INDIRECT ENDPOINT DETECTION BY CHEMICAL REACTION AND CHEMILUMINESCENCE

摘要

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 (312) (ammonia is a reaction product, 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 with the help of a converter (400), producing excited molecules from the separate product, detecting the level of light emitted from the flow of the excited molecules (402) passing through a chemiluminescence detector (404) and a very sensitive PMT (410) as the target film is removed.