Substrate support with multiple embedded electrodes

• US 10,510,575 B2
• Filed: 09/20/2017
• Issued: 12/17/2019
• Est. Priority Date: 09/20/2017
• Status: Active Grant

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Applied Materials Incorporated
• Inventors: Kraus, Philip Allan, Chua, Thai Cheng, Cho, Jaeyong
• Primary Examiner(s): Bennett, Charlee J C
• Application Number:
  US15/710,753
• Publication Number:
  US 20190088520A1
• Time in Patent Office: 818 Days
• Field of Search: 118715-733, 1563451-34555
• CPC Class Codes: H01J 37/00 Discharge tubes with provision for introducing objects or material to be exposed to the discharge, e.g. for the purpose of examination or processing thereof H01J33/00, H01J40/00, H01J41/00, H01J47/00, H01J49/00 take precedence
• CPC Class Codes: H01J 37/32568 Relative arrangement or disposition of electrodes; moving means
• CPC Class Codes: H01J 37/32706 Polarising the substrate
• CPC Class Codes: H01J 37/32715 Workpiece holder
• CPC Class Codes: H01L 21/0262 Reduction or decomposition of gaseous compounds, e.g. CVD
• CPC Class Codes: H01L 21/2236 from or into a plasma phase
• CPC Class Codes: H01L 21/3065 Plasma etching; Reactive-ion etching
• CPC Class Codes: H01L 21/67069 for drying etching
• CPC Class Codes: H01L 21/67109 mainly by convection
• CPC Class Codes: H01L 21/6833 Details of electrostatic chucks
• CPC Class Codes: H01L 21/68742 characterised by a lifting arrangement, e.g. lift pins

Abstract

A method and apparatus for biasing regions of a substrate in a plasma assisted processing chamber are provided. Biasing of the substrate, or regions thereof, increases the potential difference between the substrate and a plasma formed in the processing chamber thereby accelerating ions from the plasma towards the active surfaces of the substrate regions. A plurality of bias electrodes herein are spatially arranged across the substrate support in a pattern that is advantageous for managing uniformity of processing results across the substrate.

Claims

1. A substrate support assembly, comprising:

a plurality of first electrodes within a substrate support, wherein

each electrode of the plurality of first electrodes is electrically isolated from every other electrode of the plurality of first electrodes,

each electrode of the plurality of first electrodes is configured to provide a pulsed DC power to a region of a substrate through capacitive coupling therewith,

each electrode of the plurality of first electrodes is independently electrically coupled to a respective switching pair of a pulsed DC biasing switching system,

each switching pair comprises a distinct first switch and a distinct second switch,

each of the switching pairs is configured to operate independently of the other switching pairs, and

the first switches are electrically coupled to a first DC voltage source and the second switches are electrically coupled to a second DC voltage source; and

a second electrode disposed within the substrate support, and electrically isolated from the plurality of first electrodes, for electrically clamping the substrate to the substrate support.

2. The substrate support assembly of claim 1, wherein at least a portion of each electrode of the plurality of first electrodes is coplanar with the second electrode.

3. The substrate support assembly of claim 1, wherein at least a portion of one or more electrodes of the plurality of first electrodes is closer to a substrate support surface of the substrate support than the second electrode.

4. The substrate support assembly of claim 1, further comprising a dielectric layer disposed between the plurality of first electrodes and a substrate support surface of the substrate support, wherein the dielectric layer has a thickness of between about 5 μ

m and about 300 μ

m.

5. The substrate support assembly of claim 1, wherein the second electrode comprises a unitary conductive body.

6. The substrate support assembly of claim 1, wherein each switch of the switching pairs is a solid state switch configured to switch at a frequency up to about 100 kHz.

7. The substrate support assembly of claim 1, further comprising a cooling base thermally coupled to the substrate support.

8. A processing chamber, comprising:

one or more sidewalls and a bottom defining a processing volume; and

a substrate support, comprising;

a plurality of first electrodes within the substrate support, each electrode of the plurality of first electrodes electrically isolated from every other electrode of the plurality of first electrodes, wherein

each electrode of the plurality of first electrodes is configured to provide a pulsed DC bias to a region of a substrate through capacitive coupling therewith,

each electrode of the plurality of first electrodes is independently electrically coupled to a respective switching pair of a pulsed DC biasing switching system,

each switching pair comprises a distinct first switch and a distinct second switch,

each of the switching pairs is configured to operate independently of the other switching pairs, and

the first switches are electrically coupled to a first DC voltage source and the second switches are electrically coupled to a second DC voltage source; and

a second electrode disposed within the substrate support, and electrically isolated from the plurality of first electrodes, for electrically clamping the substrate to the substrate support.

9. The processing chamber of claim 8, wherein at least a portion of each electrode of the plurality of first electrodes is coplanar with the second electrode.

10. The processing chamber of claim 8, wherein at least a portion of one or more electrodes of the plurality of first electrodes is closer to a substrate support surface of the substrate support than the second electrode.

11. The processing chamber of claim 8, wherein a layer of dielectric material disposed between the plurality of first electrodes and a substrate support surface of the substrate support is between about 5 μ

m and about 300 μ

m thick.

12. The processing chamber of claim 8, wherein the second electrode comprises a unitary conductive material part electrically isolated from the plurality of first electrodes.

13. A substrate processing system, comprising:

a substrate support formed of a dielectric material;

an ESC electrode disposed in the substrate support;

a plurality of spatially arranged bias electrodes disposed in the substrate support, wherein each of the spatially arranged bias electrodes and the ESC electrode are electrically isolated from each other by the dielectric material of the substrate support disposed therebetween; and

a DC power supply switching system comprising a plurality of first solid state switches coupled to a first DC power source and a plurality of second solid state switches coupled to a second DC power source, wherein each bias electrode is electrically coupled to one of the plurality of first solid state switches and to one of the plurality of second solid state switches.

14. The substrate processing system of claim 13, wherein the ESC electrode is formed of a unitary conductive body.

15. The substrate processing system of claim 14, wherein a layer of dielectric material disposed between the plurality of bias electrodes and a substrate supporting surface of the substrate support has a breakdown voltage of between about 20 V/μ

m and about 200 V/μ

m.

16. The substrate processing system of claim 15, wherein the layer of dielectric material disposed between the plurality of bias electrodes and the substrate supporting surface of the substrate support is between about 5 μ

m and about 300 μ

m thick.

17. The substrate processing system of claim 16, wherein one of more of the plurality of first solid state switches is capable of converting a high voltage (HV) DC power to a cyclic DC voltage having a frequency between about 10 Hz and about 100 kHZ.