Method and apparatus for calibrating optical path degradation useful for decoupled plasma nitridation chambers

Patent metadata

Field	Value
Publication number	US-9865438-B2
Application number	US-201113188866-A
Country	US
Kind code	B2
Filing date	Jul 22, 2011
Priority date	Oct 8, 2008
Publication date	Jan 9, 2018
Grant date	Jan 9, 2018

Abstract

Methods for matching semiconductor processing chambers using a calibrated spectrometer are disclosed. In one embodiment, plasma attributes are measured for a process in a reference chamber and a process in an aged chamber. Using a calibrated light source, an optical path equivalent to an optical path in a reference chamber and an optical path in an aged chamber can be compared by determining a correction factor. The correction factor is applied to adjust a measured intensity of plasma radiation through the optical path in the aged chamber. Comparing a measured intensity of plasma radiation in the reference chamber and the adjusted measured intensity in the aged chamber provide an indication of changed chamber conditions. A magnitude of change between the two intensities can be used to adjust the process parameters to yield a processed substrate from the aged chamber which matches that of the reference chamber.

First claim

We claim:

1. A kit for adjusting an operational parameter setting in a substrate processing chamber, comprising:
a radiation source having a wavelength that is representative of a plasma spectrum generated in a chamber;
a calibrated radiation detector, calibrated to the radiation source;
a reference optical window having a known attenuation at the wavelength from the radiation source; and
an adjustment table to adjust the operational parameter of the substrate processing chamber based on a correction factor determined from a measured optical intensity of the radiation source through the reference optical window compared to a measured optical intensity of the radiation source through a used chamber window, where the operational parameter is modified in accordance with the correction factor.

2. The kit as claimed in claim 1 , further comprising a structure to fix a position of the radiation source, the reference optical window and the calibrated radiation detector.

3. The kit as claimed in claim 1 , wherein the adjustment table is implemented in a computing device.

4. The kit as claimed in claim 1 , wherein the wavelength of the radiation source is at a discrete wavelength that coincides with a spectrum peak in the plasma radiation.

5. The kit as claimed in claim 1 , wherein the radiation source is a single narrow band discrete radiation source.

6. The kit as claimed in claim 5 , which further comprises multiple discrete sources.

7. The kit as claimed in claim 1 , wherein the radiation source is a standardized broadband radiation source.

8. The kit as claimed in claim 1 , wherein the radiation source, reference optical window, and calibrated radiation detector form an optical path for measuring an optical intensity through the reference optical window.

Assignees

• Tallavarjula Sairaju
• Pradhan Kailash
• Nguyen Huy Q
• Li Jian
• Applied Materials Inc

Inventors

• Tallavarjula Sairaju
• Pradhan Kailash
• Nguyen Huy Q
• Li Jian

Classifications

• H01J37/32935

  Monitoring and controlling tubes by information coming from the object and/or discharge · CPC title

• G01N21/274

  Calibration, base line adjustment, drift correction · CPC title

• H01J37/32972 Primary

  Spectral analysis · CPC title

• G01N21/66

  electrically excited, e.g. electroluminescence · CPC title

• G01J3/443

  Emission spectrometry · CPC title