ACOUSTIC ENERGY SYSTEM, METHOD AND APPARATUS FOR PROCESSING FLAT ARTICLES

Abstract

A system, apparatus and method for processing this flat articles, such as semiconductor wafers, with acoustical energy. In a cleaning process, the inventive system, apparatus and method can remove particles from both sides of a wafer more efficiently and effectively. in one aspect, the invention is a system for processing flat articles comprising: a rotatable support for supporting a flat article; a first dispenser for applying liquid to a first surface of a flat article on the rotatable support; a second dispenser for applying liquid to a second surface of a flat article on the rotatable support; a first transducer assembly comprising a first transducer for generating acoustic energy and a first transmitter acoustically coupled to the first transducer, the first transducer assembly positioned so that when the first dispenser applies liquid to the first surface of a flat article on the rotatable support, a first meniscus of liquid is formed between a portion of the first transmitter and the first surface of the flat article; and a second transducer assembly comprising a second transducer for generating acoustic energy and a second transmitter acoustically coupled to the second transducer, the second transducer assembly positioned so that when the second dispenser applies liquid to the second surface of the flat article on the rotatable support, a second meniscus of liquid is formed between a portion of the second transmitter and the second surface of the flat article.

Description

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is schematic of an acoustic energy cleaning system according to one embodiment of the present invention.

FIG. 2 is a perspective view of one structural embodiment of the acoustic energy cleaning system of FIG. 1.

FIG. 3 is a cross-sectional side view of the acoustic energy cleaning system of FIG. 2.

FIG. 4 is a transducer assembly according to one embodiment of the present invention that is utilized in the acoustic energy cleaning system of FIG. 2 as the bottom-side transducer assembly.

FIG. 5 is a cross-sectional view of the transducer assembly of FIG. 4 along cross-section cut A-A of FIG. 4.

FIG. 6 is an exploded view of the transducer assembly of FIG. 4.

FIG. 7 is a schematic of the transducer assembly of FIG. 4 positioned adjacent a bottom surface of a semiconductor wafer according to an embodiment of the present invention wherein the transducer assembly of FIG. 4 is shown in cross-section.

FIG. 8 is a schematic representation of one arrangement of the topside transducer assembly relative to the bottom-side transducer assembly for the acoustic energy cleaning system of FIG. 2.

FIG. 9 is a cross-sectional view of the schematic representation of the transducer assembly arrangement of FIG. 8 along the cross-section cut B-B of FIG.8.

FIG. 10 is a schematic representation of an alternative arrangement of the topside transducer assembly relative to the bottom-side transducer assembly for the acoustic energy cleaning system of FIG. 2.

FIG. 11 is a cross-sectional view of the schematic representation of the alternative transducer assembly arrangement of FIG. 10 along the cross-section cut C-C of FIG.8.

FIG. 12 is schematic of an acoustic energy cleaning system utilizing a reflective member according to one embodiment of the present invention.

FIG. 13 is schematic of an acoustic energy cleaning system utilizing a reflective member according to an alternative embodiment of the present invention.

FIG. 14 shows five alternative embodiments of a transducer assembly that can also act as a reflective member for use in the acoustic energy cleaning system of FIG. 12.

Claims

1. A system for processing flat articles comprising: a rotatable support for supporting a flat article;a first dispenser for applying liquid to a first surface of a flat article on the rotatable support;a second dispenser for applying liquid to a second surface of a flat article on the rotatable support;a first transducer assembly comprising a first transducer for generating acoustic energy and a first transmitter acoustically coupled to the first transducer, the first transducer assembly positioned so that when the first dispenser applies liquid to the first surface of a flat article on the rotatable support, a first meniscus of liquid is formed between a portion of the first transmitter and the first surface of the flat article; anda second transducer assembly comprising a second transducer for generating acoustic energy and a second transmitter acoustically coupled to the second transducer, the second transducer assembly positioned so that when the second dispenser applies liquid to the second surface of the flat article on the rotatable support, a second meniscus of liquid is formed between a portion of the second transmitter and the second surface of the flat article.

2. The system of claim 1 wherein the rotatable support supports and rotates the flat article in a substantially horizontal orientation, the first surface of the article being a top surface and the second surface of the article being a bottom surface.

3. The system of claim 1 further comprising an actuator operably connected to the second transducer assembly for moving the second transducer assembly between a processing position and a retracted position.

4. The system of claim 3 further: wherein the rotatable support supports and rotates the flat article in a substantially horizontal orientation, the first surface of the article being a top surface and the second surface of the article being a bottom surface; andwherein the processing position is a raised position and the retracted position is a lowered position.

5. The system of claim 1 further comprising: an actuator operably connected to the second transducer assembly for moving the second transducer assembly between a processing position and a retracted position;a sensor for indicating the position of the second transducer assembly;a controller operably coupled to the sensor and the actuator; andthe controller programmed to stop movement of the second transducer assembly upon receiving a signal from the sensor indicating that the second transducer assembly is in the processing position.

6. The system of claim 1 further comprising: an actuator operably connected to the second transducer assembly for moving the second transducer assembly between a processing position and a retracted position; andmeans for physically prohibiting the second transducer assembly from moving beyond the processing position when moving from the retracted position to the processing position.

7. The system of claim 1 further: wherein the portion of the first transmitter comprises a first elongate edge that extends substantially parallel to the first surface of an article on the rotatable support; andwherein the portion of the second transmitter comprises a second elongate edge that extends substantially parallel to the second surface of an article on the rotatable support.

8. The system of claim 1 further comprising a source of cleaning liquid operably connected to the first dispenser and the second dispenser.

9. The system of claim 1 further comprising a base for supporting the second transducer assembly, the second dispenser being a plurality of nozzles located in the base and adapted to apply liquid to the second surface of a flat article on the rotatable support.

10. The system of claim 1 wherein the second transducer assembly further comprises a housing connected to the second transmitter so as to form a substantially enclosed space in which the second transducer is located, the housing comprising one or more openings for flowing a gas into and/or out of the space.

11. The system of claim 10 further comprising a source of gas operably coupled to the one or more openings.

12. The system of claim 10 wherein the second transmitter and the housing are encapsulated in an inert non-reactive plastic.

13. The system of claim 1 wherein the second transmitter has a convex outer surface having an elongate edge, the second transducer assembly positioned so that when the second dispenser applies liquid to the second surface of the flat article on the rotatable support, the second meniscus of liquid is formed between the elongated edge of the outer convex surface of the second transmitter and the second surface of the flat article.

14. The system of claim 13 further comprising a dam surrounding at least a portion of a perimeter of the second transmitter so as to form a liquid retaining channel, the elongate edge of the second transmitter protruding beyond a top of the dam.

15. The system of claim 1 further comprising: a dam surrounding at least a portion of a perimeter of the second transmitter so as to form a liquid retaining channel; andthe second transmitter having a convex outer surface having an apex, the apex of the second transmitter protruding beyond a top of the dam.

16. The system of claim 1 further comprising a dam surrounding at least a portion of a perimeter of the second transmitter so as to form a liquid retaining channel between the second transmitter and the dam.

17. The system of claim 1 wherein the portion of the first transmitter and the portion of the second transmitter oppose one other.

18. The system of claim 1 wherein the portion of the first transmitter and the portion of the second transmitter do not oppose one other.

19. The system of claim 1 further comprising: a controller operably coupled to the first transducer assembly and to the second transducer assembly;the controller programmed to operate the first transducer assembly and the second transducer assembly consecutively.

20. The system of claim 1 further comprising: a controller operably coupled to the first transducer assembly and to the second transducer assembly;the controller programmed to operate the first transducer assembly and the second transducer assembly contemporaneously.

21. The system of claim 1 further comprising: a controller operably coupled to the first transducer assembly and to the second transducer assembly;the controller programmed to operate the first transducer assembly and the second transducer assembly in an alternating manner.

22. The system of claim 1 wherein the second transmitter is a par-cylindrical plate having a concave inner surface and a convex outer surface.

23. The system of claim 22 wherein the second transducer has a convex surface having a curvature that corresponds to a curvature of the concave inner surface of the second transmitter.

24. A system for cleaning flat articles comprising: a rotatable support for supporting a flat article;a first transducer assembly comprising a first transducer and a first transmitter acoustically coupled to the first transducer, the first transducer assembly positioned so that a first small gap exists between a portion of the first transmitter and a first surface of a flat article on the rotatable support, a first meniscus of liquid being formed between the portion of the first transmitter and the first surface of the flat article when liquid is applied to the first surface; anda second transducer assembly comprising a second transducer and a second transmitter acoustically coupled to the second transducer, the second transducer assembly positioned so that a second small gap exists between a portion of the second transmitter and a second surface of the flat article on the rotatable support, a second meniscus of liquid being formed between the portion of the second transmitter and the second surface when liquid is applied to the second surface.

25. A system for processing flat articles comprising: a rotatable support for supporting and rotating a flat article in a substantially horizontal orientation;a transducer assembly comprising a transducer for generating acoustic energy, a transmitter acoustically coupled to the first transducer and a dam surrounding at least a portion of a perimeter of the transmitter so as to form a liquid retaining channel between the transmitter and the dam; andthe transducer assembly positioned so that a portion of the transmitter is adjacent a bottom surface of a flat article on the rotatable support so that when liquid is applied to the bottom surface of the flat article, a meniscus of liquid is formed between the portion of the transmitter and the bottom surface of the flat article.