Bath systems and methods thereof

Patent metadata

Field	Value
Publication number	US-12226796-B2
Application number	US-202318351245-A
Country	US
Kind code	B2
Filing date	Jul 12, 2023
Priority date	Jun 7, 2021
Publication date	Feb 18, 2025
Grant date	Feb 18, 2025

Abstract

A method of processing a plurality of substrates includes immersing the plurality of substrates into a bath solution contained in a bath chamber; generating gas bubbles in the bath solution; projecting light from a light source toward the bath chamber; generating light sensor data by capturing light emanating off the bath chamber after interacting with the gas bubbles with a light sensor; and converting the light sensor data into a metric for the bath solution.

First claim

What is claimed is:

1. A bath processing tool comprising:
a bath chamber for wet processing wafers;
an electromagnetic radiation sensor to capture an electromagnetic signal from a bath solution in the bath chamber, wherein the electromagnetic radiation sensor comprises a long wavelength infrared camera;
a processor; and
a non-transitory memory storing a program and coupled to the processor, the program to be executed in the processor and comprising instructions to:
determine a metric of the bath solution based on the electromagnetic signal, and
identify that a target specification for processing the wafers is reached based on the metric of the bath solution, wherein the metric is an endpoint metric, and wherein the instructions to determine the endpoint metric of the bath solution comprise further instructions to: determine a temperature of the bath solution with the long wavelength infrared camera.

2. The bath processing tool of claim 1 , wherein the processor is configured to terminate the process for wet processing the wafers.

3. The bath processing tool of claim 1 , wherein the metric is a process target specification and the processor is configured to make adjustments to a gas flow, make adjustments to a power to a heating element, or make adjustments to a flow of a bath solution component to keep a bath at the process target specification.

4. A bath processing tool comprising:
a bath chamber for wet processing wafers;
an electromagnetic radiation source configured to generate an electromagnetic signal, the electromagnetic radiation source comprising multiple electromagnetic radiation sources, each of the multiple electromagnetic radiation sources having a different short infrared wavelength configured to project the short infrared wavelengths through a bath solution in the bath chamber;
an electromagnetic radiation sensor to capture the electromagnetic signal from the bath solution in the bath chamber, wherein the electromagnetic radiation sensor is configured to capture the short infrared wavelengths transmitted through the bath solution;
a processor; and
a non-transitory memory storing a program and coupled to the processor, the program to be executed in the processor and comprising instructions to:
determine an endpoint metric of the bath solution based on the electromagnetic signal, the endpoint metric of the bath solution comprises a spectrum of a component in the bath solution, and
identify that a target specification for processing the wafers is reached based on the endpoint metric of the bath solution.

5. A bath processing tool comprising:
a bath chamber for wet processing wafers;
a plurality of light sources configured to generate an electromagnetic signal;
an electromagnetic radiation sensor to capture the electromagnetic signal from a bath solution in the bath chamber;
a processor; and
a non-transitory memory storing a program and coupled to the processor, the program to be executed in the processor and comprising instructions to:
determine a metric of the bath solution based on the electromagnetic signal, and
identify that a target specification for processing the wafers is reached based on the metric of the bath solution, wherein the instructions to determine the metric of the bath solution comprises instructions to
generate gas bubbles in the bath solution while immersing the wafers into the bath solution contained in the bath chamber;
project light from the plurality of light sources toward the bath chamber, each of the wafers extending across multiple zones that are being illuminated with more than one of the plurality of light sources;
generate light sensor data by capturing light emanating off the bath chamber after interacting with the gas bubbles with the electromagnetic radiation sensor; and
generate across-wafer zone comparison data based on comparing light emanating off from one of the multiple zones with light emanating off from another one of the multiple zones.

6. The bath processing tool of claim 1 , wherein the metric for the bath solution comprises a static bubble size and count density, a dynamic bubble size and count density, a static bubble uniformity, a dynamic bubble uniformity, a bath solution uniformity, or a bubble generation rate.

7. The bath processing tool of claim 4 , wherein the electromagnetic radiation sensor comprises a short wavelength camera with a tunable wavelength filter, wherein the instructions to determine the endpoint metric of the bath solution comprise further instructions to: determine the spectrum of the component in the bath solution with the short wavelength camera with the tunable wavelength filter.

8. The bath processing tool of claim 5 , wherein the metric is a process target specification and the processor is configured to make adjustments to a gas flow, make adjustments to a power to a heating element.

9. The bath processing tool of claim 5 , wherein the metric is a process target specification and the processor is configured to make adjustments to a flow of a bath solution component to keep a bath at the process target specification.

10. The bath processing tool of claim 5 , wherein the electromagnetic radiation sensor comprises a long wavelength infrared camera, a visible light camera, or a short wavelength camera.

11. The bath processing tool of claim 5 , wherein the instructions to generate the gas bubbles comprises instructions to inject the gas bubbles through a gas injector or boil the bath solution.

12. The bath processing tool of claim 5 , wherein the metric for the bath solution comprises a static bubble size and count density, a dynamic bubble size and count density, a static bubble uniformity, a dynamic bubble uniformity, a bath solution uniformity, or a bubble generation rate.

13. The bath processing tool of claim 5 , wherein the instructions to project the light from the plurality of light sources toward the bath chamber comprises instructions to illuminate the multiple zones of the bath solution with multiple light sources spaced across an outer dimension of the bath chamber.

14. The bath processing tool of claim 13 , wherein the instructions to generate light sensor data by capturing light emanating off the gas bubbles comprises instructions to
capture light emanating from a first zone of the multiple zones with a first light sensor of the light sensor; and
capture light emanating from a second zone of the multiple zones with a second light sensor of the light sensor; and
wherein the instructions to generate across-wafer zone comparison data comprises instructions to compare a bubble property in the first zone with a bubble property in the second zone based on the light sensor data.

15. The bath processing tool of claim 14 , wherein the outer dimension of the bath chamber is perpendicular to a major surface of the wafers, wherein the first zone includes a first portion of a gas injector with a first orifice, and wherein the second zone includes a second portion of the gas injector with a second orifice.

16. The bath processing tool of claim 14 , wherein the multiple light sources comprise lights configured to periodically turn on and off at a duty cycle, and wherein the instructions to illuminate the multiple zones comprises instructions to flash the first zone at a first frequency synchronous with the first light sensor and flash the second zone at a second frequency synchronous with the second light sensor.

17. The bath processing tool of claim 5 , wherein the instructions to project the light from the plurality of light sources towards the bath chamber compri

Assignees

• Tokyo Electron Ltd

Inventors

• Carcasi Michael
• Simms Ihsan
• Estrella Joel
• Rotondaro Antonio Luis Pacheco
• Hooge Joshua
• Marumoto Hiroshi

Classifications

• H10P70/23

  during, before or after processing of insulating materials · CPC title

• H10P50/283

  by chemical means · CPC title

• H10P72/0604 Primary

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

• H10P72/0426

  with the semiconductor substrates being dipped in baths or vessels · CPC title

• B08B3/106

  by boiling the liquid · CPC title