US Patent Issued to Lam Research on Nov. 25 for "Symmetric coupling of coil to direct-drive radiofrequency power supplies" (California Inventors)

ALEXANDRIA, Va., Nov. 25 -- United States Patent no. 12,482,634, issued on Nov. 25, was assigned to Lam Research Corp. (Fremont, Calif.).

"Symmetric coupling of coil to direct-drive radiofrequency power supplies" was invented by John Drewery (San Jose, Calif.) and Alexander Miller Paterson (San Jose, Calif.).

According to the abstract* released by the U.S. Patent & Trademark Office: "A coil is disposed next to a plasma processing chamber. A first direct-drive radiofrequency (RF) power supply has an output through which a first shaped-amplified square waveform signal is transmitted. A first reactive circuit is connected between the output of the first direct-drive RF power supply and a first end of the coil. The first reactive circuit tran...