Spatial optical emission spectroscopy for etch uniformity

Patent metadata

Field	Value
Publication number	US-12405164-B2
Application number	US-202318138914-A
Country	US
Kind code	B2
Filing date	Apr 25, 2023
Priority date	Apr 20, 2021
Publication date	Sep 2, 2025
Grant date	Sep 2, 2025

Abstract

An apparatus includes a base component and a plurality of collimators housed within the base component. Each collimator of the plurality of collimators corresponds to a respective location of a plurality of locations of a wafer in an etch chamber. The plurality of locations includes a center location of the wafer, a plurality of inner ring locations along an inner ring of the wafer associated with a first set of radially symmetric optical emission spectroscopy (OES) signal sampling paths, and a plurality of outer ring locations along an outer ring of the wafer associated with a second set of radially symmetric OES signal sampling paths.

First claim

What is claimed is:

1. An apparatus comprising:
a base component; and
a plurality of collimators housed within the base component, each collimator of the plurality of collimators corresponding to a respective location of a plurality of locations of a wafer in an etch chamber, wherein the plurality of locations comprises a center location of the wafer, a plurality of inner ring locations along an inner ring of the wafer associated with a first set of radially symmetric optical emission spectroscopy (OES) signal sampling paths, and a plurality of outer ring locations along an outer ring of the wafer associated with a second set of radially symmetric OES signal sampling paths.

2. The apparatus of claim 1 , further comprising a guide, operatively coupled to the plurality of collimators, to guide each OES signal of the plurality of OES signals along a respective spatial OES signal sampling path.

3. The apparatus of claim 1 , wherein each collimator of the plurality of collimators corresponds to a respective collection cylinder of a plurality of collection cylinders, and wherein each collection cylinder of the plurality of collection cylinders is to collect a respective OES signal of a plurality of OES signals.

4. The apparatus of claim 1 , wherein the inner ring comprises 3 inner ring locations and the outer ring comprises 3 outer ring locations, and the plurality of collimators comprises 7 collimators.

5. The apparatus of claim 1 , wherein the base component further comprises:
an upper clamp for securing a set of optical channels, wherein each collimator of the plurality of collimators is attached to a respective end of an optical channel of the set;
a base; and
a plurality of ports formed within the base, wherein each collimator of the plurality of collimators is inserted into a respective port of the plurality of ports.

6. A system comprising:
a memory; and
a processing device, operatively coupled to the memory, to perform operations comprising:
initiating an iteration of an etch process to etch a wafer using an etch recipe;
receiving, from an optical detector, a spatial optical emission spectroscopy (OES) analysis of a plurality of OES signals, wherein each OES signal of the plurality of OES signals corresponds to a respective location of a plurality of locations of the wafer, and wherein the plurality of locations comprises a center location of the wafer, a plurality of inner ring locations along an inner ring of the wafer associated with a first set of radially symmetric OES signal sampling paths, and a plurality of outer ring locations along an outer ring of the wafer associated with a second set of radially symmetric OES signal sampling paths; and
performing one or more actions related to etch uniformity based on the spatial OES analysis.

7. The system of claim 6 , further comprising a plurality of collimators housed within a base component.

8. The system of claim 7 , further comprising a guide, operatively coupled to the plurality of collimators, to guide each OES signal of the plurality of OES signals along a respective spatial OES signal sampling path.

9. The system of claim 7 , wherein each collimator of the plurality of collimators corresponds to a respective collection cylinder of a plurality of collection cylinders, and wherein each collection cylinder of the plurality of collection cylinders is to collect a respective OES signal of the plurality of OES signals.

10. The system of claim 7 , wherein the base component further comprises:
an upper clamp for securing a set of optical channels, wherein each collimator of the plurality of collimators is attached to a respective end of an optical channel of the set;
a base; and
a plurality of ports formed within the base, wherein each collimator of the plurality of collimators is inserted into a respective port of the plurality of ports.

11. The system of claim 6 , wherein the processing device is operatively coupled to a switch device to enable the plurality of OES signals to be selectively analyzed with the optical detector.

12. The system of claim 6 , wherein the spatial OES analysis determines etch rates with respect to each of the locations.

13. The system of claim 6 , wherein performing the one or more actions comprises optimizing etch uniformity.

14. The system of claim 6 , wherein performing the one or more actions comprises monitoring etch uniformity.

15. The system of claim 6 , wherein performing the one or more actions comprises controlling etch uniformity.

16. The system of claim 6 , wherein the plurality of inner ring locations comprises 3 inner ring locations and the plurality of outer ring locations comprises 3 outer ring locations.

17. A method comprising:
initiating, by a processing device, an iteration of an etch process to etch a wafer using an etch recipe;
receiving, by the processing device from an optical detector, a spatial optical emission spectroscopy (OES) analysis of a plurality of OES signals, wherein each OES signal of the plurality of OES signals corresponds to a respective location of a plurality of locations of the wafer, and wherein the plurality of locations comprises a center location of the wafer, a plurality of inner ring locations along an inner ring of the wafer associated with a first set of radially symmetric OES signal sampling paths, and a plurality of outer ring locations along an outer ring of the wafer associated with a second set of radially symmetric OES signal sampling paths; and
performing, by the processing device, one or more actions related to etch uniformity based on the spatial OES analysis.

18. The method of claim 17 , wherein the analysis of the plurality of OES signals determines etch rates with respect to each of the locations.

19. The method of claim 17 , wherein performing the one or more actions comprises performing at least one of: optimizing etch uniformity, monitoring the etch uniformity, or controlling the etch uniformity.

20. The method of claim 17 , wherein the plurality of inner ring locations comprises 3 inner ring locations and the plurality of outer ring locations comprises 3 outer ring locations.

Assignees

• Applied Materials Inc

Inventors

• Erickson Blake
• Berding Keith
• Kutney Michael
• Zhu Zhaozhao
• Wu Tsung Feng
• Willwerth Michael D
• Ludwig Jeffrey

Classifications

• G01N2021/8416

  and process controlling, not otherwise provided for · CPC title

• G01N21/211

  Ellipsometry (optical thickness measurement G01B11/06) · CPC title

• G01J3/443

  Emission spectrometry · CPC title

• G01N21/9501

  Semiconductor wafers (manufacturing processes per se of semiconductor devices implementing a measuring step H10P74/20) · CPC title

• G01N21/68 Primary

  using high frequency electric fields · CPC title