US Patent Issued to SHIN-ETSU CHEMICAL on Feb. 17 for "Positive resist composition and pattern forming process" (Japanese Inventors)

ALEXANDRIA, Va., Feb. 17 -- United States Patent no. 12,554,197, issued on Feb. 17, was assigned to SHIN-ETSU CHEMICAL Co. LTD. (Tokyo).

"Positive resist composition and pattern forming process" was invented by Jun Hatakeyama (Joetsu, Japan), Shun Kikuchi (Joetsu, Japan) and Kousuke Ohyama (Joetsu, Japan).

According to the abstract* released by the U.S. Patent & Trademark Office: "A positive resist composition is provided comprising a base polymer end-capped with a salt consisting of an ammonium cation linked to a sulfide group and a fluorinated anion. Because of controlled acid diffusion, a resist film of the composition forms a pattern of good profile with a high resolution and reduced edge roughness or dimensional variation."

The pate...