Spin chuck for thin wafer cleaning

• US 9,153,462 B2
• Filed: 12/09/2010
• Issued: 10/06/2015
• Est. Priority Date: 12/09/2010
• Status: Active Grant

• Current Assignee: Taiwan Semiconductor Manufacturing Company Limited
• Original Assignee: Taiwan Semiconductor Manufacturing Company Limited
• Inventors: Lin, Yu-Liang, Wu, Weng-Jin, Lin, Jing-Cheng, Chiou, Wen-Chih
• Primary Examiner(s): KO, JASON Y
• Application Number:
  US12/964,097
• Publication Number:
  US 20120145204A1
• Time in Patent Office: 1,762 Days
• Field of Search: None
• US Class Current: 1/1
• CPC Class Codes: H01L 21/67051 using mainly spraying means, e.g. nozzles
• CPC Class Codes: H01L 21/68728 characterised by a plurality of separate clamping members, e.g. clamping fingers

Abstract

A device and system for thin wafer cleaning is disclosed. A preferred embodiment comprises a spin chuck having at least three holding clamps. A thin wafer with a wafer frame is mounted on the spin chuck through a tape layer. When the holding clamps are unlocked, there is no interference with the removal and placement of the wafer frame. On the other hand, when the holding clamps are locked, the holding clamps are brought into contact with the outer edge of the wafer frame so as to prevent the wafer frame from moving laterally. Furthermore, the shape of the holding clamps in a locked position is capable of preventing the wafer frame from moving vertically.

Claims

1. A device for cleaning a thin wafer comprising:

a spin chuck comprising;

a circular shaped plate having at least three extensions spaced along the edge of the circular shaped plate, wherein top surfaces of the at least three extensions are level with a top surface of the circular shaped plate, and bottom surfaces of the at least three extensions are level with a bottom surface of the circular shaped plate;

a tape layer on the circular shaped plate and a wafer frame on the tape layer;

at least three holding clamps mounted on the extensions, wherein each holding clamp can be unlocked by placing a non-vertical side of the holding clamp at a first position and can be locked by rotating the holding clamp and placing the non-vertical side of the holding clamp at a second position, wherein the second position is rotated by 180 degrees from the first position, and wherein a distance from an axis of rotation of the holding clamp to a center of the circular shaped plate is greater than a distance from the second position to the center of the circular shaped plate, and wherein the tape layer and the holding clamp are separated by the wafer frame and the axis of rotation is outside the wafer frame; and

a rotational drive shaft connected the circular shaped plate.

2. The device of claim 1, wherein the extensions have a half-oval shape.

3. The device of claim 2, wherein the rotational drive shaft is driven by a motor.

4. The device of claim 3, wherein the speed of the motor is between 500 and 1000 rpm.

5. The device of claim 1, wherein the holding clamp further includes an upper portion and a bottom portion, and wherein the upper portion and the bottom portion form a half-cup shaped holding clamp, and wherein the half-cup shaped holding clamp and a wafer are separated by a wafer frame when the half-cup shaped holding clamp is locked at the second position.

6. The device of claim 5, wherein the lower portion extends substantially orthogonally to the circular shaped plate and the upper portion projects outward from a center of the circular shaped plate when the holding clamp is in the first position and the upper portion projects inward toward the center of the circular shaped plate when the holding clamp is in the second position.

7. The device of claim 1, wherein the circular shaped plate has a diameter of approximately 400 mm.

8. The device of claim 1, further comprising one additional extension and one additional holding clamp wherein all extensions of the circular shaped plate are spaced along the edge of the circular shaped plate and each extension has a holding clamp.

9. A system for cleaning a thin wafer comprising:

a spin chuck comprising;

a circular shaped plate having at least three extensions spaced along the edge of the circular shaped plate and configured to receive thereon a tape layer having a first diameter, wherein top surfaces of the at least three extensions are level with a top surface of the circular shaped plate, and bottom surfaces of the at least three extensions are level with a bottom surface of the circular shaped plate;

at least three holding clamps each having an upper portion and a bottom portion mounted on the extensions, wherein each holding clamp can be unlocked in a first position and can be locked by rotating the holding clamp from the first position to a second position, wherein the second position is rotated by 180 degrees from the first position; and

a rotational drive shaft connected the circular shaped plate; and

a wafer frame mounted on the spin chuck and configured to secure the tape layer, wherein the holding clamp and the tape layer are separated by the wafer frame when the holding clamp is at the second position, and a height of the bottom portion is equal to a height of the wafer frame.

10. The system of claim 9, wherein the wafer frame is ring-shaped with an outer edge having an outer diameter and an inner edge having an inside diameter.

11. The system of claim 10, wherein the outer diameter of the wafer frame is larger than the diameter of the tape layer and the inside diameter of the wafer frame is smaller than the diameter of the tape layer.

12. The system of claim 9, wherein when the holding clamps are locked, the upper portion of the holding clamps prevent the wafer frame from moving vertically.

13. The system of claim 9, wherein when the holding clamps are locked, the bottom portion of the holding clamps is brought into contact with the outer edge of the wafer frame so as to prevent the wafer frame from moving laterally.

14. The system of claim 9, further comprising a tape layer region between the inner edge of the wafer frame and a thin wafer mounted on the tape layer, wherein the tape layer region is non-adhesive.

15. The system of claim 9, further comprising one additional extension and one additional holding wherein all extensions of the circular shaped plate are spaced along the edge of the circular shaped plate and each extension has a holding clamp.

16. A system for thin wafer cleaning comprising:

a spin chuck comprising;

a circular shaped plate having at least three extensions spaced along the edge of the circular shaped plate and configured to receive thereon a tape layer, wherein top surfaces of the at least three extensions are level with a top surface of the circular shaped plate, and bottom surfaces of the at least three extensions are level with a bottom surface of the circular shaped plate;

at least three holding clamps each having an upper portion and a bottom portion mounted on the extensions, wherein each holding clamp can be unlocked in a first position and can be locked by rotating the holding clamp from the first position to a second position, wherein the second position is rotated by 180 degrees from the first position; and

a rotational drive shaft connected the circular shaped plate;

a wafer frame mounted on the spin chuck and configured to secure the tape layer, wherein the holding clamp and the tape layer are separated by the wafer frame when the holding clamp is at the second position, and a height of the bottom portion is greater than a height of the tape layer;

a cup having an inner wall and an outer wall;

at least three spray nozzles attached to the inner wall of the cup and at least three pipes attached to the outer wall of the cup;

a chemical solvent nozzle placed inside the cup and above the spin chuck; and

a waste chemical absorber.

17. The system of claim 16, wherein the chemical solvent nozzle includes a first pipe supplying pressurized chemical solvents and a second pipe supplying nitrogen.

18. The system of claim 16, wherein the chemical solvent nozzle further includes a channel in which the pressurized chemical solvents and nitrogen are mixed.

19. The system of claim 16, wherein the waste chemical absorber is placed on the tape layer.

20. The system of claim 16, wherein the spray nozzles supply air, de-ionized water, surfactant and any combination of thereof.