Ceramic Electrostatic Chuck Including Embedded Faraday Cage for RF Delivery and Associated Methods for Operation, Monitoring, and Control

Patent metadata

Field	Value
Publication number	US-2018130690-A1
Application number	US-201715690203-A
Country	US
Kind code	A1
Filing date	Aug 29, 2017
Priority date	Nov 8, 2016
Publication date	May 10, 2018
Grant date	—

Abstract

A ceramic assembly is attached to a lower support structure having a bowl shape. The ceramic assembly has a top surface configured to support a substrate. At least one clamp electrode is positioned within an upper region of the ceramic assembly. A primary radiofrequency (RF) power delivery electrode is positioned within the ceramic assembly at a location vertically below the at least one clamp electrode such that a region of the ceramic assembly between the primary RF power delivery electrode and the at least one clamp electrode is substantially free of other electrically conductive material. A plurality of RF power delivery connection modules is distributed in a substantially uniform manner about a perimeter of the ceramic assembly. Each of the RF power delivery connection modules is configured to form an electrical connection from the lower support structure to the primary RF power delivery electrode at its respective location.

First claim

What is claimed is:

1 . An electrostatic chuck, comprising:
a ceramic assembly having a top surface including an area configured to support a substrate; at least one clamp electrode positioned within the ceramic assembly in an orientation substantially parallel to the top surface of the ceramic assembly and at an upper location within the ceramic assembly such that a region of the ceramic assembly between the at least one clamp electrode and the top surface of the ceramic assembly is substantially free of other electrically conductive material; a primary radiofrequency (RF) power delivery electrode positioned within the ceramic assembly in an orientation substantially parallel to the top surface of the ceramic assembly and at a location vertically below the at least one clamp electrode such that a region of the ceramic assembly between primary RF power delivery electrode and the at least one clamp electrode is substantially free of other electrically conductive material, and wherein the primary RF power delivery electrode is configured to extend horizontally through the ceramic assembly to at least span an area underlying the area of the top surface of the ceramic assembly that is configured to support the substrate; a lower support structure formed of an electrically conductive material, the lower support structure having a bowl shape formed by a bottom plate member and an annular-shaped wall member extending upward from the bottom plate member, the ceramic assembly secured to the lower support structure such that an outer peripheral region of a bottom surface of the ceramic assembly is supported by a top surface of the annular-shaped wall member of the lower support structure with an interior region of the lower support structure exposed to a portion the bottom surface of the ceramic assembly; and a plurality of RF power delivery connection modules distributed in a substantially uniform manner about a perimeter of the ceramic assembly, each of the plurality of RF power delivery connection modules configured to form an electrical connection from the lower support structure to the primary RF power delivery electrode at its respective location so as to form an RF power transmission path from the lower support structure to the primary RF power delivery electrode at its respective location, wherein the lower support structure, the plurality of RF power delivery connection modules, and the primary RF power delivery electrode together form a Faraday cage to direct RF power transmission around an interior region of the electrostatic chuck.

2 . The electrostatic chuck as recited in claim 1 , wherein each of the plurality of RF power delivery connection modules includes a first electrical connection extending between the lower support structure and an exposed embedded conductive segment within the ceramic assembly, wherein a portion of the exposed embedded conductive segment is exposed at a bottom of the ceramic assembly, and wherein each of the plurality of RF power delivery connection modules includes a second electrical connection extending between the exposed embedded conductive segment through the ceramic assembly to the primary RF power delivery electrode.

3 . The electrostatic chuck as recited in claim 2 , wherein the first electrical connection includes an electrically conductive pin in compression against the exposed portion of the exposed embedded conductive segment, wherein the electrically conductive pin is electrically connected to the lower support structure to enable transmission of RF signals from the lower support structure to the electrically conductive pin.

4 . The electrostatic chuck as recited in claim 3 , wherein the electrically conductive pin is configured to transmit up to 30 amperes of electrical current.

5 . The electrostatic chuck as recited in claim 2 , wherein the second electrical connection includes one or more interior embedded conductive segments within the ceramic assembly, wherein each of the one or more interior embedded conductive segments is oriented substantially parallel to the primary RF power delivery electrode, and wherein the second electrical connection includes one or more vertical conductive structures positioned to electrically connect the one or more interior embedded conductive segments to each other and to the exposed embedded conductive segment and to the primary RF power delivery electrode.

6 . The electrostatic chuck as recited in claim 5 , wherein at least one of the vertical conductive structures extends through the ceramic assembly between the exposed embedded conductive segment and a lowest one of the interior embedded conductive segments, and wherein at least one of the vertical conductive structures extends through the ceramic assembly between a highest one of the interior embedded conductive segments and the primary RF power delivery electrode, and wherein at least one of the vertical conductive structures extends through the ceramic assembly between each vertically neighboring set of two of the interior embedded conductive segments when present.

7 . The electrostatic chuck as recited in claim 5 , wherein at least four of the vertical conductive structures extends through the ceramic assembly between the exposed embedded conductive segment and a lowest one of the interior embedded conductive segments, and wherein at least four of the vertical conductive structures extends through the ceramic assembly between a highest one of the interior embedded conductive segments and the primary RF power delivery electrode, and wherein at least four of the vertical conductive structures extends through the ceramic assembly between each vertically neighboring set of two of the interior embedded conductive segments when present.

8 . The electrostatic chuck as recited in claim 2 , wherein the plurality of RF power delivery connection modules includes eight RF power delivery connection modules positioned near a periphery of the ceramic assembly, with each of the eight RF power delivery connection modules separated from each adjacent one of the eight RF power delivery connection modules by an angle of about 45 degrees as measured about a centerline of the ceramic assembly extending perpendicular to the top surface of the ceramic assembly.

9 . The electrostatic chuck as recited in claim 1 , wherein the primary RF power delivery electrode is formed as a disc-shaped member.

10 . The electrostatic chuck as recited in claim 1 , wherein the primary RF power delivery electrode is sectioned in a radially symmetric manner about a centerline of the ceramic assembly extending perpendicular to the top surface of the ceramic assembly, with each section of the primary RF power delivery electrode separated from adjacent sections of the primary RF power delivery electrode, and with each section of the primary RF power delivery electrode connected to receive RF power from a respective one of the plurality of RF power delivery connection modules.

11 . The electrostatic chuck as recited in claim 1 , further comprising:
a perimeter RF power delivery electrode formed within the ceramic assembly at a vertical location within the ceramic assembly below the primary RF power delivery electrode, the perimeter RF power delivery electrode having an annular shape defined by a top surface, a bottom surface, an inner edge, and an outer edge, the top and bottom surfaces of the perimeter RF power delivery electrode oriented substantially parallel to the primary RF power delivery electrode, the inner edge of the perimeter RF power delivery electrode positioned radially closer to a centerline of the ceramic assembly than an outer edge of the primary RF power delivery electrode, wherein the cen

Assignees

• Lam Res Corp

Inventors

• Benjamin Neil Martin Paul
• Povolny Henry
• Ricci Anthony J

Classifications

• H10P74/238

  comprising acting in response to an ongoing measurement without interruption of processing, e.g. endpoint detection or in-situ thickness measurement · CPC title

• H10P72/0604

  Process monitoring, e.g. flow or thickness monitoring · CPC title

• H10P72/722 Primary

  Details of electrostatic chucks · CPC title

• H01J37/32697

  Electrostatic control · CPC title

• H01J37/32091

  the radio frequency energy being capacitively coupled to the plasma · CPC title