Systems and methods for correcting non-uniformities in plasma processing of substrates

Patent metadata

Field	Value
Publication number	US-10872748-B2
Application number	US-201916506456-A
Country	US
Kind code	B2
Filing date	Jul 9, 2019
Priority date	Sep 16, 2011
Publication date	Dec 22, 2020
Grant date	Dec 22, 2020

Abstract

An electrostatic chuck includes an embedded electrode receiving a first voltage to electrostatically attract a semiconductor substrate to the electrostatic chuck. A plurality of current loops are disposed in at least one of the electrostatic chuck and an edge ring surrounding the electrostatic chuck. The current loops are laterally spaced apart. Each current loop is a wire formed into a loop. One or more DC power sources are electrically connected to the current loops. A controller supplies the first voltage to the embedded electrode, supplies a DC current to the current loops from the power sources, and controls the power sources. Each current loop is independently operable and generates a localized DC magnetic field proximate to the semiconductor substrate on receiving the DC current during plasma processing of the semiconductor substrate to adjust the plasma processing of the semiconductor substrate. The localized DC magnetic field does not generate plasma.

First claim

What is claimed is:

1. A system comprising:
an electrostatic chuck including an embedded electrode receiving a first voltage to electrostatically attract a semiconductor substrate to the electrostatic chuck; and
a plurality of current loops disposed in at least one of the electrostatic chuck and an edge ring surrounding the electrostatic chuck, wherein the plurality of current loops are laterally spaced apart, and wherein each of the plurality of current loops is a wire formed into a loop;
one or more DC power sources electrically connected to the plurality of current loops; and
a controller configured to:
supply the first voltage to the embedded electrode;
supply a DC current to the plurality of current loops from the one or more DC power sources; and
control the one or more DC power sources such that each of the plurality of current loops is independently operable and generates a localized DC magnetic field proximate to the semiconductor substrate on receiving the DC current during plasma processing of the semiconductor substrate to adjust the plasma processing of the semiconductor substrate,
wherein the localized DC magnetic field generated by the plurality of current loops does not generate plasma.

2. The system of claim 1 wherein the localized DC magnetic field generated by the plurality of current loops adjusts an etch rate during the plasma processing of the semiconductor substrate.

3. The system of claim 1 wherein the controller is configured to supply the DC current to one or more of the plurality of current loops in response to detecting an etch rate non-uniformity during the plasma processing of the semiconductor substrate.

4. The system of claim 1 wherein the controller is configured to supply the DC current to one or more of the plurality of current loops initially in a first direction and subsequently in a second direction that is opposite of the first direction.

5. The system of claim 1 wherein the controller is configured to supply the DC current to the plurality of current loops in the same direction.

6. The system of claim 1 wherein the controller is configured to supply the DC current to the plurality of current loops in different directions.

7. The system of claim 1 wherein the controller is configured to supply the DC current to the plurality of current loops at the same time.

8. The system of claim 1 wherein the controller is configured to supply the DC current to the plurality of current loops at different times.

9. The system of claim 1 wherein the controller is configured to supply the same amount of the DC current to the plurality of current loops.

10. The system of claim 1 wherein the controller is configured to supply different amounts of the DC current to the plurality of current loops.

11. The system of claim 1 wherein the controller is configured to supply the DC current to the plurality of current loops using a multiplexing scheme.

12. The system of claim 1 wherein the plurality of current loops are embedded in a baseplate of the electrostatic chuck.

13. The system of claim 1 wherein the plurality of current loops are embedded in a ceramic plate of the electrostatic chuck.

14. The system of claim 1 wherein the plurality of current loops are electrically isolated from the embedded electrode.

15. The system of claim 1 wherein the plurality of current loops are electrically insulated.

16. The system of claim 1 wherein the plurality of current loops lie in a plane parallel to the semiconductor substrate.

17. The system of claim 1 wherein the plurality of current loops in the electrostatic chuck and in the edge ring are not planar with respect to each other.

18. The system of claim 1 wherein the plurality of current loops in the electrostatic chuck and in the edge ring are not planar with respect to the semiconductor substrate.

19. The system of claim 1 wherein the plurality of current loops extend less than halfway around the electrostatic chuck or the edge ring.

20. The system of claim 1 wherein a periphery of each current loop of the plurality of current loops is laterally offset from a periphery of an adjacent current loop of the plurality of current loops.

21. The system of claim 1 wherein the plurality of current loops have the same size and shape.

22. The system of claim 1 wherein the plurality of current loops have different sizes and shapes.

23. The system of claim 1 wherein at least one of the plurality of current loops has a circular, semi-circular, oval, semi-oval, square, rectangular, trapezoidal, triangular, or polygonal shape.

24. The system of claim 1 wherein at least one of the plurality of current loops comprises a single turn.

25. The system of claim 1 wherein at least one of the plurality of current loops comprises a plurality of turns.

Assignees

• Lam Res Corp

Inventors

• Singh Harmeet
• Gaff Keith
• Richardson Brett
• Lee Sung

Classifications

• H10P72/0421

  for drying etching · CPC title

• H10P50/283

  by chemical means · CPC title

• H01F7/20

  without armatures (cores H01F3/00; coils H01F5/00 {; shaping metal by applying magnetic forces B21D26/14; electromagnets specially adapted for NMR applications G01R33/381}) · CPC title

• C23C16/4586

  Elements in the interior of the support, e.g. electrodes, heating or cooling devices · CPC title

• H02N13/00

  Clutches or holding devices using electrostatic attraction, e.g. using Johnson-Rahbek effect · CPC title