US Patent Issued to Tokyo Electron on Feb. 24 for "Monitoring method and plasma processing apparatus" (Japanese Inventors)

ALEXANDRIA, Va., Feb. 24 -- United States Patent no. 12,562,345, issued on Feb. 24, was assigned to Tokyo Electron Ltd. (Tokyo).

"Monitoring method and plasma processing apparatus" was invented by Takeshi Kobayashi (Iwate, Japan), Jun Sato (Iwate, Japan) and Takashi Chiba (Iwate, Japan).

According to the abstract* released by the U.S. Patent & Trademark Office: "A monitoring method includes steps of (a) placing a substrate on a mounting stage of a processing chamber of a plasma processing apparatus; (b) supplying a pulsed wave of RF power with a predetermined duty ratio from an RF power supply connected to an antenna; and (c) monitoring a plasma state based on a converted value of a Vpp voltage of an output terminal of a matching unit arr...