Patent · US Expired

Indirect endpoint detection by chemical reaction

US6066564A · kind A · utility

7Cited by
21References
15Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 6, 1998
Grant dateMay 23, 2000
Priority date
Expiry dateMay 6, 2018

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01L21/31053
  • WIPO fieldMachine tools
  • WIPO sectorMechanical engineering

Abstract

Detection of the endpoint for removal of a target film overlying a stopping film by removing the target film with a process that selectively generates a chemical reaction product (for example ammonia when polishing a wafer with a nitride film in a slurry containing KOH) with one of the stopping film and the target film, converting the chemical reaction product to a separate product, and monitoring the level of the separate product as the target film is removed.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.