Method and apparatus for removing material from a substrate surface

• US 20060037700A1
• Filed: 08/15/2005
• Published: 02/23/2006
• Est. Priority Date: 08/18/2004
• Status: Abandoned Application

• Current Assignee: Nanofilm Technologies International Pte., Ltd.
• Original Assignee: Nanofilm Technologies International Pte., Ltd.
• Inventors: Shi, Xu, Cheah, Li Kang
• Application Number:
  US11/203,895
• Publication Number:
  US 20060037700A1
• Time in Patent Office: Days
• US Class Current: 156/345.430
• CPC Class Codes: B29C 33/72 Cleaning extruder parts B29C48/27; in general B08B7/00
• CPC Class Codes: H01J 2237/0206 Extinguishing, preventing or controlling unwanted discharges
• CPC Class Codes: H01J 2237/335 Cleaning
• CPC Class Codes: H01J 37/32027 DC powered
• CPC Class Codes: H01L 21/02068 during, before or after processing of conductive layers, e.g. polysilicon or amorphous silicon layers
• CPC Class Codes: H01L 21/31138 by dry-etching
• CPC Class Codes: H01L 2224/85009 Pre-treatment of the connector or the bonding area
• CPC Class Codes: H01L 2224/85013 Plasma cleaning
• CPC Class Codes: H05K 3/26 Cleaning or polishing of the conductive pattern

Abstract

Methods and apparatus for removing material from a substrate, such as an IC component, are disclosed. The methods include creating a plasma in an evacuatable chamber, by providing a power source to an electrode in the chamber, and contacting the substrate surface with at least one of ions, atoms and free radicals of the plasma. The power source, preferably DC, is supplied to the electrode as a variable, and preferably a pulsed voltage to prevent arcing.

Claims

1. A method of removing material from a substrate surface comprising the steps of:

providing a plasma using a power source; and

contacting the substrate surface with one or more of ions, atoms or free radicals of the plasma,

wherein the power source is supplied as a variable voltage.

3. The method of claim 1 wherein the variable voltage is a pulsed voltage.

4. The method of claim 1 wherein the voltage is pulsed once per consecutive 3-30 kHz periods.

5. The method of claim 1 wherein the variable voltage is pulsed from 0V to a voltage between −

300V and −

1000V.

6. The method of claim 1 wherein the variable voltage is pulsed from 0V to a voltage between −

380V and −

600V.

7. The method of claim 1 wherein the voltage is applied in a 3 to 20 μ

s pulse.

8. The method of claim 1 comprising two opposed electrodes, wherein the power source is supplied to one of the electrodes and the other electrode is floating, and wherein the substrate is on the floating electrode.

9. The method of claim 1 comprising two opposed electrodes, wherein the power source is supplied to one of the electrodes and the other electrode is grounded, and wherein the substrate is on the grounded electrode.

10. The method of claim 1 comprising two opposed electrodes, wherein the power source is supplied to one of the electrodes, and the other electrode is floating, wherein the substrate is on said one of the electrodes.

11. The method of claim 1 comprising two opposed electrodes, wherein the power source is supplied to one of the electrodes, and the other electrode is grounded, wherein the substrate is on said one of the electrodes.

12. The method of claim 1 comprising two opposed electrodes, wherein the power source is supplied to both of the electrodes, and the other electrode is floating, wherein the substrate is on the one of the electrodes.

13. The method of claim 1 wherein the plasma is provided in an O₂ environment.

14. The method of claim 1 wherein the plasma is provided in an O₂/CF₄ environment.

15. The method of claim 1 wherein the plasma is provided in a chamber evacuated to about 80 to 1500 mTorr.

16. The method of claim 8 comprising two said substrates located on respective electrodes.

17. The method of claim 8 comprising a plurality of spaced electrodes, at least some of which respectively support a respective one of a plurality of said substrates.

18. The method of claim 8 wherein at least one of the electrodes supports at least two said substrates on one or both of its opposing sides.

19. The method of claim 1 wherein the substrate is one of an IC, IC component, IC mould, die, wafer, ball grid array, IC package, leadframe, PCB, microvia, disk holder, reader arm, or hard disk.

20. The method of claim 1 wherein the material is one of an organic substance, organic contaminant, solvent residue or epoxy resin.

2. A method of removing material from a substrate surface comprising the steps of:

placing the substrate in an evacuatable chamber having an electrode therein;

providing a variable voltage to the electrode to provide a plasma in the chamber between the electrode and the substrate; and

contacting the substrate surface with one or more of ions, atoms or free radicals of the plasma to remove at least a portion of the material on the surface.

21. Apparatus for removing material from a substrate surface comprising:

a vacuum chamber;

an electrode in the vacuum chamber; and

a power source for providing a variable voltage to the electrode, such that a plasma is formable within the chamber and one or more of ions, atoms or free radicals of the plasma contact the substrate surface,

wherein the power source is supplied as a variable voltage.

22. The apparatus of claim 21 wherein the variable voltage is configured to be provided as a pulsed voltage.

23. The apparatus of claim 21 comprising two opposed electrodes, wherein the power source is supplied to one of the electrodes and the other electrode is floating, and wherein the substrate is on the floating electrode.

24. The apparatus of claim 21 comprising two opposed electrodes, wherein the power source is supplied to one of the electrodes and the other electrode is grounded, and wherein the substrate is on the grounded electrode.

25. The apparatus of claim 21 comprising two opposed electrodes, wherein the power source is supplied to one of the electrodes, and the other electrode is floating, wherein the substrate is on said one of the electrodes.

26. The apparatus of claim 21 comprising two opposed electrodes, wherein the power source is supplied to one of the electrodes, and the other electrode is grounded, wherein the substrate is on said one of the electrodes.

27. The apparatus of claim 21 comprising two opposed electrodes, wherein the power source is supplied to both of the electrodes, and the other electrode is floating, wherein the substrate is on the one of the electrodes.

28. The apparatus of claim 21 comprising a plurality of spaced electrodes, at least some of which respectively support a respective one of a plurality of said substrates.

29. The apparatus of claim 21 wherein the chamber comprises an opening adapted for hermetic abutment with a surface of a conveyor, the substrate being positioned on the conveyor.

30. The apparatus of claim 21 wherein the substrate is one of an IC, IC component, IC mould, die, wafer, ball grid array, IC package, leadframe, PCB, microvia, disk holder, reader arm, or hard disk.

31. The apparatus of claim 21 wherein the material is one of an organic substance, organic contaminant, solvent residue or epoxy resin.