in an open state, a semi-open state, or a closed state; flowing slurry through the slurry arm towards the plurality of holes; and depositing slurry upon a polishing pad.
12. 12 . The method of claim 11 , further comprising: after measuring the profile of the wafer substrate, determining a current configuration of the plurality of valves; and after determining the desired configuration, setting each valve to obtain the desired configuration.
13. 13 . The method of claim 12 , wherein the steps of measuring the profile of the wafer substrate, determining the current configuration of the plurality of valves, determining the desired configuration of a plurality of valves, and setting each valve to obtain the desired configuration are continuously repeated.
14. 14 . A chemical mechanical polishing (CMP) system for semiconducting wafer substrates, comprising: a polishing pad mounted upon a platen; a wafer carrier that can be positioned above the polishing pad; and a slurry arm for depositing slurry upon the polishing pad, comprising: a plurality of holes disposed along a length thereof; a plurality of valves, wherein each hole has a corresponding valve; and a controller configured to control movement of each valve of the plurality of valves.
15. 15 . The CMP system of claim 14 , wherein each valve comprises a pair of gates, each gate being positioned at opposite sides of the valve and configured to move laterally relative to each other.
16. 16 . The CMP system of claim 15 , wherein the gates for a corresponding valve are continuously movable between an open state and a closed state, the gates being retractable within a portion of the slurry arm.
17. 17 . The CMP system of claim 14 , wherein each gate comprises one of a hydrophilic material or a hydrophobic material.
18. 18 . The CMP system of claim 14 , wherein each hole has a length of about 0.1 centimeters (cm) to about 5.0 cm, a width of about 0.1 cm to about 5.0 cm, and a thickness of about 0.1 cm to about 5.0 cm.
19. 19 . The CMP system of claim 14 , wherein a number of valves in the plurality of valves is different from a number of holes in the plurality of holes.
20. 20 . The CMP system of claim 14 , wherein the slurry arm further comprises a plurality of supply tubes, each supply tube configured to provide slurry to at least one hole in the plurality of holes.

Description

BACKGROUND Chemical mechanical polishing (“CMP”) is used in the manufacture of integrated circuits. A combination of chemical and mechanical forces is used to provide a level surface on a layer of a semiconducting wafer substrate. BRIEF DESCRIPTION OF THE DRAWINGS Aspects of the present disclosure are best understood from the following detailed description when read with the accompanying figures. It is noted that, in accordance with the standard practice in the industry, various features are not drawn to scale. In fact, the dimensions of the various features may be arbitrarily increased or reduced for clarity of discussion. FIG. 1A is a side view of a CMP system, in accordance with some embodiments of the present disclosure. FIG. 1B is a plan view of the CMP system showing only some components. FIG. 1C is a plan view of another embodiment of a CMP system, in accordance with some embodiments of the present disclosure. Here, one polishing pad can be used with two wafer carriers to polish two wafer substrates simultaneously. FIG. 2 is a simplified side view of the CMP system, focusing on the polishing pad and the slurry arm. FIG. 3 is a simplified perspective view of the CMP system, focusing on the slurry arm. FIG. 4A is a side view of a gate of a valve of the CMP system in a closed state. FIG. 4B is a side view of a gate of a valve of the CMP system in an open state. FIG. 4C is a side view of a gate of a valve of the CMP system in a semi-open state. FIGS. 5A-5F show different shapes of holes and valves of the CMP system. FIG. 6 is a plan view of a slurry arm with a configuration of open and closed holes. FIGS. 7A-7P show different combinations of open and closed holes for the slurry arm. FIG. 8A is a perspective view of a first example configuration of holes for slurry output through the slurry arm. FIG. 8B is a perspective view of a second example configuration of holes for slurry output through the slurry arm. FIG. 8C is a perspective view of a third example configuration of holes for slurry output through the slurry arm. FIG. 9 is a schematic cross-sectional plan view of the slurry arm where all holes are supplied with slurry by a single supply tube within the slurry arm. FIG. 10 is a schematic cross-sectional plan view of the slurry arm where all holes are supplied with slurry by different supply tubes within the slurry arm. FIG. 11A is a schematic perspective view of the slurry arm where slurry exits the slurry arm via holes on the bottom of the slurry arm. FIG. 11B is a cross-sectional plan view of the slurry arm of FIG. 11A. FIG. 12A is a schematic perspective view of the slurry arm where slurry exits the slurry arm via holes on one side of the slurry arm. FIG. 12B is a cross-sectional plan view of the slurry arm of FIG. 12A. FIG. 13A is a schematic perspective view of the slurry arm where slurry exits the slurry arm via holes on both sides of the slurry arm. FIG. 13B is a cross-sectional plan view of the slurry arm of FIG. 13A. FIG. 14 is a flow chart illustrating a method for performing CMP, in accordance with some embodiments. FIG. 15A is a side view of a substrate with two layers thereon, prior to CMP. FIG. 15B is a side view of a substrate with two layers thereon, after CMP has planarized the top layer. DETAILED DESCRIPTION The following disclosure provides many different embodiments, or examples, for implementing different features of the provided subject matter. Specific examples of components and arrangements are described below to simplify the present disclosure. These are, of course, merely examples and are not intended to be limiting. For example, the formation of a first feature over or on a second feature in the description that follows may include embodiments in which the first and second features are formed in direct contact, and may also include embodiments in which additional features may be formed between the first and second features, such that the first and second features may not be in direct contact. In addition, the present disclosure may repeat reference numerals and/or letters in the various examples. This repetition is for the purpose of simplicity and clarity and does not in itself dictate a relationship between the various embodiments and/or configurations discussed. Further, spatially relative terms, such as “beneath,” “below,” “lower,” “above,” “upper” and the like, may be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. The spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. The apparatus may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein may likewise be interpreted accordingly. Numerical values in the specification and claims of this application should be understood to include numerical v