Method and apparatus for diagnosing status of parts in real time in plasma processing equipment

Patent metadata

Field	Value
Publication number	US-9541514-B2
Application number	US-201514969614-A
Country	US
Kind code	B2
Filing date	Dec 15, 2015
Priority date	Sep 4, 2007
Publication date	Jan 10, 2017
Grant date	Jan 10, 2017

Abstract

Apparatus and methods for diagnosing status of a consumable part of a plasma reaction chamber, the consumable part including at least one conductive element embedded therein. The method includes the steps of: coupling the conductive element to a power supply so that a bias potential relative to the ground is applied to the conductive element; exposing the consumable part to plasma erosion until the conductive element draws a current from the plasma upon exposure of the conductive element to the plasma; measuring the current; and evaluating a degree of erosion of the consumable part due to the plasma based on the measured current.

First claim

What is claimed is:

1. A consumable part of a plasma reaction chamber, the consumable part comprising:
an electrode formed of electrically conductive material and including a surface to be exposed to plasma;
conductive elements embedded in the electrically conductive material of the electrode and entirely surrounded by and electrically insulated from the electrically conductive material of the electrode by a dielectric layer;
the electrode configured such that the conductive elements can be coupled to a probe circuit which can be coupled to a power supply and ground to apply a bias potential to the conductive elements relative to ground; and
the conductive elements are operative to draw a current from the plasma upon exposure of the conductive elements to the plasma and the conductive elements are electrically connected to each other by a conductive wire embedded in and electrically insulated from the electrically conductive material of the electrode.

2. The consumable part of claim 1 , wherein the power supply is a DC power source.

3. The consumable part of claim 1 , wherein the probe circuit includes a resistor and a voltmeter to measure an electrical potential across the resistor.

4. The consumable part of claim 1 , wherein each of the conductive elements has a shape selected from the group consisting of pin, polygonal, circular, and annular.

5. The consumable part of claim 1 , wherein the power supply is operable to supply a bias potential of 10 to 15 volts relative to the ground to the conductive elements.

6. The consumable part of claim 1 , wherein the power supply is connected in series to the probe circuit.

7. The consumable part of claim 3 , wherein the voltmeter is connected to the resistor in parallel.

8. The consumable part of claim 1 , wherein the conductive elements are embedded at a depth corresponding to a diagnostic event.

9. The consumable part of claim 8 , wherein the diagnostic event is an end of a useful lifetime of the consumable part.

10. The consumable part of claim 1 , wherein the conductive elements are annular conductive elements embedded in the consumable part.

11. A consumable part configured as a diagnostic sensor for monitoring the operational condition and structural status of an edge ring for use in a plasma reaction chamber, comprising:
an edge ring of dielectric material including a surface to be exposed to plasma when the edge ring is mounted in the plasma reaction chamber;
a plurality of probes of electrically conductive material completely surrounded by and
embedded in the edge ring and arranged circumferentially at a preset angular interval about a central axis of the edge ring, and
a connection wire embedded in the edge ring and electrically connected to each of the plurality of probes.

12. The consumable part of claim 11 , wherein the plurality of probes are coupled to a probe circuit.

13. A method for diagnosing operational conditions of an edge ring mounted in a plasma reaction chamber in real time, comprising:
processing a semiconductor substrate in the plasma reaction chamber using the plurality of probes in the consumable part of claim 12 ; and
monitoring signals from the plurality of probes simultaneously.

Assignees

• Lam Res Corp
• I Am Res Corp

Inventors

• Patrick Roger

Classifications

• Y10T29/49004

  including measuring or testing of device or component part · CPC title

• G01N17/04

  Corrosion probes · CPC title

• G01N27/20 Primary

  Investigating the presence of flaws · CPC title

• G01N17/00

  Investigating resistance of materials to the weather, to corrosion, or to light · CPC title

• C23C16/50

  using electric discharges {(generation and control of plasma in discharge tubes for surface treatment H01J37/32, H01J37/34)} · CPC title