US-20260124647-A1 - FOAM NOZZLE CLEANING APPARATUS AND METHOD FOR CLEANING WAFER SURFACE

Abstract

The present disclosure relates to a foaming nozzle apparatus and method of cleaning a semiconductor wafer surface with a foaming cleaning agent. One or more foaming nozzle apparatuses can be included in a semiconductor processing chamber for cleaning debris from wafer surfaces.

Inventors

• Chi-hsiang Shen
• Te-Chien Hou
• Jeng-Chi Lin
• Jui Yu PAI
• Kei-Wei Chen
• Hui-Chi Huang
• Chih Hung Chen
• Tang-Kuei Chang

Assignees

• TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY, LTD.

Dates

Publication Date

20260507

Application Date

20241104

Claims (20)

1. 1 . A method of removing debris from one or more surfaces of a semiconductor wafer, the method comprising: rotating the semiconductor wafer; supplying a cleaning solution from a first source; supplying a mixture of water and gas from a second source; mixing the cleaning solution, water, and gas; forming a foaming cleaning agent from the mixture of the cleaning solution, water, and gas; dispersing the foaming cleaning agent on the one or more surfaces of the semiconductor wafer to allow the foaming cleaning agent to lift and suspend the debris over the one or more surfaces of the semiconductor wafer; and rinsing the foaming cleaning agent and debris from the one or more surfaces of the semiconductor wafer.
2. 2 . The method of claim 1 , wherein the cleaning solution comprises one or more surfactants.
3. 3 . The method of claim 1 , wherein the gas comprises an inert gas selected from nitrogen, helium, neon, argon, or xenon.
4. 4 . The method of claim 1 , wherein the cleaning solution is supplied at a rate of 0.01 to 20 liters/minute.
5. 5 . The method of claim 1 , wherein the semiconductor wafer is rotated in a vertical orientation.
6. 6 . The method of claim 1 , wherein the semiconductor wafer is rotated in a horizontal orientation.
7. 7 . The method of claim 1 , wherein the semiconductor wafer is rotated inside a semiconductor polishing or semiconductor cleaning chamber.
8. 8 . The method of claim 1 , further comprising: scrubbing the foaming cleaning agent on the one or more surfaces of the semiconductor wafer with one or more brushes.
9. 9 . The method of claim 1 , wherein the foaming cleaning agent is dispersed from a first nozzle facing a first surface of the semiconductor wafer and a second nozzle facing a second surface of the semiconductor wafer opposite the first surface.
10. 10 . A method of cleaning a semiconductor wafer, comprising: placing the semiconductor wafer on a polishing pad in a polishing chamber; rotating the polishing pad; applying a slurry on the polishing pad to remove a portion of a surface of the semiconductor wafer, wherein the removed portion comprises debris; dispersing a foaming cleaning agent on the surface of the semiconductor wafer to allow the foaming cleaning agent to lift and suspend the debris over the surface of the semiconductor wafer; and rinsing the foaming cleaning agent and debris from the surface of the semiconductor wafer.
11. 11 . The method of claim 10 , wherein the foaming cleaning agent comprises at least one surfactant.
12. 12 . The method of claim 10 , wherein the polishing pad is rotated at a speed of 500 rpm or less.
13. 13 . The method of claim 10 , wherein the slurry is applied through a slurry arm disposed over the polishing pad.
14. 14 . The method of claim 10 , wherein the foaming cleaning agent is dispersed through a plurality of nozzles.
15. 15 . The method of claim 10 , wherein the semiconductor wafer is placed on the polishing pad by a polishing head.
16. 16 . The method of claim 10 , wherein the foaming cleaning agent has a viscosity between 100 and 10,000 centipoise.
17. 17 . An apparatus for removing debris from a semiconductor wafer, comprising: a plurality of grooved rollers configured to rotate the semiconductor wafer; at least one foam source configured to disperse a foaming cleaning agent; at least one scrubbing brush configured to scrub at least one surface of the semiconductor wafer; and at least one spray bar configured to rinse the semiconductor wafer.
18. 18 . The apparatus of claim 17 , wherein the at least one scrubbing brush comprises a nylon or polyvinyl acetate (PVA).
19. 19 . The apparatus of claim 17 , wherein the at least one spray bar includes a plurality of nozzles.
20. 20 . The apparatus of claim 17 , wherein the at least one foam source is configured to disperse the foaming cleaning agent through a nozzle.

Description

BACKGROUND The processing of wafers to manufacture semiconductor devices includes multiple steps such as etching and cleaning processes to form features of the semiconductor device on the wafers. The etching processes involve the removal of material either directly from the wafers or layers formed on the wafers. The etching processes leave behind residual material which is removed during the cleaning processes. However, as the dimensions of semiconductor devices continue to scale down, trace amounts of debris or contaminants remaining behind in the trenches and vias are becoming increasingly difficult to remove. Some of the debris or contaminants are small particles. Conventional cleaning methods use wet spray and dispense methods in which the semiconductor substrate is rotated and a spray force is used to produce shear stress and turbulent flow for cleaning the debris or contaminants from sidewalls and bottoms of trenches and vias. Brushes can be used to scrub the surfaces of the wafer during cleaning to facilitate the removal of the contaminants. Wet spray cleaning methods, however, have their shortcomings. Feature patterns with a small pitch (e.g., less than 20 nm) can be easily collapsed by a strong shear force and a high wafer rotation rate. Further, the efficiency of removing debris or contaminants at the bottoms and/or on the sidewall of high aspect ratio trenches and vias may be very low. Remaining debris or contaminants can lead to corrosion on the wafer which reduces yield. Moreover, conventional wet spray cleaning methods can be expensive in that they consume large amounts of cleaning chemicals. During wet spray cleanings, the chemical leaves the wafer surface very quickly, especially when the wafer is vertically oriented during cleaning operations. Therefore, a large amount of the chemicals need to be sprayed onto the wafer during cleaning, which can increase costs. Accordingly, a need exists for an improved wafer cleaning method that does not have the shortcomings of traditional wet cleaning methods. 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 emphasized 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. FIGS. 1, 2, 3, and 4 are examples of a foaming nozzle apparatus in accordance with some embodiments of the present disclosure. FIGS. 5A, 5B, 5C, 5D, 5E, and 5F illustrate examples of wafer cleaning with the foaming nozzle apparatus according to embodiments of the present disclosure. FIGS. 6A and 6B illustrate examples of a wafer cleaning operation with the foaming nozzle apparatus according to other embodiments of the present disclosure. FIG. 7 illustrates an example of a cleaning operation with the foaming nozzle apparatus installed in a polishing chamber according to an embodiment of the present disclosure. FIG. 8 illustrates an example of a cleaning operation with the foaming nozzle apparatus installed in a polishing chamber according to another embodiment of the present disclosure. FIGS. 9A, 9B, 9C, 9D, 9E, 9F, 9G, 9H, 9I, 9J, 9K, 9L, 9M, 9N, 9O, 9P, 9Q, and 9R illustrate examples of nozzle apertures of the foaming nozzle apparatus according to embodiments of the present disclosure. FIG. 10 is a flowchart illustrating a cleaning method using the foaming nozzle apparatus in accordance with an embodiment of the present disclosure. FIG. 11 is a flowchart illustrating a cleaning method using the foaming nozzle apparatus in accordance with another embodiment of the present disclosure. DETAILED DESCRIPTION It is to be understood that the following disclosure provides many different embodiments, or examples, for implementing different features of the present application. Specific embodiments or 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, dimensions of elements are not limited to the disclosed range or values but may depend upon process conditions and/or desired properties of the device. Moreover, 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 by interposing the first and second features, such that the first and second features may not be in direct contact. Various features may be arbitrarily drawn in different scales for simplicity and clarity. In the accompanying drawings, some layers/features may be omitted for simplification. Further, spatially relative terms, such as “beneath,” “below,” “lower,” “above,” “upper” and the like, may be used herein for ea