ALEXANDRIA, Va., Dec. 2 -- United States Patent no. 12,488,990, issued on Dec. 2, was assigned to Tokyo Electron Ltd. (Tokyo).
"Etching method and plasma processing apparatus" was invented by Fumiya Takata (Miyagi, Japan), Shota Yoshimura (Miyagi, Japan), Shinya Morikita (Miyagi, Japan) and Kota Oikawa (Miyagi, Japan).
According to the abstract* released by the U.S. Patent & Trademark Office: "An etching method includes: (a) providing a substrate including a first region containing silicon and nitrogen and a second region containing silicon and oxygen; (b) forming a tungsten-containing deposit on the first region using a first plasma generated from a first processing gas containing fluorine, tungsten, and at least one selected from a grou...