Spatially resolved optical emission spectroscopy (OES) in plasma processing

US9970818B2 · kind B2 · utility

Assignee

• TOKYO ELECTRON LIMITED · JP

Inventors

• Junwei Bao · Los Altos, US
• Ching-Ling Meng · Fremont, US
• Holger Tuitje · Fremont, US
• Mihail Mihaylov · San Jose, US
• Yan Chen · Cupertino, US
• Zheng Yan · Short Hills, US
• Haixing Zou · Sunnyvale, US
• Hanyou Chu · Palo Alto, US

Key dates

• Filing date: Oct 31, 2014
• Grant date: May 15, 2018
• Expiry date: Apr 17, 2035

Classification

• Technology area (CPC G): Physics
• CPC primary: G01N2201/10
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

Disclosed is a method, computer method, system, and apparatus for measuring two-dimensional distributions of optical emissions from a plasma in a semiconductor plasma processing chamber. The acquired two-dimensional distributions of plasma optical emissions can be used to infer the two-dimensional distributions of concentrations of certain chemical species of interest that are present in the plasma, and thus provide a useful tool for process development and also for new and improved processing tool development. The disclosed technique is computationally simple and inexpensive, and involves the use of an expansion of the assumed optical intensity distribution into a sum of basis functions that allow for circumferential variation of optical intensity. An example of suitable basis functions are Zernike polynomials.